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Mondragón-Herrera LI, Vargas-Coronado RF, Carrillo-Escalante H, Cauich-Rodríguez JV, Hernández-Sánchez F, Velasco-Santos C, Avilés F. Mechanical, Thermal, and Physicochemical Properties of Filaments of Poly (Lactic Acid), Polyhydroxyalkanoates and Their Blend for Additive Manufacturing. Polymers (Basel) 2024; 16:1062. [PMID: 38674981 PMCID: PMC11053644 DOI: 10.3390/polym16081062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2024] [Revised: 04/05/2024] [Accepted: 04/07/2024] [Indexed: 04/28/2024] Open
Abstract
Polymeric blends are employed in the production of filaments for additive manufacturing to balance mechanical and processability properties. The mechanical and thermal properties of polymeric filaments made of poly (lactic acid) (PLA), polyhydroxyalkanoates (PHA), and its blend (PLA-PHA) are investigated herein and correlated to their measured structural and physicochemical properties. PLA exhibits the highest stiffness and tensile strength, but lower toughness. The mechanical properties of the PLA-PHA blend were similar to those of PLA, but with a significantly higher toughness. Despite the lower mechanical properties of neat PHA, incorporating a small amount (12 wt.%) of PHA into PLA significantly enhances toughness (approximately 50%) compared to pure PLA. The synergistic effect is attributed to the spherulitic morphology of blended PHA in PLA, promoting interactions between the amorphous regions of both polymers. Thermal stability is notably improved in the PLA-PHA blend, as determined by thermogravimetric analysis. The blend also exhibits lower cold crystallization and glass transition temperatures as compared to PLA, which is beneficial for additive manufacturing. Following additive manufacturing, X-ray photoelectron spectroscopic showed that the three filaments present an increase in C-C and C=O bonds associated with the loss of C-O bonds. The thermal process induces a slight increase in crystallinity in PHA due to chain reorganization. The study provides insights into the thermal and structural changes occurring during the melting process of additive manufacturing.
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Affiliation(s)
- L. Itzkuautli Mondragón-Herrera
- Centro de Investigación Científica de Yucatán, A. C., Materials Department, Calle 43 No. 130 x 32 y 34, Col. Chuburná de Hidalgo, Mérida 97205, Yucatán, Mexico; (L.I.M.-H.); (R.F.V.-C.); (F.H.-S.)
| | - R. F. Vargas-Coronado
- Centro de Investigación Científica de Yucatán, A. C., Materials Department, Calle 43 No. 130 x 32 y 34, Col. Chuburná de Hidalgo, Mérida 97205, Yucatán, Mexico; (L.I.M.-H.); (R.F.V.-C.); (F.H.-S.)
| | - H. Carrillo-Escalante
- Centro de Investigación Científica de Yucatán, A. C., Materials Department, Calle 43 No. 130 x 32 y 34, Col. Chuburná de Hidalgo, Mérida 97205, Yucatán, Mexico; (L.I.M.-H.); (R.F.V.-C.); (F.H.-S.)
| | - J. V. Cauich-Rodríguez
- Centro de Investigación Científica de Yucatán, A. C., Materials Department, Calle 43 No. 130 x 32 y 34, Col. Chuburná de Hidalgo, Mérida 97205, Yucatán, Mexico; (L.I.M.-H.); (R.F.V.-C.); (F.H.-S.)
| | - F. Hernández-Sánchez
- Centro de Investigación Científica de Yucatán, A. C., Materials Department, Calle 43 No. 130 x 32 y 34, Col. Chuburná de Hidalgo, Mérida 97205, Yucatán, Mexico; (L.I.M.-H.); (R.F.V.-C.); (F.H.-S.)
| | - C. Velasco-Santos
- División de Estudios de Posgrado e Investigación, Tecnológico Nacional de México Campus Querétaro, Av. Tecnológico s/n, esq. Gral. Mariano Escobedo, Col. Centro Histórico, Santiago de Querétaro 76000, Querétaro, Mexico;
| | - F. Avilés
- Centro de Investigación Científica de Yucatán, A. C., Materials Department, Calle 43 No. 130 x 32 y 34, Col. Chuburná de Hidalgo, Mérida 97205, Yucatán, Mexico; (L.I.M.-H.); (R.F.V.-C.); (F.H.-S.)
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Ftiti S, Cifuentes SC, Guidara A, Rams J, Tounsi H, Fernández-Blázquez JP. The Structural, Thermal and Morphological Characterization of Polylactic Acid/Β-Tricalcium Phosphate (PLA/Β-TCP) Composites upon Immersion in SBF: A Comprehensive Analysis. Polymers (Basel) 2024; 16:719. [PMID: 38475402 DOI: 10.3390/polym16050719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Revised: 02/27/2024] [Accepted: 02/29/2024] [Indexed: 03/14/2024] Open
Abstract
Biocomposite films based on PLA reinforced with different β-TCP contents (10%, 20%, and 25%wt.) were fabricated via solvent casting and immersed in SBF for 7, 14, and 21 days. The bioactivity, morphological, and thermal behavior of composites with immersion were studied using scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) microanalysis, weight loss (WL), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and gel permeation chromatography (GPC). This broad analysis leads to a deeper understanding of the evolution of the polymer-filler interaction with the degradation of the biocomposites. The results showed that β-TCP gradually evolved into carbonated hydroxyapatite as the immersion time increased. This evolution affected the interaction of β-TCP with PLA. PLA and β-TCP interactions differed from PLA and carbonated hydroxyapatite interactions. It was observed that β-TCP inhibited PLA hydrolysis but accelerated the thermal degradation of the polymer. β-TCP retarded the cold crystallization of PLA and hindered its crystallinity. However, after immersion in SBF, particles accelerated the cold crystallization of PLA. Therefore, considering the evolution of β-TCP with immersion in SBF is crucial for an accurate analysis of the biocomposites' degradation. These findings enhance the comprehension of the degradation mechanism in PLA/β-TCP, which is valuable for predicting the degradation performance of PLA/β-TCP in medical applications.
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Affiliation(s)
- Sondes Ftiti
- Laboratory of Advanced Materials (LR01ES26), National Engineering School of Sfax, University of Sfax, Sfax 3038, Tunisia
| | - Sandra C Cifuentes
- Department of Applied Mathematics, Materials Science and Engineering and Electronic Technology, Universidad Rey Juan Carlos (URJC), 28933 Móstoles, Spain
| | - Awatef Guidara
- Laboratory of Advanced Materials (LR01ES26), National Engineering School of Sfax, University of Sfax, Sfax 3038, Tunisia
| | - Joaquín Rams
- Department of Applied Mathematics, Materials Science and Engineering and Electronic Technology, Universidad Rey Juan Carlos (URJC), 28933 Móstoles, Spain
| | - Hassib Tounsi
- Laboratory of Advanced Materials (LR01ES26), National Engineering School of Sfax, University of Sfax, Sfax 3038, Tunisia
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Zarei Chamgordani N, Asiaei S, Ghorbani-Bidkorpeh F, Babaee Foroutan M, Mahboubi A, Moghimi HR. Fabrication of controlled-release silver nanoparticle polylactic acid microneedles with long-lasting antibacterial activity using a micro-molding solvent-casting technique. Drug Deliv Transl Res 2024; 14:386-399. [PMID: 37578649 DOI: 10.1007/s13346-023-01406-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/22/2023] [Indexed: 08/15/2023]
Abstract
Most topical drug delivery techniques do not provide therapeutic concentrations for treatment of surgical site and other local infections and, therefore, require some kind of enhancement, such as physical methods like microneedles, the subject of the present investigation. Here, controlled-release long-lasting antibacterial polylactic acid (PLA) microneedles containing 1, 3, and 5% silver nanoparticles (AgNP) were prepared using micro-molding solvent-casting technique. Microneedles were characterized using optical microscopy, SEM, FTIR, XRD, and DSC. Also, mechanical strength, barrier disruption ability, insertion depth, in-vitro release kinetics, antibacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa, and silver permeation through rat skin were studied. Microneedles showed good mechanical strength with no signs of failure at an optimum PLA concentration of 25% (w/v). FTIR revealed no chemical interaction between ingredients, and XRD confirmed presence of AgNP in microneedles. Microneedles penetrated the skin model at depth of up to 1143 μm resulting 5-7 times increase in transepidermal water loss (TEWL). Release studies showed 2.2, 6.8, and 8.1 µg silver release from the whole body (obeying Higuchi's release model) and 0.33, 0.45, and 0.78 µg from the needles alone (obeying Fickian-cylindrical type release) for 1, 3, and 5% AgNP microneedles, respectively. Also, prolonged antibacterial activity (for 34 days) was observed. Skin studies over 72 h indicated that besides needles, silver is also released from the baseplate which had a marginal share in total silver permeation through the skin. In conclusion, a straightforward solvent-casting technique can be used to successfully prepare strong AgNP-containing PLA microneedles capable of long-lasting antibacterial activity.
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Affiliation(s)
- Nasrin Zarei Chamgordani
- Department of Pharmaceutics and Pharmaceutical Nanotechnology, School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Sasan Asiaei
- Sensors and Integrated Bio-MEMS/Microfluidics Laboratory, School of Mechanical Engineering, Iran University of Science and Technology, Tehran, Iran
| | - Fatemeh Ghorbani-Bidkorpeh
- Department of Pharmaceutics and Pharmaceutical Nanotechnology, School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | | | - Arash Mahboubi
- Department of Pharmaceutics and Pharmaceutical Nanotechnology, School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- Food Safety Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Hamid Reza Moghimi
- Department of Pharmaceutics and Pharmaceutical Nanotechnology, School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
- Protein Technology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
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Sadat-Shojai M, Kalantari-Lalari M, Asadnia M. New Three-Dimensional Bioactive Reinforcing Filler for Improving the Properties of Biomedical Polymers: Synthesis and Application. ACS OMEGA 2024; 9:2192-2203. [PMID: 38250428 PMCID: PMC10795145 DOI: 10.1021/acsomega.3c05373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 12/15/2023] [Accepted: 12/22/2023] [Indexed: 01/23/2024]
Abstract
In general, the efficiency of reinforcement for filler-based composites is greatly influenced by the filler properties. While much research has been conducted on filler percentage and filler-matrix bonding quality, there is not much research directed to the effect of filler geometry. Therefore, the aim of this article is to examine how a three-dimensional (3D) bioactive filler influences the strength enhancement of biomedical polymers. This was accomplished by first synthesizing highly regular dandelion-like hydroxyapatite (DHA) as a 3D bioactive filler using an optimized hydrothermal method, followed by surface modification with silane molecules. Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) was then used as a biomedical polymer model to fabricate solution-casted composites by using the as-synthesized DHA particles. The results showed that the composites loaded with the surface-modified DHA particles had significantly higher tensile strength and elastic modulus compared to the neat PHBV and composites having irregular particles. In addition to the mechanical properties, our research found that the 3D DHA filler had a significant impact on the biological characteristics of the PHBV, such as water wettability, biodegradability, bioactivity, and in vitro cell response. These findings suggested that particle geometry can play a more significant role in affecting the biological and mechanical performance of biomedical polymers than previously thought.
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Affiliation(s)
- Mehdi Sadat-Shojai
- Department of Chemistry, College of
Sciences, Shiraz University, Shiraz 71454, Iran
| | | | - Milad Asadnia
- Department of Chemistry, College of
Sciences, Shiraz University, Shiraz 71454, Iran
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Alexeeva OV, Olkhov AA, Konstantinova ML, Podmasterev VV, Petrova TV, Martirosyan LY, Karyagina OK, Kozlov SS, Lomakin SM, Tretyakov IV, Siracusa V, Iordanskii AL. A Novel Approach for Glycero-(9,10-trioxolane)-Trialeate Incorporation into Poly(lactic acid)/Poly(ɛ-caprolactone) Blends for Biomedicine and Packaging. Polymers (Basel) 2023; 16:128. [PMID: 38201793 PMCID: PMC10780447 DOI: 10.3390/polym16010128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 12/26/2023] [Accepted: 12/29/2023] [Indexed: 01/12/2024] Open
Abstract
The product of ozonolysis, glycero-(9,10-trioxolane)-trioleate (ozonide of oleic acid triglyceride, [OTOA]), was incorporated into polylactic acid/polycaprolactone (PLA/PCL) blend films in the amount of 1, 5, 10, 20, 30 and 40% w/w. The morphological, mechanical, thermal and antibacterial properties of the biodegradable PLA/PCL films after the OTOA addition were studied. According to DSC and XRD data, the degree of crystallinity of the PLA/PCL + OTOA films showed a general decreasing trend with an increase in OTOA content. Thus, a significant decrease from 34.0% for the reference PLA/PCL film to 15.7% for the PLA/PCL + 40% OTOA film was established using DSC. Observed results could be explained by the plasticizing effect of OTOA. On the other hand, the PLA/PCL film with 20% OTOA does not follow this trend, showing an increase in crystallinity both via DSC (20.3%) and XRD (34.6%). OTOA molecules, acting as a plasticizer, reduce the entropic barrier for nuclei formation, leading to large number of PLA spherulites in the plasticized PLA/PCL matrix. In addition, OTOA molecules could decrease the local melt viscosity at the vicinity of the growing lamellae, leading to faster crystal growth. Morphological analysis showed that the structure of the films with an OTOA concentration above 20% drastically changed. Specifically, an interface between the PLA/PCL matrix and OTOA was formed, thereby forming a capsule with the embedded antibacterial agent. The moisture permeability of the resulting PLA/PCL + OTOA films decreased due to the formation of uniformly distributed hydrophobic amorphous zones that prevented water penetration. This architecture affects the tensile characteristics of the films: strength decreases to 5.6 MPa, elastic modulus E by 40%. The behavior of film elasticity is associated with the redistribution of amorphous regions in the matrix. Additionally, PLA/PCL + OTOA films with 20, 30 and 40% of OTOA showed good antibacterial properties on Pseudomonas aeruginosa, Raoultella terrigena (Klebsiella terrigena) and Agrobacterium tumefaciens, making the developed films potentially promising materials for wound-dressing applications.
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Affiliation(s)
- Olga V. Alexeeva
- Emanuel Institute of Biochemical Physics of Russian Academy of Sciences, 119334 Moscow, Russia; (A.A.O.); (M.L.K.); (V.V.P.); (L.Y.M.); (O.K.K.); (S.S.K.); (S.M.L.)
| | - Anatoliy A. Olkhov
- Emanuel Institute of Biochemical Physics of Russian Academy of Sciences, 119334 Moscow, Russia; (A.A.O.); (M.L.K.); (V.V.P.); (L.Y.M.); (O.K.K.); (S.S.K.); (S.M.L.)
- N.N. Semenov Federal Research Center for Chemical Physics Russian Academy of Sciences, 119991 Moscow, Russia; (T.V.P.); (I.V.T.); (A.L.I.)
- Academic Department of Innovational Materials and Technologies Chemistry, Plekhanov Russian University of Economics, 117997 Moscow, Russia
| | - Marina L. Konstantinova
- Emanuel Institute of Biochemical Physics of Russian Academy of Sciences, 119334 Moscow, Russia; (A.A.O.); (M.L.K.); (V.V.P.); (L.Y.M.); (O.K.K.); (S.S.K.); (S.M.L.)
| | - Vyacheslav V. Podmasterev
- Emanuel Institute of Biochemical Physics of Russian Academy of Sciences, 119334 Moscow, Russia; (A.A.O.); (M.L.K.); (V.V.P.); (L.Y.M.); (O.K.K.); (S.S.K.); (S.M.L.)
| | - Tuyara V. Petrova
- N.N. Semenov Federal Research Center for Chemical Physics Russian Academy of Sciences, 119991 Moscow, Russia; (T.V.P.); (I.V.T.); (A.L.I.)
| | - Levon Yu. Martirosyan
- Emanuel Institute of Biochemical Physics of Russian Academy of Sciences, 119334 Moscow, Russia; (A.A.O.); (M.L.K.); (V.V.P.); (L.Y.M.); (O.K.K.); (S.S.K.); (S.M.L.)
| | - Olga K. Karyagina
- Emanuel Institute of Biochemical Physics of Russian Academy of Sciences, 119334 Moscow, Russia; (A.A.O.); (M.L.K.); (V.V.P.); (L.Y.M.); (O.K.K.); (S.S.K.); (S.M.L.)
| | - Sergey S. Kozlov
- Emanuel Institute of Biochemical Physics of Russian Academy of Sciences, 119334 Moscow, Russia; (A.A.O.); (M.L.K.); (V.V.P.); (L.Y.M.); (O.K.K.); (S.S.K.); (S.M.L.)
| | - Sergey M. Lomakin
- Emanuel Institute of Biochemical Physics of Russian Academy of Sciences, 119334 Moscow, Russia; (A.A.O.); (M.L.K.); (V.V.P.); (L.Y.M.); (O.K.K.); (S.S.K.); (S.M.L.)
- N.N. Semenov Federal Research Center for Chemical Physics Russian Academy of Sciences, 119991 Moscow, Russia; (T.V.P.); (I.V.T.); (A.L.I.)
| | - Ilya V. Tretyakov
- N.N. Semenov Federal Research Center for Chemical Physics Russian Academy of Sciences, 119991 Moscow, Russia; (T.V.P.); (I.V.T.); (A.L.I.)
| | - Valentina Siracusa
- Department of Chemical Science (DSC), University of Catania, Viale A. Doria 6, 95125 Catania, Italy
| | - Alexey L. Iordanskii
- N.N. Semenov Federal Research Center for Chemical Physics Russian Academy of Sciences, 119991 Moscow, Russia; (T.V.P.); (I.V.T.); (A.L.I.)
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Laraba SR, Rezzoug A, Avcu E, Luo W, Halimi R, Wei J, Li Y. Enhancing the tribological performance of PLA-based biocomposites reinforced with graphene oxide. J Mech Behav Biomed Mater 2023; 148:106224. [PMID: 37944226 DOI: 10.1016/j.jmbbm.2023.106224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 10/31/2023] [Accepted: 11/03/2023] [Indexed: 11/12/2023]
Abstract
Poly(lactic acid) (PLA) reinforced with graphene has gained substantial interest as a biomaterial, where the tribological and mechanical behavior of PLA/graphene composites are major concerns. This study aims to develop PLA-based biocomposites reinforced with graphene oxide (GO) that have enhanced tribological capabilities. First, homogenous dispersions of GO and GO treated with the anionic surfactant dioctyl sulfosuccinate sodium salt (AOT) were retained. Then, poly(L-lactic acid) (PLLA) biopolymer and PLLA/GO, PLLA/GO(AOT), PLA/GO(AOT), and PLLA/polyethylene glycol (PEG)/GO biocomposite samples were produced via hot pressing, and their tribological behavior was examined in detail. The worn surface characteristics were examined using scanning electron microscopy (SEM), 3D confocal microscopy, and atomic force microscopy (AFM). Results showed that GO reinforcement considerably affected the sliding wear behavior of PLA. Contrary to anticipated, surface treatment of GO does not improve the PLLA/GO wear resistance; rather, it increases the wear rate. PEG positively affects the sliding wear performance of PLLA/GO. PLLA/GO and PLLA/PEG/GO biocomposites exhibited the lowest wear rate at normal loads of 5 and 8 N, respectively, which was decreased by about 50% compared to unreinforced PLLA samples. With the addition of GO, the wear mechanisms of the PLA-based biocomposites changed from adhesive wear to abrasive wear. These findings might increase the applicability of PLA-based biocomposites where tribological performance is the main concern, such as biodegradable implants for load-bearing bone fractures or scaffolds, opening up new opportunities for their use.
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Affiliation(s)
- Selsabil Rokia Laraba
- Key Laboratory for Ultrafine Materials of Ministry of Education, East China University of Science and Technology, Shanghai, 200237, PR China.
| | - Amine Rezzoug
- Research Center in Industrial Technologies (CRTI), P.O.Box 64, Cheraga, 16014, Algiers, Algeria
| | - Egemen Avcu
- Department of Mechanical Engineering, Kocaeli University, Kocaeli, 41001, Turkey; Ford Otosan Ihsaniye Automotive Vocational School, Kocaeli University, Kocaeli, 41650, Turkey
| | - Wei Luo
- Key Laboratory for Ultrafine Materials of Ministry of Education, East China University of Science and Technology, Shanghai, 200237, PR China
| | - Rafik Halimi
- Research Center in Industrial Technologies (CRTI), P.O.Box 64, Cheraga, 16014, Algiers, Algeria
| | - Jie Wei
- Key Laboratory for Ultrafine Materials of Ministry of Education, East China University of Science and Technology, Shanghai, 200237, PR China.
| | - Yulin Li
- Key Laboratory for Ultrafine Materials of Ministry of Education, East China University of Science and Technology, Shanghai, 200237, PR China.
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Magee E, Tang F, Walker M, Zak A, Tenne R, McNally T. Silane functionalization of WS 2 nanotubes for interaction with poly(lactic acid). NANOSCALE 2023; 15:7577-7590. [PMID: 37039126 DOI: 10.1039/d3nr00583f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Functionalisation of nanofillers is required for the promotion of strong interfacial interactions with polymers and is essential as a route for the preparation of (nano)composites with superior mechanical properties. Tungsten disulphide nanotubes (WS2 NTs) were functionalized using (3-aminopropyl) triethoxysilane (APTES) for preparation of composites with poly(lactic acid) (PLA). The WS2 NTs : APTES ratios used were 1 : 1, 1 : 2 and 1 : 4 WS2 NTs : APTES. The APTES formed siloxane networks bound to the NTs via surface oxygen and carbon moieties adsorbed on the WS2 NTs surface, detected by X-ray photoelectron spectroscopy (XPS) studies and chemical mapping using energy dispersive X-ray spectroscopy in the scanning transmission electron microscope (STEM-EDS). The successful silane modification of the WS2 NTs was clearly evident with both significant peak shifting by as much as 60 cm-1 for Si-O-Si vibrations (FTIR) and peak broadening of the A1g band in the Raman spectra of the WS2 NTs. The evolution of new bands was also observed and are associated with Si-CH2-CH2 and, symmetric and assymetric -NH3+ deformation modes (FTIR). Further evidence for functionalization was obtained from zeta potential measurements as there was a change in surface charge from negative for pure WS2 NTs to positive for APTES modified WS2 NTs. Additionally, the thermal stability of APTES was shifted to much higher temperatures as it was bound to the WS2 NTs. The APTES modified WS2 NTs were organophilic and readily dispersed in PLA, while presence of the pendant amine and hydroxyl groups resulted in strong interfacial interactions with the polymer matrix. The inclusion of as little as 0.5 wt% WS2 NTs modified with 2.0 wt% APTES resulted in an increase of 600% in both the elongation at break (a measure of ductility) and the tensile toughness relative to neat PLA, without impacting the stiffness or strength of the polymer.
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Affiliation(s)
- Eimear Magee
- International Institute for Nanocomposites Manufacturing (IINM), University of Warwick, CV4 7AL, UK.
| | | | - Marc Walker
- Department of Physics, University of Warwick, Coventry CV4 7AL, UK
| | - Alla Zak
- Physics Department, Faculty of Sciences, Holon Institute of Technology - HIT, Holon 5810201, Israel
| | - Reshef Tenne
- Molecular Chemistry and Material Science, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Tony McNally
- International Institute for Nanocomposites Manufacturing (IINM), University of Warwick, CV4 7AL, UK.
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Merlini C, Oliveira Castro V, Perli G, El Omari Y, Livi S. Epoxidized Ionic Liquids as Processing Auxiliaries of Poly(Lactic Acid) Matrix: Influence on the Manufacture, Structural and Physical Properties. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:nano13091476. [PMID: 37177021 PMCID: PMC10180299 DOI: 10.3390/nano13091476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2023] [Revised: 04/14/2023] [Accepted: 04/24/2023] [Indexed: 05/15/2023]
Abstract
In this study, we set out to modify poly(lactic acid) (PLA) by incorporating epoxidized ionic liquids (ILs) that were specifically designed with imidazolium-NTf2 moieties. First, we synthesized di-, tri- and tetra-epoxidized ILs, which were incorporated into a PLA matrix at 3, 5, and 10 wt% through a melt extrusion process. We investigated the relationship between the structure and properties of the resulting materials in terms of thermal, mechanical, rheological, and surface properties. The results showed the potential of ILs to impact these properties. Notably, the tri- and tetra-epoxidized ILs enhanced the thermal stability of the PLA matrix as well as the crystallinity while reducing the glass transition temperature and melting point, which is promising for reactive extrusion processing. Overall, this research opens new routes for using reactive ILs to improve the processing and properties of PLA polymers.
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Affiliation(s)
- Claudia Merlini
- Materials Engineering Special Coordination, Federal University of Santa Catarina (UFSC), Blumenau 89036-002, SC, Brazil
- Université de Lyon, CNRS, Université Claude Bernard Lyon 1, INSA Lyon, Université Jean Monnet, UMR 5223, Ingénierie des Matériaux Polymères, CEDEX F-69621 Villeurbanne, France
| | - Vanessa Oliveira Castro
- Université de Lyon, CNRS, Université Claude Bernard Lyon 1, INSA Lyon, Université Jean Monnet, UMR 5223, Ingénierie des Matériaux Polymères, CEDEX F-69621 Villeurbanne, France
- Mechanical Engineering Department, Federal University of Santa Catarina, Florianopolis 88040-900, SC, Brazil
| | - Gabriel Perli
- Université de Lyon, CNRS, Université Claude Bernard Lyon 1, INSA Lyon, Université Jean Monnet, UMR 5223, Ingénierie des Matériaux Polymères, CEDEX F-69621 Villeurbanne, France
| | - Younes El Omari
- Université de Lyon, CNRS, Université Claude Bernard Lyon 1, INSA Lyon, Université Jean Monnet, UMR 5223, Ingénierie des Matériaux Polymères, CEDEX F-69621 Villeurbanne, France
| | - Sébastien Livi
- Université de Lyon, CNRS, Université Claude Bernard Lyon 1, INSA Lyon, Université Jean Monnet, UMR 5223, Ingénierie des Matériaux Polymères, CEDEX F-69621 Villeurbanne, France
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Kumar R, Alex Y, Nayak B, Mohanty S. Effect of poly (ethylene glycol) on 3D printed PLA/PEG blend: A study of physical, mechanical characterization and printability assessment. J Mech Behav Biomed Mater 2023; 141:105813. [PMID: 37015146 DOI: 10.1016/j.jmbbm.2023.105813] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 03/23/2023] [Accepted: 03/26/2023] [Indexed: 04/01/2023]
Abstract
The growing popularity of additive manufacturing in the science, industry is associated with high-quality products for futuristic applications. This study presents an in-depth characterization and analysis of the effect of poly (ethylene glycol) (PEG) having molecular weight 6000 g/mol used with various concentrations (1%,3%,5%) to modify the 3D printed Polylactide (PLA) part. The influence of PEG on the morphology, structure, thermal, wettability and mechanical properties of the 3D-printed PLA/PEG part was investigated. Herein, the mechanical property of injection moulding, 3D printed specimens, and finite element analysis (FEA) simulation results were also compared. The structure and properties of PLA/PEG blends were different from those of virgin PLA. By DSC analysis, it was found that the glass transition temperature (Tg) and cold crystallization temperature decreased in the case of the PLA/PEG blend. From TGA it was observed that PLA/PEG blend was thermally stable. It was shown that with the addition of PEG into PLA the tensile strength and young's modulus decrease, whereas elongation percentage and impact strength increase predominantly. The contact angle results indicate that the addition of PEG lowers the contact angle value of the PLA/PEG blend (from 69.32 ± 1.4° to 45.67 ± 1.2°) and increases surface wettability. With 5% PEG loading, PLA/PEG blend showed optimum structural and mechanical properties together with simple processibility.
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10
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de Alteriis G, Silvestri AT, Conte C, Bottino V, Caputo E, Squillace A, Accardo D, Schiano Lo Moriello R. Innovative Fusion Strategy for MEMS Redundant-IMU Exploiting Custom 3D Components. SENSORS (BASEL, SWITZERLAND) 2023; 23:2508. [PMID: 36904711 PMCID: PMC10007036 DOI: 10.3390/s23052508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 02/10/2023] [Accepted: 02/22/2023] [Indexed: 06/18/2023]
Abstract
In recent years, the overall performances of inertial Micro-Electro Mechanical Sensors (MEMSs) exhibited substantial improvements to values very close or similar to so-called tactical-grade sensors. However, due to their high costs, numerous researchers are currently focusing on the performance enhancement of cheap consumer-grade MEMS inertial sensors for all those applications (as an example, small unmanned aerial vehicles, UAVs), where cost effectiveness is a relevant request; the use of redundancy proves to be a feasible method for this purpose. In this regard, the authors propose, hereinafter, a suitable strategy aimed at fusing raw measurements provided by multiple inertial sensors mounted on a 3D-printed structure. In particular, accelerations and angular rates measured by the sensors are averaged according to weights associated with the results of an Allan variance approach; the lower the noise figure of the sensors, the greater their weight on the final averaged values. On the other hand, possible effects on the measurements due to the use of a 3D structure in reinforced ONYX (a material capable of providing better mechanical specifications for avionic applications with respect to other solutions for additive manufacturing) were evaluated. The performance of a prototype implementing the considered strategy is compared with that of a tactical-grade inertial measurement unit in stationary conditions, exhibiting differences as low as 0.3 degrees in heading measurements. Moreover, the reinforced ONYX structure does not significantly affect the measured values in terms of both thermal and magnetic field while assuring better mechanical characteristics with respect to other 3D printing materials, thanks to a tensile strength of about 250 MPa and a specific stacking sequence of continuous fibers. Finally, a test conducted on an actual UAV highlights performance very close to that of a reference unit, with root-mean-square error in heading measurements as low as 0.3 degrees in observation intervals up to 140 s.
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Affiliation(s)
- Giorgio de Alteriis
- Department of Industrial Engineering, University of Naples Federico II, Piazzale Tecchio 80, 80125 Naples, Italy
| | - Alessia Teresa Silvestri
- Department of Chemical, Materials and Production Engineering, University of Naples Federico II, Piazzale Tecchio 80, 80125 Naples, Italy
| | - Claudia Conte
- Department of Industrial Engineering, University of Naples Federico II, Piazzale Tecchio 80, 80125 Naples, Italy
| | - Verdiana Bottino
- Department of Industrial Engineering, University of Naples Federico II, Piazzale Tecchio 80, 80125 Naples, Italy
| | - Enzo Caputo
- Department of Industrial Engineering, University of Naples Federico II, Piazzale Tecchio 80, 80125 Naples, Italy
| | - Antonino Squillace
- Department of Chemical, Materials and Production Engineering, University of Naples Federico II, Piazzale Tecchio 80, 80125 Naples, Italy
| | - Domenico Accardo
- Department of Industrial Engineering, University of Naples Federico II, Piazzale Tecchio 80, 80125 Naples, Italy
| | - Rosario Schiano Lo Moriello
- Department of Industrial Engineering, University of Naples Federico II, Piazzale Tecchio 80, 80125 Naples, Italy
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11
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Santos-Beneit F, Chen LM, Bordel S, Frutos de la Flor R, García-Depraect O, Lebrero R, Rodriguez-Vega S, Muñoz R, Börner RA, Börner T. Screening Enzymes That Can Depolymerize Commercial Biodegradable Polymers: Heterologous Expression of Fusarium solani Cutinase in Escherichia coli. Microorganisms 2023; 11:microorganisms11020328. [PMID: 36838293 PMCID: PMC9963400 DOI: 10.3390/microorganisms11020328] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Revised: 01/12/2023] [Accepted: 01/17/2023] [Indexed: 01/31/2023] Open
Abstract
In recent years, a number of microbial enzymes capable of degrading plastics have been identified. Biocatalytic depolymerization mediated by enzymes has emerged as a potentially more efficient and environmentally friendly alternative to the currently employed methods for plastic treatment and recycling. However, the functional and systematic study of depolymerase enzymes with respect to the degradation of a series of plastic polymers in a single work has not been widely addressed at present. In this study, the ability of a set of enzymes (esterase, arylesterase and cutinase) to degrade commercial biodegradable polymers (PBS, PBAT, PHB, PHBH, PHBV, PCL, PLA and PLA/PCL) and the effect of pre-treatment methods on their degradation rate was assessed. The degradation products were identified and quantified by HPLC and LC-HRMS analysis. Out of the three enzymes, Fusarium solani cutinase (FsCut) showed the highest activity on grinded PBAT, PBS and PCL after 7 days of incubation. FsCut was engineered and heterologous expressed in Escherichia coli, which conferred the bacterium the capability of degrading solid discs of PBAT and to grow in PBS as the sole carbon source of the medium.
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Affiliation(s)
- Fernando Santos-Beneit
- Institute of Sustainable Processes, Dr. Mergelina s/n, 47011 Valladolid, Spain
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina s/n, 47011 Valladolid, Spain
- Correspondence: (F.S.-B.); (T.B.)
| | - Le Min Chen
- Nestlé Research, Société des Produits Nestlé S.A, Route du Jorat 57, 1000 Lausanne, Switzerland
| | - Sergio Bordel
- Institute of Sustainable Processes, Dr. Mergelina s/n, 47011 Valladolid, Spain
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina s/n, 47011 Valladolid, Spain
| | - Raquel Frutos de la Flor
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina s/n, 47011 Valladolid, Spain
| | - Octavio García-Depraect
- Institute of Sustainable Processes, Dr. Mergelina s/n, 47011 Valladolid, Spain
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina s/n, 47011 Valladolid, Spain
| | - Raquel Lebrero
- Institute of Sustainable Processes, Dr. Mergelina s/n, 47011 Valladolid, Spain
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina s/n, 47011 Valladolid, Spain
| | - Sara Rodriguez-Vega
- Institute of Sustainable Processes, Dr. Mergelina s/n, 47011 Valladolid, Spain
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina s/n, 47011 Valladolid, Spain
| | - Raúl Muñoz
- Institute of Sustainable Processes, Dr. Mergelina s/n, 47011 Valladolid, Spain
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina s/n, 47011 Valladolid, Spain
| | - Rosa Aragão Börner
- Nestlé Research, Société des Produits Nestlé S.A, Route du Jorat 57, 1000 Lausanne, Switzerland
| | - Tim Börner
- Nestlé Research, Société des Produits Nestlé S.A, Route du Jorat 57, 1000 Lausanne, Switzerland
- Correspondence: (F.S.-B.); (T.B.)
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12
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Fryń P, Lalik S, Bogdanowicz KA, Górska N, Iwan A, Marzec M. Degradation of hybrid material l,d-PLA : 5CB : SWCN under the influence of neutral, acidic, and alkaline environments. RSC Adv 2023; 13:3792-3806. [PMID: 36756553 PMCID: PMC9890945 DOI: 10.1039/d2ra05350k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Accepted: 01/10/2023] [Indexed: 01/27/2023] Open
Abstract
The aim of the study was to investigate the influence of the environment's pH on the degradation of the layers of the ternary composite l,d-PLA : 5CB : SWCN (10 : 1 : 0.5, w/w/w), where l,d-PLA (poly(lactic acid)) is a biodegradable polymer, 5CB is a well-known liquid crystal (4'-pentyl-4-biphenylcarbonitrile), and SWCN are single-walled carbon nanotubes. For this purpose, the samples were stored in air, distilled water, and solutions of 0.1 M NaOH and 0.1 M HCl, for up to 62 days. Using differential scanning calorimetry, atomic force microscopy, and infra-red spectroscopy methods it was observed that for both neat l,d-PLA and composite layers there was a poor degradation process after the storage under standard air conditions, distilled water, and 0.1 M HCl solution, while the erosion of the surface layer kept in 0.1 M NaOH solution was revealed just after 6 days. The longer storage in 0.1 M NaOH solution resulted in complete degradation of the l,d-PLA polymer layer, while the composite layer survived for up to 62 days. The solubilization of the polymeric l,d-PLA matrix in the composite after 62 days was so severe that it resulted in the vanishing of thermal effects on the DSC curve except for one that was probably connected with the glass transition of the residual quantity of the polymer that remained in the layer or the isotropisation of 5CB. As a result, we have shown that admixtures of 5CB and SWCN accelerate the degradation of l,d-PLA in the composite layer due to the hydrophilic/hydrophobic interface in the layer and act as plasticizers. The mechanism of the degradation process is also discussed.
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Affiliation(s)
- Patryk Fryń
- Institute of Physics, Jagiellonian University Łojasiewicza 11 30-348 Kraków Poland
| | - Sebastian Lalik
- Institute of Physics, Jagiellonian University Łojasiewicza 11 30-348 Kraków Poland
| | | | - Natalia Górska
- Faculty of Chemistry, Jagiellonian University Gronostajowa 2 30-387 Kraków Poland
| | - Agnieszka Iwan
- Faculty of Security and Safety Research, General Tadeusz Kościuszko Military University of Land Forces Czajkowskiego 109 51-147 Wrocław Poland
| | - Monika Marzec
- Institute of Physics, Jagiellonian University Łojasiewicza 11 30-348 Kraków Poland
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13
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Orellana-Barrasa J, Tarancón S, Pastor JY. Effects of Accelerating the Ageing of 1D PLA Filaments after Fused Filament Fabrication. Polymers (Basel) 2022; 15:polym15010069. [PMID: 36616419 PMCID: PMC9824215 DOI: 10.3390/polym15010069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 12/15/2022] [Accepted: 12/21/2022] [Indexed: 12/28/2022] Open
Abstract
The effects of post-treatment temperature-based methods for accelerating the ageing of PLA were studied on 1D single-PLA filaments after fused filament fabrication (FFF). The goal was to answer the questions whether the PLA can be safely aged-i.e., without degrading-at higher temperatures; at which temperatures, if any; how long it takes for the PLA to fully age at the chosen temperature; and which are the main differences between the material aged at room temperature and the material aged at higher temperatures. We also share other helpful information found. The use of 1D filaments allows for decoupling the variables related to the 3D structure (layer height, raster angle, infill density, and layers adhesion) from the variables solely related to the material (here, we analysed the molecular weight, the molecular orientation, and the crystallinity). 1D PLA filaments were aged at 20, 39, 42, 51, 65, 75, and 80 °C in a water-bath-inspired process in which the hydrolytic degradation of the PLA was minimised for the ageing temperatures of interest. Those temperatures were selected based on a differential scanning calorimetry (DSC) scan of the PLA right after it was printed in order to study the most effective ageing temperature, 39 °C, and highlight possible degradation mechanisms during ageing. The evolution of the thermal and mechanical properties of the PLA filaments at different temperatures was recorded and compared with those of the material aged at room temperature. A DSC scan was used to evaluate the thermal and physical properties, in which the glass transition, enthalpic relaxation, crystallisation, and melting reactions were analysed. A double glass transition was found, and its potential implications for the scientific community are discussed. Tensile tests were performed to evaluate the tensile strength and elastic modulus. The flow-induced molecular orientation, the degradation, the logistic fitting, and the so-called summer effect-the stabilisation of properties at higher values when aged at higher temperatures-are discussed to assess the safety of accelerating the ageing rate and the differences between the materials aged at different temperatures. It was found that the PLA aged at 39 °C (1) reached almost stable properties with just one day of ageing, i.e., the ageing rate accelerated by 875% for the elastic modulus and by 1635% for the yield strength; (2) the stable properties were higher than those from the PLA aged at room temperature; and (3) no signs of degradation were identified for the ageing temperature of interest.
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14
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Rogkotis K, Matsia S, Likotrafiti E, Rhoades J, Kountouras D, Katakalos K, Pavlidou E, Ritzoulis C, Salifoglou A. Selective antimicrobial food packaging of composite poly(lactic acid) cobalt-citrate films. Food Packag Shelf Life 2022. [DOI: 10.1016/j.fpsl.2022.100959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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15
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Balakrishnan NK, Siebert S, Richter C, Groten R, Seide G. Effect of Colorants and Process Parameters on the Properties of Dope-Dyed Polylactic Acid Multifilament Yarns. Polymers (Basel) 2022; 14:polym14225021. [PMID: 36433148 PMCID: PMC9692423 DOI: 10.3390/polym14225021] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2022] [Revised: 11/13/2022] [Accepted: 11/16/2022] [Indexed: 11/22/2022] Open
Abstract
The color of textile fibers is typically imparted by submersion in a high-temperature dye bath. However, the treatment of the effluent is challenging and the textile industry is therefore a major source of water pollution. Current fashion trends favor biobased polymers such as polylactic acid (PLA) but exhaust dyeing at high temperatures causes hydrolytic degradation, reducing the crystallinity and tenacity of the yarn. To preserve the mechanical properties of PLA-based textiles, an alternative to exhaust dyeing called dope dyeing can be used, wherein colorants are incorporated into the polymer matrix during melt spinning. We evaluated this process by dope dyeing PLA with several colorants, then testing the thermal, physical, and mechanical properties of the yarn and the physical properties of circular-knitted fabrics. Although the colorants affected the crystallization behavior at lower cooling rates, during the melt-spinning process, the drawing speed had a greater effect on the crystallinity and mechanical properties of the dyed yarn. Scanning electron microscopy revealed that the colorants were well dispersed in the PLA matrix. We found that the colorants did not affect the physical properties of the knitted fabric. Our results can be used to develop more environmentally beneficial dope-dyed PLA yarn with improved mechanical properties.
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Affiliation(s)
- Naveen Kumar Balakrishnan
- Aachen-Maastricht Institute for Biobased Materials (AMIBM), Maastricht University, Brightlands Chemelot Campus, Urmonderbaan 22, 6167 RD Geleen, The Netherlands
| | - Stefan Siebert
- Aachen-Maastricht Institute for Biobased Materials (AMIBM), Maastricht University, Brightlands Chemelot Campus, Urmonderbaan 22, 6167 RD Geleen, The Netherlands
| | - Christoph Richter
- Department of Textile and Clothing Technology, Niederrhein University of Applied Sciences, Campus Moenchengladbach, Webschulstrasse 31, 41065 Moenchengladbach, Germany
| | - Robert Groten
- Department of Textile and Clothing Technology, Niederrhein University of Applied Sciences, Campus Moenchengladbach, Webschulstrasse 31, 41065 Moenchengladbach, Germany
| | - Gunnar Seide
- Aachen-Maastricht Institute for Biobased Materials (AMIBM), Maastricht University, Brightlands Chemelot Campus, Urmonderbaan 22, 6167 RD Geleen, The Netherlands
- Correspondence:
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16
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Pilarska AA, Bula K, Pilarski K, Adamski M, Wolna-Maruwka A, Kałuża T, Magda P, Boniecki P. Polylactide (PLA) as a Cell Carrier in Mesophilic Anaerobic Digestion-A New Strategy in the Management of PLA. MATERIALS (BASEL, SWITZERLAND) 2022; 15:8113. [PMID: 36431599 PMCID: PMC9697477 DOI: 10.3390/ma15228113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 11/10/2022] [Accepted: 11/13/2022] [Indexed: 06/16/2023]
Abstract
The management of waste polylactide (PLA) in various solutions of thermophilic anaerobic digestion (AD) is problematic and often uneconomical. This paper proposes a different approach to the use of PLA in mesophilic AD, used more commonly on the industrial scale, which consists of assigning the function of a microbial carrier to the biopolymer. The study involved the testing of waste wafers and waste wafers and cheese in a co-substrate system, combined with digested sewage sludge. The experiment was conducted on a laboratory scale, in a batch bioreactor mode. They were used as test samples and as samples with the addition of a carrier: WF-control and WFC-control; WF + PLA and WFC + PLA. The main objective of the study was to verify the impact of PLA in the granular (PLAG) and powder (PLAP) forms on the stability and efficiency of the process. The results of the analysis of physicochemical properties of the carriers, including the critical thermal analysis by differential scanning calorimetry (DSC), as well as the amount of cellular biomass of Bacillus amyloliquefaciens obtained in a culture with the addition of the tested PLAG and PLAP, confirmed that PLA can be an effective cell carrier in mesophilic AD. The addition of PLAG produced better results for bacterial proliferation than the addition of powdered PLA. The highest level of dehydrogenase activity was maintained in the WFC + PLAG system. An increase in the volume of the methane produced for the samples digested with the PLA granules carrier was registered in the study. It went up by c.a. 26% for WF, from 356.11 m3 Mg-1 VS (WF-control) to 448.84 m3 Mg-1 VS (WF + PLAG), and for WFC, from 413.46 m3 Mg-1 VS, (WFC-control) to 519.98 m3 Mg-1 VS (WFC + PLAG).
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Affiliation(s)
- Agnieszka A. Pilarska
- Department of Hydraulic and Sanitary Engineering, Poznań University of Life Sciences, Piątkowska 94A, 60-649 Poznan, Poland
| | - Karol Bula
- Institute of Materials Technology, Faculty of Mechanical Engineering, Poznan University of Technology, 60-965 Poznan, Poland
| | - Krzysztof Pilarski
- Department of Biosystems Engineering, Poznań University of Life Sciences, Wojska Polskiego 50, 60-627 Poznan, Poland
| | - Mariusz Adamski
- Department of Biosystems Engineering, Poznań University of Life Sciences, Wojska Polskiego 50, 60-627 Poznan, Poland
| | - Agnieszka Wolna-Maruwka
- Department of Soil Science and Microbiology, Poznań University of Life Sciences, Szydłowska 50, 60-656 Poznan, Poland
| | - Tomasz Kałuża
- Department of Hydraulic and Sanitary Engineering, Poznań University of Life Sciences, Piątkowska 94A, 60-649 Poznan, Poland
| | - Przemysław Magda
- Department of Wastewater Treatment, Aquanet S.A., Gdyńska 1, 61-477 Poznań, Poland
| | - Piotr Boniecki
- Department of Biosystems Engineering, Poznań University of Life Sciences, Wojska Polskiego 50, 60-627 Poznan, Poland
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17
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Naseem R, Montalbano G, German MJ, Ferreira AM, Gentile P, Dalgarno K. Influence of PCL and PHBV on PLLA Thermal and Mechanical Properties in Binary and Ternary Polymer Blends. Molecules 2022; 27:7633. [PMID: 36364463 PMCID: PMC9657691 DOI: 10.3390/molecules27217633] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 11/01/2022] [Accepted: 11/04/2022] [Indexed: 01/15/2024] Open
Abstract
PLLA, PCL and PHBV are aliphatic polyesters which have been researched and used in a wide range of medical devices, and all three have advantages and disadvantages for specific applications. Blending of these materials is an attractive way to make a material which overcomes the limitations of the individual polymers. Both PCL and PHBV have been evaluated in polymer blends with PLLA in order to provide enhanced properties for specific applications. This paper explores the use of PCL and PHBV together with PLLA in ternary blends with assessment of the thermal, mechanical and processing properties of the resultant polymer blends, with the aim of producing new biomaterials for orthopaedic applications. DSC characterisation is used to demonstrate that the materials can be effectively blended. Blending PCL and PHBV in concentrations of 5-10% with PLLA produces materials with average modulus improved by up to 25%, average strength improved by up to 50% and average elongation at break improved by 4000%, depending on the concentrations of each polymer used. PHBV impacts most on the modulus and strength of the blends, whilst PCL has a greater impact on creep behaviour and viscosity. Blending PCL and PHBV with PLLA offers an effective approach to the development of new polyester-based biomaterials with combinations of mechanical properties which cannot be provided by any of the materials individually.
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Affiliation(s)
- Raasti Naseem
- School of Engineering, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
| | - Giorgia Montalbano
- Department of Applied Science and Technology, Politecnico di Torino, 10129 Torino, Italy
| | - Matthew J. German
- School of Dental Sciences, Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
| | - Ana M. Ferreira
- School of Engineering, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
| | - Piergiorgio Gentile
- School of Engineering, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
| | - Kenneth Dalgarno
- School of Engineering, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
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18
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Hashem HM, Motawea A, Kamel AH, Bary EMA, Hassan SSM. Fabrication and characterization of electrospun nanofibers using biocompatible polymers for the sustained release of venlafaxine. Sci Rep 2022; 12:18037. [PMID: 36302929 PMCID: PMC9614003 DOI: 10.1038/s41598-022-22878-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 10/20/2022] [Indexed: 01/24/2023] Open
Abstract
Recently, drug-controlled release nanotechnology has gained special attention in biomedicine. This work focuses on developing novel electrospun polymeric nanofibers (NFs) for buccal delivery of VEN to avoid the hepatic metabolism and enzymatic degradation in the GIT and develop an effective control of drug release. The optimized NFs were obtained by blending polylactic acid (PLA), and poly (ɛ-caprolactone) (PCL) fixed at a ratio of 1:1. It was characterized for morphology, drug-loading, FTIR, XRD, DSC, and in vitro drug release. Ex vivo permeability of the blend NFs was assessed using chicken pouch mucosa compared to VEN suspension, followed by histopathological examination. Further, the cytotoxic effect in three different cell lines using WST-1 assay. SEM morphologies refer to defect-free uniform NFs of PLA, PCL, and PLA/PCL mats. These fibers had a diameter ranging from 200 to 500 nm. The physico-thermal characterization of NFs depicted that the drug was successfully loaded and in an amorphous state in the PLA/PCL NFs. In vitro release of NFs substantiated a bi-phasic profile with an initial burst release of about 30% in the initial 0.5 h and a prolonged cumulative release pattern that reached 80% over 96 h following a non-Fickian diffusion mechanism. Ex vivo permeation emphasizes the major enhancement of the sustained drug release and the noticeable decrease in the permeability of the drug from NFs. Cytotoxicity data found that IC50 of VEN alone was 217.55 μg/mL, then VEN-NFs recorded an IC50 value of 250.62 μg/mL, and plain NFs showed the lowest toxicity and IC50 440.48 μg/mL in oral epithelial cells (OEC). Histopathology and cell toxicity studies demonstrated the preserved mucosal architecture and the preclinical safety. The developed PLA/PCL NFs can be promising drug carriers to introduce a step-change in improved psychiatric treatment healthcare.
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Affiliation(s)
- Heba M. Hashem
- grid.10251.370000000103426662Pharmaceutical Analytical Chemistry Department, Faculty of Pharmacy, Mansoura University, Mansoura, 35516 Egypt
| | - Amira Motawea
- grid.10251.370000000103426662Pharmaceutics Department, Faculty of Pharmacy, Mansoura University, Mansoura, 35516 Egypt
| | - Ayman H. Kamel
- grid.7269.a0000 0004 0621 1570Chemistry Department, Faculty of Science, Ain Shams University, Abbasia, 11566 Cairo Egypt ,grid.413060.00000 0000 9957 3191Chemistry Department, College of Science, Bahrain University, Sakhir, 32038 Bahrain
| | - E. M. Abdel Bary
- grid.10251.370000000103426662Chemistry Department, Faculty of Science, Mansoura University, Mansoura, 35516 Egypt
| | - Saad S. M. Hassan
- grid.7269.a0000 0004 0621 1570Chemistry Department, Faculty of Science, Ain Shams University, Abbasia, 11566 Cairo Egypt
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19
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Influence of Ceramic Particles Size and Ratio on Surface-Volume Features of the Naturally Derived HA-Reinforced Filaments for Biomedical Applications. J Funct Biomater 2022; 13:jfb13040199. [PMID: 36278668 PMCID: PMC9590078 DOI: 10.3390/jfb13040199] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 10/18/2022] [Accepted: 10/19/2022] [Indexed: 11/06/2022] Open
Abstract
The intersection of the bone tissue reconstruction and additive manufacturing fields promoted the advancement to a prerequisite and new feedstock resource for high-performance bone-like-scaffolds manufacturing. In this paper, the proposed strategy was directed toward the use of bovine-bone-derived hydroxyapatite (HA) for surface properties enhancement and mechanical features reinforcement of the poly(lactic acid) matrix for composite filaments extrusion. The involvement of completely naturally derived materials in the technological process was based on factors such as sustainability, low cost, and a facile and green synthesis route. After the HA isolation and extraction from bovine bones by thermal processing, milling, and sorting, two dependent parameters—the HA particles size (<40 μm, <100 μm, and >125 μm) and ratio (0−50% with increments of 10%)—were simultaneously modulated for the first time during the incorporation into the polymeric matrix. The resulting melt mixtures were divided for cast pellets and extruded filaments development. Based on the obtained samples, the study was further designed to examine several key features by complementary surface−volume characterization techniques. Hence, the scanning electron microscopy and micro-CT results for all specimens revealed a uniform and homogenous dispersion of HA particles and an adequate adhesion at the ceramic/polymer interface, without outline pores, sustained by the shape and surface features of the synthesized ceramic particles. Moreover, an enhanced wettability (contact angle in the ~70−21° range) and gradual mechanical takeover were indicated once the HA ratio increased, independent of the particles size, which confirmed the benefits and feasibility of evenly blending the natural ceramic/polymeric components. The results correlation led to the selection of optimal technological parameters for the synthesis of adequate composite filaments destined for future additive manufacturing and biomedical applications.
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20
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Graphene Nanoplatelets' Effect on the Crystallization, Glass Transition, and Nanomechanical Behavior of Poly(ethylene 2,5-furandicarboxylate) Nanocomposites. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27196653. [PMID: 36235190 PMCID: PMC9571983 DOI: 10.3390/molecules27196653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 09/25/2022] [Accepted: 10/03/2022] [Indexed: 11/07/2022]
Abstract
Poly(ethylene 2,5-furandicarboxylate) (PEF) nanocomposites reinforced with various content of graphene nanoplatelets (GNPs) were synthesized in situ in this work. PEF is a widely known biobased polyester with promising physical properties and is considered as the sustainable counterpart of PET. Despite its exceptional gas barrier and mechanical properties, PEF presents with a low crystallization rate. In this context, a small number of GNPs were incorporated into the material to facilitate the nucleation and overall crystallization of the matrix. Kinetic analysis of both the cold and melt crystallization processes of the prepared materials was achieved by means of differential scanning calorimetry (DSC). The prepared materials’ isothermal crystallization from the glass and melt states was studied using the Avrami and Hoffman–Lauritzen theories. The Dobreva method was applied for the non-isothermal DSC measurements to calculate the nucleation efficiency of the GNPs on the PEF matrix. Furthermore, Vyazovkin’s isoconversional method was employed to estimate the effective activation energy values of the amorphous materials’ glass transition. Finally, the nanomechanical properties of the amorphous and semicrystalline PEF materials were evaluated via nanoindentation measurements. It is shown that the GNPs facilitate the crystallization process through heterogeneous nucleation and, at the same time, improve the nanomechanical behavior of PEF, with the semicrystalline samples presenting with the larger enhancements.
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21
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Sharma S, Mudgal D, Gupta V. Polydopamine coating on additive manufacturing‐based poly lactic acid structures with controllable parameters for enhanced mechanical properties: An experimental investigation. POLYM ENG SCI 2022. [DOI: 10.1002/pen.26124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Shrutika Sharma
- Mechanical Engineering Department Thapar Institute of Engineering and Technology Patiala Punjab India
| | - Deepa Mudgal
- Mechanical Engineering Department Thapar Institute of Engineering and Technology Patiala Punjab India
| | - Vishal Gupta
- Mechanical Engineering Department Thapar Institute of Engineering and Technology Patiala Punjab India
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22
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Characterization of 3D Printed Polylactic Acid by Fused Granular Fabrication through Printing Accuracy, Porosity, Thermal and Mechanical Analyses. Polymers (Basel) 2022; 14:polym14173530. [PMID: 36080605 PMCID: PMC9460545 DOI: 10.3390/polym14173530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2022] [Revised: 08/20/2022] [Accepted: 08/22/2022] [Indexed: 11/16/2022] Open
Abstract
Fused Granular Fabrication (FGF) or screw-extrusion based 3D printing for polymers is a less diffused alternative to filament-based Additive Manufacturing (AM). Its greatest advantage lies in superior sustainability; in fact, polymer granules can be used to directly feed an FGF printer, reducing the time, cost and energy of producing a part. Moreover, with this technology, a circular economy approach involving the use of pellets made from plastic waste can be easily implemented. Polylactic Acid (PLA) pellets were processed at different printing speeds and with different infill percentages on a customized version of a commercial Prusa i3 Plus 3D printer modified with a Mahor screw extruder. For the characterization of the 3D printed samples, rheological, thermal, mechanical and porosity analyses were carried out. In addition, the energy consumption of the 3D printer was monitored during the production of the specimens. The results showed that a higher printing speed leads to lower energy consumption, without compromising material strength, whereas a slower printing speed is preferable to increase material stiffness.
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23
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Alexeeva O, Olkhov A, Konstantinova M, Podmasterev V, Tretyakov I, Petrova T, Koryagina O, Lomakin S, Siracusa V, Iordanskii AL. Improvement of the Structure and Physicochemical Properties of Polylactic Acid Films by Addition of Glycero-(9,10-trioxolane)-Trialeate. Polymers (Basel) 2022; 14:polym14173478. [PMID: 36080553 PMCID: PMC9460106 DOI: 10.3390/polym14173478] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 08/15/2022] [Accepted: 08/22/2022] [Indexed: 12/01/2022] Open
Abstract
Glycero-(9,10-trioxolane)-trioleate (ozonide of oleic acid triglyceride, OTOA) was introduced into polylactic acid (PLA) films in amounts of 5, 10, 30, 50, and 70% w/w. The morphological, mechanical, thermal, and water absorption properties of PLA films after the OTOA addition were studied. The morphological analysis of the films showed that the addition of OTOA increased the diameter of PLA spherulites and, as a consequence, increased the proportion of amorphous regions in PLA films. A study of the thermodynamic properties of PLA films by differential scanning calorimetry (DSC) demonstrated a decrease in the glass transition temperature of the films with an increase in the OTOA content. According to DSC and XRD data, the degree of crystallinity of the PLA films showed a tendency to decrease with an increase in the OTOA content in the films, which could be accounted for the plasticizing effect of OTOA. The PLA film with 10% OTOA content was characterized by good smoothness, hydrophobicity, and optimal mechanical properties. Thus, while maintaining high tensile strength of 21 MPa, PLA film with 10% OTOA showed increased elasticity with 26% relative elongation at break, as compared to the 2.7% relative elongation for pristine PLA material. In addition, DMA method showed that PLA film with 10% OTOA exhibits increased strength characteristics in the dynamic load mode. The resulting film materials based on optimized PLA/OTOA compositions could be used in various packaging and biomedical applications.
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Affiliation(s)
- Olga Alexeeva
- N.M. Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, 119334 Moscow, Russia
- Correspondence: (O.A.); (V.S.); (A.L.I.)
| | - Anatoliy Olkhov
- N.M. Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, 119334 Moscow, Russia
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991 Moscow, Russia
- Academic Department of Innovational Materials and Technologies Chemistry, Plekhanov Russian University of Economics, 117997 Moscow, Russia
| | - Marina Konstantinova
- N.M. Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, 119334 Moscow, Russia
| | - Vyacheslav Podmasterev
- N.M. Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, 119334 Moscow, Russia
| | - Ilya Tretyakov
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991 Moscow, Russia
| | - Tuyara Petrova
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991 Moscow, Russia
| | - Olga Koryagina
- N.M. Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, 119334 Moscow, Russia
| | - Sergey Lomakin
- N.M. Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, 119334 Moscow, Russia
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991 Moscow, Russia
| | - Valentina Siracusa
- Department of Chemical Science (DSC), University of Catania, Viale A. Doria 6, 95125 Catania, Italy
- Correspondence: (O.A.); (V.S.); (A.L.I.)
| | - Alexey L. Iordanskii
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991 Moscow, Russia
- Correspondence: (O.A.); (V.S.); (A.L.I.)
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Ibrahim E, Ahmed S, Abir SSH, Taylor K, Padilla-Gainza VM, Lozano K. Centrifugally spun alginate-poly(lactic acid) microbeads: A promising carrier for drug delivery and tissue engineering. Int J Biol Macromol 2022; 220:671-682. [PMID: 35988730 DOI: 10.1016/j.ijbiomac.2022.08.097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2022] [Revised: 08/12/2022] [Accepted: 08/13/2022] [Indexed: 11/05/2022]
Abstract
A facile and high yield centrifugal spinning technique known as Forcespinning® (FS) was used to develop unique microstructures consisting of PLA microbeads along alginate fibers. Morphological variation and structural features appeared in the field-emission scanning electron micrographs for the PLA-alginate composites and dried PLA-alginate films from precursor emulsions at constant PLA and varied alginate contents. Shrunk and deflated microbeads were observed for composites whilst spherical beads were evident for the PLA control. Furthermore, PLA was found surrounding the alginate when the alginate was present at 0.24 wt% or lower, while alginate (mushroom-like structures), were seen protruding through the PLA layer at ≥0.34 wt% alginate. Rheological characterization of the composite emulsions revealed that the filler (alginate) provided shear thinning properties including pseudoplasticity, desirable for printing and other related applications in contrast to the Newtonian flow shown by the PLA control. Along with infra-red spectroscopy, the nanocomposites were further characterized using thermal gravimetry and differential scanning calorimetry featuring reversible events influenced by heat capacity and irreversible kinetic/thermodynamic counterparts. The work provides a comprehensive investigation of biocompatible networks of PLA-alginate microbeads embedded in nano-sized fibers and the prospective application of these microbeads as a drug delivery system.
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Affiliation(s)
- Eman Ibrahim
- Department of Mechanical Engineering, University of Texas Rio Grande Valley, Edinburg, TX 78539, USA.
| | - Salahuddin Ahmed
- Department of Mechanical Engineering, University of Texas Rio Grande Valley, Edinburg, TX 78539, USA
| | - Sk Shamim Hasan Abir
- Department of Mechanical Engineering, University of Texas Rio Grande Valley, Edinburg, TX 78539, USA
| | - Keith Taylor
- Department of Chemistry and Biochemistry, University of Windsor, Windsor, Ontario N9B 3P4, Canada
| | - Victoria M Padilla-Gainza
- Department of Mechanical Engineering, University of Texas Rio Grande Valley, Edinburg, TX 78539, USA
| | - Karen Lozano
- Department of Mechanical Engineering, University of Texas Rio Grande Valley, Edinburg, TX 78539, USA
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25
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Lupu (Luchian) AM, Mariş M, Zaharescu T, Marinescu VE, Iovu H. Stability Study of the Irradiated Poly(lactic acid)/Styrene Isoprene Styrene Reinforced with Silica Nanoparticles. MATERIALS 2022; 15:ma15145080. [PMID: 35888545 PMCID: PMC9319368 DOI: 10.3390/ma15145080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Revised: 07/04/2022] [Accepted: 07/12/2022] [Indexed: 11/16/2022]
Abstract
In this paper, the stability improvement of poly(lactic acid) (PLA)/styrene-isoprene block copolymer (SIS) loaded with silica nanoparticles is characterized. The protection efficiency in the material of thermal stability is mainly studied by means of high accurate isothermal and nonisothermal chemiluminescence procedures. The oxidation induction times obtained in the isothermal CL determinations increase from 45 min to 312 min as the polymer is free of silica or the filler loading is about 10%, respectively. The nonisothermal measurements reveal the values of onset oxidation temperatures with about 15% when the concentration of SiO2 particles is enhanced from none to 10%. The curing assay and Charlesby–Pinner representation as well as the modifications that occurred in the FTIR carbonyl band at 1745 cm−1 are appropriate proofs for the delay of oxidation in hybrid samples. The improved efficiency of silica during the accelerated degradation of PLA/SIS 30/n-SiO2 composites is demonstrated by means of the increased values of activation energy in correlation with the augmentation of silica loading. While the pristine material is modified by the addition of 10% silica nanoparticles, the activation energy grows from 55 kJ mol−1 to 74 kJ mol−1 for nonirradiated samples and from 47 kJ mol−1 to 76 kJ mol−1 for γ-processed material at 25 kGy. The stabilizer features are associated with silica nanoparticles due to the protection of fragments generated by the scission of hydrocarbon structure of SIS, the minor component, whose degradation fragments are early converted into hydroperoxides rather than influencing depolymerization in the PLA phase. The reduction of the transmission values concerning the growing reinforcement is evidence of the capacity of SiO2 to minimize the changes in polymers subjected to high energy sterilization. The silica loading of 10 wt% may be considered a proper solution for attaining an extended lifespan under the accelerated degradation caused by the intense transfer of energy, such as radiation processing on the polymer hybrid.
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Affiliation(s)
- Ana Maria Lupu (Luchian)
- Advanced Polymer Materials Group, University Politehnica of Bucharest, 011061 Bucharest, Romania; (A.M.L.); (H.I.)
- Extreme Light Infrastructure-Nuclear Physics (ELI-NP), Horia Hulubei National Institute for Physics and Nuclear Engineering (IFIN-HH), 077125 Magurele, Romania
| | - Marius Mariş
- Dental Medicine Faculty, University Titu Maiorescu, 22 Dâmbovnicului Tineretului St., 040441 Bucharest, Romania
- Correspondence: (M.M.); (T.Z.)
| | - Traian Zaharescu
- INCDIE ICPE CA, Radiochemistry Center, 313 Splaiul Unirii, 030138 Bucharest, Romania;
- Correspondence: (M.M.); (T.Z.)
| | | | - Horia Iovu
- Advanced Polymer Materials Group, University Politehnica of Bucharest, 011061 Bucharest, Romania; (A.M.L.); (H.I.)
- Academy of Romanian Scientists, 050094 Bucharest, Romania
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26
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Hybrid biodegradable electrospun scaffolds based on poly(l-lactic acid) and reduced graphene oxide with improved piezoelectric response. Polym J 2022. [DOI: 10.1038/s41428-022-00669-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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27
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Lozano Fernandez ME, Miskolczi N. Production of Cellulose Nano-Fibers and Its Application in Poly-Lactic-Acid: Property Improvement by New Types of Coupling Agents. Polymers (Basel) 2022; 14:1887. [PMID: 35567056 PMCID: PMC9104889 DOI: 10.3390/polym14091887] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2022] [Revised: 04/26/2022] [Accepted: 04/28/2022] [Indexed: 02/04/2023] Open
Abstract
Poly-lactic-acid is a biopolymer that can be an attractive alternative to replace petroleum-based polymers. It has advanced mechanical properties, melts easily with less energy consumption, and can be used to produce biodegradable plastics using renewable sources. However, some of the properties of poly-lactic-acid are inferior to those of traditional polymers: e.g., intensive farming is necessary for high agricultural yield, the composting needs special conditions, it is difficult to blend with other commonly used plastics, expensive, high permeability, etc. Therefore, the present work seeks to improve the structure and mechanical properties of the poly-lactic-acid incorporated by cellulose nano-fibers obtained from rice straw by a chemical acidic treatment. The fibers were incorporated into the poly-lactic-acid polymer matrix in a concentration of 1% by two-roll mill. To improve the incorporation of the fibers in the matrix, different coupling agents were used: PE-g-MA, vinyl trimethoxy silane, polyethylene-glycol with different molecular weight, and two types of experimentally synthetized α-olefin-maleic anhydride-based copolymers. The properties of the final composite could be improved, however those depend on the coupling agent to be used. The improving effect of the tested chemicals had been depended on the temperature. Based on structure analysis, both chemical and physical interactions were proposed between the cellulose nanofiber and polymer matrix. The thermogravimetric and viscosity results well represented the softener effect of the used chemical agents.
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Affiliation(s)
| | - Norbert Miskolczi
- Research Centre of Biochemical, Environmental and Chemical Engineering, MOL Department of Hydrocarbon & Coal Processing, Faculty of Engineering, University of Pannonia, Egyetem u. 10, H-8200 Veszprém, Hungary;
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28
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Cvek M, Paul UC, Zia J, Mancini G, Sedlarik V, Athanassiou A. Biodegradable Films of PLA/PPC and Curcumin as Packaging Materials and Smart Indicators of Food Spoilage. ACS APPLIED MATERIALS & INTERFACES 2022; 14:14654-14667. [PMID: 35302368 PMCID: PMC8972250 DOI: 10.1021/acsami.2c02181] [Citation(s) in RCA: 37] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Bio-based and biodegradable packaging combined with chemical sensors and indicators has attracted great attention as they can provide protection combined with information on the actual freshness of foodstuffs. In this study, we present an effective, biodegradable, mostly bio-sourced material ideal for sustainable packaging that can also be used as a smart indicator of ammonia (NH3) vapor and food spoilage. The developed material comprises a blend of poly(lactic acid) (PLA) and poly(propylene carbonate) (PPC) loaded with curcumin (CCM), which is fabricated via the scalable techniques of melt extrusion and compression molding. Due to the structural similarity of PLA and PPC, they exhibited good compatibility and formed hydrogen bonds within their blends, as proven by Fourier transform infrared (FTIR) and X-ray diffraction (XRD). Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) analysis confirmed that the blends were thermally stable at the used processing temperature (180 °C) with minimal crystallinity. The rheological and mechanical properties of the PLA/PPC blends were easily tuned by changing the ratio of the biopolymers. Supplementing the PLA/PCC samples with CCM resulted in efficient absorption of UV radiation, yet the transparency of the films was preserved (T700 ∼ 68-84%). The investigation of CCM extract in ethanol with the DPPH• assay demonstrated that the samples could also provide effective antioxidant action, due to the tunable release of the CCM. Analyses for water vapor and oxygen permeability showed that the PPC improved the barrier properties of the PLA/PPC blends, while the presence of CCM did not hinder barrier performance. The capacity for real-time detection of NH3 vapor was quantified using the CIELab color space analysis. A change in color of the sample from a yellowish shade to red was observed by the naked eye. Finally, a film of PLA/PPC/CCM was successfully applied as a sticker indicator to monitor the spoilage of shrimps over time, demonstrating an evident color change from yellow to light orange, particularly for the PPC-containing blend. The developed system, therefore, has the potential to serve as a cost-effective, easy-to-use, nondestructive, smart indicator for food packaging, as well as a means for NH3 gas monitoring in industrial and environmental applications.
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Affiliation(s)
- Martin Cvek
- Centre
of Polymer Systems, University Institute, Tomas Bata University in Zlin, Trida T. Bati 5678, 760 01 Zlin, Czech Republic
| | - Uttam C. Paul
- Smart
Materials, Istituto Italiano di Tecnologia, Via Morego 30, 161 63 Genoa, Italy
| | - Jasim Zia
- Smart
Materials, Istituto Italiano di Tecnologia, Via Morego 30, 161 63 Genoa, Italy
| | - Giorgio Mancini
- Smart
Materials, Istituto Italiano di Tecnologia, Via Morego 30, 161 63 Genoa, Italy
| | - Vladimir Sedlarik
- Centre
of Polymer Systems, University Institute, Tomas Bata University in Zlin, Trida T. Bati 5678, 760 01 Zlin, Czech Republic
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29
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Perin D, Fredi G, Rigotti D, Soccio M, Lotti N, Dorigato A. Sustainable textile fibers of bioderived polylactide/poly(pentamethylene 2,
5‐furanoate
) blends. J Appl Polym Sci 2022. [DOI: 10.1002/app.51740] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Davide Perin
- Department of Industrial Engineering and INSTM Research Unit University of Trento Trento Italy
| | - Giulia Fredi
- Department of Industrial Engineering and INSTM Research Unit University of Trento Trento Italy
| | - Daniele Rigotti
- Department of Industrial Engineering and INSTM Research Unit University of Trento Trento Italy
| | - Michelina Soccio
- Department of Civil, Chemical, Environmental, and Materials Engineering University of Bologna Bologna Italy
| | - Nadia Lotti
- Department of Civil, Chemical, Environmental, and Materials Engineering University of Bologna Bologna Italy
| | - Andrea Dorigato
- Department of Industrial Engineering and INSTM Research Unit University of Trento Trento Italy
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30
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Modified Poly(Lactic Acid) Epoxy Resin Using Chitosan for Reactive Blending with Epoxidized Natural Rubber: Analysis of Annealing Time. Polymers (Basel) 2022; 14:polym14061085. [PMID: 35335415 PMCID: PMC8949308 DOI: 10.3390/polym14061085] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 03/04/2022] [Accepted: 03/04/2022] [Indexed: 02/05/2023] Open
Abstract
Poly(lactic acid) was melt-blended with epoxy resin without hardener and chitosan (CTS) to prepare modified PLA (PLAEC). Epoxy resin 5% and CTS 1–20% (wt/wt) were incorporated into PLA during melt mixing. PLAEC was melt-blended with an epoxidized natural rubber (ENR) 80/20 wt. The PLAEC CTS 1% blended with ENR (PLAEC1/ENR) showed a high tensile strength (30 MPa) and elongation at break (7%). The annealing process at 80 °C for 0–15 min maintained a tensile strength of approximately 30 MPa. SEM images of the PLAE/ENR blend showed phase inversion from co-continuous to ENR particle dispersion in the PLA matrix with the addition of CTS, whereas the annealing time reduced the hole sizes of the extracted ENR phase due to the shrinkage of PLA by crystallization. Thermal properties were observed by DSC and a Vicat softening test. The annealing process increased the crystallinity and Vicat softening temperature of the PLAEC1/ENR blend. Reactions of −COOH/epoxy groups and epoxy/−NH2 groups occurred during PLAE and PLAEC preparation, respectively. FTIR confirmed the reaction between the −NH2 groups of CTS in PLAEC and the epoxy groups of ENR. This reaction increased the mechanical properties, while the annealing process improved the morphology and thermal properties of the blend.
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31
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Kelava L, Ivić I, Pakai E, Fekete K, Maroti P, Told R, Ujfalusi Z, Garami A. Stereolithography 3D Printing of a Heat Exchanger for Advanced Temperature Control in Wire Myography. Polymers (Basel) 2022; 14:polym14030471. [PMID: 35160461 PMCID: PMC8839612 DOI: 10.3390/polym14030471] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 01/16/2022] [Accepted: 01/20/2022] [Indexed: 12/24/2022] Open
Abstract
We report the additive manufacturing of a heat-exchange device that can be used as a cooling accessory in a wire myograph. Wire myography is used for measuring vasomotor responses in small resistance arteries; however, the commercially available devices are not capable of active cooling. Here, we critically evaluated a transparent resin material, in terms of mechanical, structural, and thermal behavior. Tensile strength tests (67.66 ± 1.31 MPa), Charpy impact strength test (20.70 ± 2.30 kJ/m2), and Shore D hardness measurements (83.0 ± 0.47) underlined the mechanical stability of the material, supported by digital microscopy, which revealed a glass-like structure. Differential scanning calorimetry with thermogravimetry analysis and thermal conductivity measurements showed heat stability until ~250 °C and effective heat insulation. The 3D-printed heat exchanger was tested in thermophysiology experiments measuring the vasomotor responses of rat tail arteries at different temperatures (13, 16, and 36 °C). The heat-exchange device was successfully used as an accessory of the wire myograph system to cool down the experimental chambers and steadily maintain the targeted temperatures. We observed temperature-dependent differences in the vasoconstriction induced by phenylephrine and KCl. In conclusion, the transparent resin material can be used in additive manufacturing of heat-exchange devices for biomedical research, such as wire myography. Our animal experiments underline the importance of temperature-dependent physiological mechanisms, which should be further studied to understand the background of the thermal changes and their consequences.
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Affiliation(s)
- Leonardo Kelava
- Department of Thermophysiology, Institute for Translational Medicine, Medical School, University of Pecs, H-7624 Pecs, Hungary
| | - Ivan Ivić
- Department of Thermophysiology, Institute for Translational Medicine, Medical School, University of Pecs, H-7624 Pecs, Hungary
| | - Eszter Pakai
- Department of Thermophysiology, Institute for Translational Medicine, Medical School, University of Pecs, H-7624 Pecs, Hungary
| | - Kata Fekete
- Department of Thermophysiology, Institute for Translational Medicine, Medical School, University of Pecs, H-7624 Pecs, Hungary
| | - Peter Maroti
- Medical Simulation Education Center, Medical School, University of Pecs, H-7624 Pecs, Hungary
- 3D Printing and Visualization Center, University of Pecs, H-7624 Pecs, Hungary
| | - Roland Told
- Medical Simulation Education Center, Medical School, University of Pecs, H-7624 Pecs, Hungary
- 3D Printing and Visualization Center, University of Pecs, H-7624 Pecs, Hungary
| | - Zoltan Ujfalusi
- Department of Biophysics, Medical School, University of Pecs, H-7624 Pecs, Hungary
| | - Andras Garami
- Department of Thermophysiology, Institute for Translational Medicine, Medical School, University of Pecs, H-7624 Pecs, Hungary
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32
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Kalinke C, de Oliveira PR, Neumsteir NV, Henriques BF, de Oliveira Aparecido G, Loureiro HC, Janegitz BC, Bonacin JA. Influence of filament aging and conductive additive in 3D printed sensors. Anal Chim Acta 2022; 1191:339228. [PMID: 35033250 DOI: 10.1016/j.aca.2021.339228] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 10/18/2021] [Accepted: 10/27/2021] [Indexed: 11/26/2022]
Abstract
3D printing technology combined with electrochemical techniques have allowed the development of versatile and low-cost devices. However, some aspects need to be considered for the good quality and useful life of the sensors. In this work, we have demonstrated herein that the filament aging, the conductive material, and the activation processes (post-treatments) can influence the surface characteristics and the electrochemical performance of the 3D printed sensors. Commercial filaments and 3D printed sensors were morphologically, thermally, and electrochemically analyzed. The activated graphene-based (Black Magic®) sensor showed the best electrochemical response, compared to the carbon black-filament (Proto-Pasta®). In addition, we have proven that filament aging harms the performance of the sensors since the electrodes produced with three years old filament had a considerably lower intra-days reproducibility. Finally, the activated graphene-based sensor has shown the best performance for the electrochemical detection of bisphenol A, demonstrating the importance of evaluating and control the characteristics and quality of filaments to improve the mechanical, conductive, and electrochemical performance of 3D printed sensors.
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Affiliation(s)
- Cristiane Kalinke
- Institute of Chemistry, University of Campinas (UNICAMP), 13083-859, Campinas, São Paulo, Brazil.
| | - Paulo Roberto de Oliveira
- Department of Nature Science, Mathematics and Education, Federal University of São Carlos (UFSCar), 13600-970, Araras, São Paulo, Brazil
| | | | - Brunna Ferri Henriques
- Department of Nature Science, Mathematics and Education, Federal University of São Carlos (UFSCar), 13600-970, Araras, São Paulo, Brazil
| | | | - Hugo Campos Loureiro
- Institute of Chemistry, University of Campinas (UNICAMP), 13083-859, Campinas, São Paulo, Brazil
| | - Bruno Campos Janegitz
- Department of Nature Science, Mathematics and Education, Federal University of São Carlos (UFSCar), 13600-970, Araras, São Paulo, Brazil
| | - Juliano Alves Bonacin
- Institute of Chemistry, University of Campinas (UNICAMP), 13083-859, Campinas, São Paulo, Brazil.
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Grafted Lactic Acid Oligomers on Lignocellulosic Filler towards Biocomposites. MATERIALS 2022; 15:ma15010314. [PMID: 35009460 PMCID: PMC8745966 DOI: 10.3390/ma15010314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 12/28/2021] [Accepted: 12/28/2021] [Indexed: 11/18/2022]
Abstract
Lactic acid oligomers (OLAs) were in situ synthesized from lactic acid (LAc) and grafted onto chokeberry pomace (CP) particleboards by direct condensation. Biocomposites of poly (lactic acid) (PLA) and modified/unmodified CP particles containing different size fractions were obtained using a mini-extruder. To confirm the results of the grafting process, the FTIR spectra of filler particles were obtained. Performing 1HNMR spectroscopy allowed us to determine the chemical structure of synthesized OLAs. The thermal degradation of modified CP and biocomposites were studied using TGA, and the thermal characteristics of biocomposites were investigated using DSC. In order to analyse the adhesion between filler particles and PLA in biocomposites, SEM images of brittle fracture surfaces were registered. The mechanical properties of biocomposites were studied using a tensile testing machine. FTIR and 1HNMR analysis confirmed the successful grafting process of OLAs. The modified filler particles exhibited a better connection with hydrophobic PLA matrix alongside improved mechanical properties than the biocomposites with unmodified filler particles. Moreover, a DSC analysis of the biocomposites with modified CP showed a reduction in glass temperature on average by 9 °C compared to neat PLA. It confirms the plasticizing effect of grafted and ungrafted OLAs. The results are promising, and can contribute to increasing the use of agri-food lignocellulosic residue in manufacturing biodegradable packaging.
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Morphology and mechanical property of quenched poly(L-lactide)/N,N-dimethylacetamide gels. POLYMER 2022. [DOI: 10.1016/j.polymer.2022.124581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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35
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Ciftci F, Duygulu N, Yilmazer Y, Karavelioğlu Z, Çakır Koç R, Gündüz O, Ustündag CB. Antibacterial and cellular behavior of PLA-based bacitracin and zataria multiflora nanofibers produced by electrospinning method. INT J POLYM MATER PO 2021. [DOI: 10.1080/00914037.2021.2008391] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Fatih Ciftci
- Department of Biomedical Engineering, Fatih Sultan Mehmet Vakif University, Istanbul, Turkey
- Technology Transfer Office, Fatih Sultan Mehmet Vakif University, Istanbul, Turkey
| | - Nilüfer Duygulu
- Department of Metallurgical and Material Engineering, Yildiz Technical University, Istanbul, Turkey
| | - Yasemin Yilmazer
- Department of Molecular Biology and Genetics, Faculty of Engineering and Natural Sciences, Istanbul Sabahattin Zaim University, Istanbul, Turkey
| | | | - Rabia Çakır Koç
- Department of Bioengineering, Yildiz Technical University, Istanbul, Turkey
| | - Oguzhan Gündüz
- Center for Nanotechnology & Biomaterials Application and Research (NBUAM), Marmara University, Istanbul, Turkey
- Department of Metallurgical and Materials Engineering, Marmara University, Istanbul, Turkey
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Effect of core-to-shell flowrate ratio on morphology, crystallinity, mechanical properties and wettability of poly(lactic acid) fibers prepared via modified coaxial electrospinning. POLYMER 2021. [DOI: 10.1016/j.polymer.2021.124378] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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37
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Dimonie D, Mathe S, Iftime MM, Ionita D, Trusca R, Iftimie S. Modulation of the PLLA Morphology through Racemic Nucleation to Reach Functional Properties Required by 3D Printed Durable Applications. MATERIALS (BASEL, SWITZERLAND) 2021; 14:6650. [PMID: 34772174 PMCID: PMC8588124 DOI: 10.3390/ma14216650] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 10/29/2021] [Accepted: 10/31/2021] [Indexed: 11/16/2022]
Abstract
This paper presents an alternative for enhancing the durability of poly (L-lactide) (PLLA) by racemic nucleation following stereo-complexation with a selected poly (D-lactide) (PLDA). The compounds are obtained by melt blending of a PLLA grade, previously designed for 3D printing but with a low heat deflection temperature and impact resistance, with grades of PLDA differing in their molecular weight (Mw), D-lactide content (DS) and concentration. Our method considered how to reveal the racemic nucleation caused by stereo-complexation and its influence on functional properties. The FTIR study we performed showed that, depending on Mw, DS and concentration of the stereo-complexer (PDLA) used, bigger or smaller spectral changes can occur. The stereo-complexation was confirmed by the DSC analysis and, for the selected compound, by the POM, SEM, AFM microscopies, functional property and shapeability as 3D printing filaments. All the obtained results sustain the idea that, if a PLLA with Mw of 4.5 × 104 g·mol-1 is modified with PDLA with a medium Mw of 11.6 × 104 g·mol-1, medium DS of 4% and 1% concentration, a racemic nucleation is possible. It produces a racemic polylactic acid (PDLLA) with improved durability and good shapeability as 3D printing filaments. These results are explicable if the dependence of the intermolecular interactions appears between the PLLA and stereo-complexer PDLA. To enlarge the durable applicability of racemic polylactic acid (PDLLA), future research should identify other parameters controling the PLA stereo-complexing as the intensifying the mobility of the macromolecules, the finding of the optimal recemic cristalization window.
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Affiliation(s)
- Doina Dimonie
- National Institute for Research and Development in Chemistry and Petrochemistry, 202 Splaiul Independentei, 060021 Bucharest, Romania;
| | - Silvia Mathe
- Doctoral School “Applied Chemistry and Materials Science”, Politehnica University of Bucharest, 1-7 Gheorghe Polizu, 011061 Bucharest, Romania
| | - Manuela Maria Iftime
- “Petru Poni” Institute of Macromolecular Chemistry, 41A Grigore Ghica Voda Alley, 700487 Iasi, Romania; (M.M.I.); (D.I.)
| | - Daniela Ionita
- “Petru Poni” Institute of Macromolecular Chemistry, 41A Grigore Ghica Voda Alley, 700487 Iasi, Romania; (M.M.I.); (D.I.)
| | - Roxana Trusca
- Department of Science and Engineering of Oxide Materials and Nanomaterials, Politehnica University of Bucharest, 1-7 Gheorghe Polizu, 011061 Bucharest, Romania;
| | - Sorina Iftimie
- Department of Electricity and Magnetism, Solid-State Physics, and Biophysics, Faculty of Physics, University of Bucharest, 405 Atomistilor, 077125 Magurele, Romania;
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Physical Properties and Non-Isothermal Crystallisation Kinetics of Primary Mechanically Recycled Poly(l-lactic acid) and Poly(3-hydroxybutyrate- co-3-hydroxyvalerate). Polymers (Basel) 2021; 13:polym13193396. [PMID: 34641213 PMCID: PMC8512861 DOI: 10.3390/polym13193396] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 09/24/2021] [Accepted: 09/29/2021] [Indexed: 01/20/2023] Open
Abstract
The physical properties and non-isothermal melt- and cold-crystallisation kinetics of poly (l-lactic acid) (PLLA) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) biobased polymers reprocessed by mechanical milling of moulded specimens and followed injection moulding with up to seven recycling cycles are investigated. Non-isothermal crystallisation kinetics are evaluated by the half-time of crystallisation and a procedure based on the mathematical treatment of DSC cumulative crystallisation curves at their inflection point (Kratochvil-Kelnar method). Thermomechanical recycling of PLLA raised structural changes that resulted in an increase in melt flow properties by up to six times, a decrease in the thermal stability by up to 80 °C, a reduction in the melt half-time crystallisation by up to about 40%, an increase in the melt crystallisation start temperature, and an increase in the maximum melt crystallisation rate (up to 2.7 times). Furthermore, reprocessing after the first recycling cycle caused the elimination of cold crystallisation when cooling at a slow rate. These structural changes also lowered the cold crystallisation temperature without impacting the maximum cold crystallisation rate. The structural changes of reprocessed PHBV had no significant effect on the non-isothermal crystallisation kinetics of this material. Additionally, the thermomechanical behaviour of reprocessed PHBV indicates that the technological waste of this biopolymer is suitable for recycling as a reusable additive to the virgin polymer matrix. In the case of reprocessed PLLA, on the other hand, a significant decrease in tensile and flexural strength (by 22% and 46%, respectively) was detected, which reflected changes within the biobased polymer structure. Apart from the elastic modulus, all the other thermomechanical properties of PLLA dropped down with an increasing level of recycling.
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Interfacial Compatibilization into PLA/Mg Composites for Improved In Vitro Bioactivity and Stem Cell Adhesion. Molecules 2021; 26:molecules26195944. [PMID: 34641488 PMCID: PMC8512483 DOI: 10.3390/molecules26195944] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 09/21/2021] [Accepted: 09/27/2021] [Indexed: 01/22/2023] Open
Abstract
The present work highlights the crucial role of the interfacial compatibilization on the design of polylactic acid (PLA)/Magnesium (Mg) composites for bone regeneration applications. In this regard, an amphiphilic poly(ethylene oxide-b-L,L-lactide) diblock copolymer with predefined composition was synthesised and used as a new interface to provide physical interactions between the metallic filler and the biopolymer matrix. This strategy allowed (i) overcoming the PLA/Mg interfacial adhesion weakness and (ii) modulating the composite hydrophilicity, bioactivity and biological behaviour. First, a full study of the influence of the copolymer incorporation on the morphological, wettability, thermal, thermo-mechanical and mechanical properties of PLA/Mg was investigated. Subsequently, the bioactivity was assessed during an in vitro degradation in simulated body fluid (SBF). Finally, biological studies with stem cells were carried out. The results showed an increase of the interfacial adhesion by the formation of a new interphase between the hydrophobic PLA matrix and the hydrophilic Mg filler. This interface stabilization was confirmed by a decrease in the damping factor (tanδ) following the copolymer addition. The latter also proves the beneficial effect of the composite hydrophilicity by selective surface localization of the hydrophilic PEO leading to a significant increase in the protein adsorption. Furthermore, hydroxyapatite was formed in bulk after 8 weeks of immersion in the SBF, suggesting that the bioactivity will be noticeably improved by the addition of the diblock copolymer. This ceramic could react as a natural bonding junction between the designed implant and the fractured bone during osteoregeneration. On the other hand, a slight decrease of the composite mechanical performances was noted.
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Ahmed J, Mulla MZ, Vahora A, Bher A, Auras R. Morphological, barrier and thermo-mechanical properties of high-pressure treated polylactide graphene oxide reinforced composite films. Food Packag Shelf Life 2021. [DOI: 10.1016/j.fpsl.2021.100702] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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41
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Karimi-Avargani M, Bazooyar F, Biria D, Zamani A, Skrifvars M. The promiscuous potential of cellulase in degradation of polylactic acid and its jute composite. CHEMOSPHERE 2021; 278:130443. [PMID: 33836399 DOI: 10.1016/j.chemosphere.2021.130443] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 01/10/2021] [Accepted: 03/27/2021] [Indexed: 06/12/2023]
Abstract
It has been suggested that cellulolytic enzymes can be effective on the degradation of PLA samples. The idea was investigated by examining the impact of cellulase on degradation of PLA and PLA-jute (64/36) composite in an aqueous medium. The obtained results demonstrated 55% and 61% thickness reduction in PLA and PLA-jute specimens after four months of treatment, respectively. Gel permeation chromatography (GPC) showed significant decline in the number average molecular weight (Mn) approximately equal to 85% and 80% for PLA and PLA-jute in comparison with their control. The poly dispersity index (PDI) of PLA and PLA-jute declined 41% and 49% that disclosed more homogenous distribution in molecular weight of the polymer after treatment with cellulase. The cellulase promiscuity effect on PLA degradation was further revealed by Fourier-transform infrared spectroscopy (FT-IR) analysis where substantial decrease in the peak intensities of the polymer related functional groups were observed. In addition, PLA biodegradation was studied in more detail by differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA) of control and cellulase treated specimens. The obtained results confirmed the promiscuous function of cellulase in the presence or the absence of jute as the specific substrate of cellulase. This can be considered as a major breakthrough to develop effective biodegradation processes for PLA products at the end of their life cycle.
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Affiliation(s)
- Mina Karimi-Avargani
- Department of Biotechnology, University of Isfahan, Isfahan, Iran; Swedish Centre for Resource Recovery, University of Borås, Borås, Sweden
| | - Faranak Bazooyar
- Swedish Centre for Resource Recovery, University of Borås, Borås, Sweden
| | - Davoud Biria
- Department of Biotechnology, University of Isfahan, Isfahan, Iran.
| | - Akram Zamani
- Swedish Centre for Resource Recovery, University of Borås, Borås, Sweden
| | - Mikael Skrifvars
- Swedish Centre for Resource Recovery, University of Borås, Borås, Sweden
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42
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Sweeney J, Spencer P, Thompson G, Barker D, Coates P. Constitutive Modelling of Polylactic Acid at Large Deformation Using Multiaxial Strains. Polymers (Basel) 2021; 13:polym13172967. [PMID: 34503007 PMCID: PMC8434546 DOI: 10.3390/polym13172967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 08/26/2021] [Accepted: 08/27/2021] [Indexed: 11/16/2022] Open
Abstract
Sheet specimens of a PLLA-based polymer have been extended at a temperature near to the glass transition in both uniaxial and planar tension, with stress relaxation observed for some time after reaching the final strain. Both axial and transverse stresses were recorded in the planar experiments. In all cases during loading, yielding at small strain was followed by a drop in true stress and then strain hardening. This was followed by stress relaxation at constant strain, during which stress dropped to reach an effectively constant level. Stresses were modelled as steady state and transient components. Steady-state components were identified with the long-term stress in stress relaxation and associated with an elastic component of the model. Transient stresses were modelled using Eyring mechanisms. The greater part of the stress during strain hardening was associated with dissipative Eyring processes. The model was successful in predicting stresses in both uniaxial and planar extension over a limited range of strain rate.
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43
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Przybysz-Romatowska M, Barczewski M, Mania S, Tercjak A, Haponiuk J, Formela K. Morphology, Thermo-Mechanical Properties and Biodegradibility of PCL/PLA Blends Reactively Compatibilized by Different Organic Peroxides. MATERIALS 2021; 14:ma14154205. [PMID: 34361398 PMCID: PMC8347303 DOI: 10.3390/ma14154205] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Revised: 07/23/2021] [Accepted: 07/26/2021] [Indexed: 11/16/2022]
Abstract
Reactive blending is a promising approach for the sustainable development of bio-based polymer blends and composites, which currently is gaining more and more attention. In this paper, biodegradable blends based on poly(ε-caprolactone) (PCL) and poly(lactic acid) (PLA) were prepared via reactive blending performed in an internal mixer. The PCL and PLA content varied in a ratio of 70/30 and 55/45. Reactive modification of PCL/PLA via liquid organic peroxides (OP) including 0.5 wt.% of tert-butyl cumyl peroxide (BU), 2,5-dimethyl-2,5-di-(tert-butylperoxy)-hexane (HX), and tert-butyl peroxybenzoate (PB) is reported. The materials were characterized by rotational rheometer, atomic force microscopy (AFM), thermogravimetry (TGA), differential scanning calorimetry (DSC), tensile tests and biodegradability tests. It was found that the application of peroxides improves the miscibility between PCL and PLA resulted in enhanced mechanical properties and more uniform morphology. Moreover, it was observed that the biodegradation rate of PCL/PLA blends reactively compatibilized was lower comparing to unmodified samples and strongly dependent on the blend ratio and peroxide structure. The presented results confirmed that reactive blending supported by organic peroxide is a promising approach for tailoring novel biodegradable polymeric systems with controllable biodegradation rates.
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Affiliation(s)
- Marta Przybysz-Romatowska
- Department of Polymer Technology, Faculty of Chemistry, Gdańsk University of Technology, Gabriela Narutowicza 11/12, 80-233 Gdańsk, Poland;
- Correspondence: (M.P.-R.); (K.F.)
| | - Mateusz Barczewski
- Institute of Materials Technology, Poznan University of Technology, Piotrowo 3, 61-138 Poznan, Poland;
| | - Szymon Mania
- Department of Chemistry, Technology and Biochemistry of Food, Faculty of Chemistry, Gabriela Narutowicza 11/12, 80-233 Gdańsk, Poland;
| | - Agnieszka Tercjak
- Group ‘Materials + Technologies’ (GMT), Department of Chemical and Environmental Engineering, Faculty of Engineering, University of the Basque Country (UPV/EHU), Pza Europa 1, 20018 Donostia-San Sebastian, Gipuzkoa, Spain;
| | - Józef Haponiuk
- Department of Polymer Technology, Faculty of Chemistry, Gdańsk University of Technology, Gabriela Narutowicza 11/12, 80-233 Gdańsk, Poland;
| | - Krzysztof Formela
- Department of Polymer Technology, Faculty of Chemistry, Gdańsk University of Technology, Gabriela Narutowicza 11/12, 80-233 Gdańsk, Poland;
- Correspondence: (M.P.-R.); (K.F.)
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Kiatiporntipthak K, Thajai N, Kanthiya T, Rachtanapun P, Leksawasdi N, Phimolsiripol Y, Rohindra D, Ruksiriwanich W, Sommano SR, Jantanasakulwong K. Reaction Mechanism and Mechanical Property Improvement of Poly(Lactic Acid) Reactive Blending with Epoxy Resin. Polymers (Basel) 2021; 13:2429. [PMID: 34372029 PMCID: PMC8347510 DOI: 10.3390/polym13152429] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2021] [Revised: 07/18/2021] [Accepted: 07/18/2021] [Indexed: 01/04/2023] Open
Abstract
Polylactic acid (PLA) was melt-blended with epoxy resin to study the effects of the reaction on the mechanical and thermal properties of the PLA. The addition of 0.5% (wt/wt) epoxy to PLA increased the maximum tensile strength of PLA (57.5 MPa) to 67 MPa, whereas the 20% epoxy improved the elongation at break to 12%, due to crosslinking caused by the epoxy reaction. The morphology of the PLA/epoxy blends showed epoxy nanoparticle dispersion in the PLA matrix that presented a smooth fracture surface with a high epoxy content. The glass transition temperature of PLA decreased with an increasing epoxy content owing to the partial miscibility between PLA and the epoxy resin. The Vicat softening temperature of the PLA was 59 °C and increased to 64.6 °C for 0.5% epoxy. NMR confirmed the reaction between the -COOH groups of PLA and the epoxy groups of the epoxy resin. This reaction, and partial miscibility of the PLA/epoxy blend, improved the interfacial crosslinking, morphology, thermal properties, and mechanical properties of the blends.
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Affiliation(s)
- Krittameth Kiatiporntipthak
- Faculty of Agro-Industry, Chiang Mai University, Mae-Hea, Mueang, Chiang Mai 50100, Thailand; (K.K.); (T.K.); (P.R.); (N.L.); (Y.P.)
| | - Nanthicha Thajai
- Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand;
| | - Thidarat Kanthiya
- Faculty of Agro-Industry, Chiang Mai University, Mae-Hea, Mueang, Chiang Mai 50100, Thailand; (K.K.); (T.K.); (P.R.); (N.L.); (Y.P.)
| | - Pornchai Rachtanapun
- Faculty of Agro-Industry, Chiang Mai University, Mae-Hea, Mueang, Chiang Mai 50100, Thailand; (K.K.); (T.K.); (P.R.); (N.L.); (Y.P.)
- Cluster of Agro Bio-Circular-Green Industry, Chiang Mai University, Chiang Mai 50100, Thailand
- Center of Excellence in Materials Science and Technology, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand; (W.R.); (S.R.S.)
| | - Noppol Leksawasdi
- Faculty of Agro-Industry, Chiang Mai University, Mae-Hea, Mueang, Chiang Mai 50100, Thailand; (K.K.); (T.K.); (P.R.); (N.L.); (Y.P.)
- Cluster of Agro Bio-Circular-Green Industry, Chiang Mai University, Chiang Mai 50100, Thailand
- Center of Excellence in Materials Science and Technology, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand; (W.R.); (S.R.S.)
| | - Yuthana Phimolsiripol
- Faculty of Agro-Industry, Chiang Mai University, Mae-Hea, Mueang, Chiang Mai 50100, Thailand; (K.K.); (T.K.); (P.R.); (N.L.); (Y.P.)
- Cluster of Agro Bio-Circular-Green Industry, Chiang Mai University, Chiang Mai 50100, Thailand
- Center of Excellence in Materials Science and Technology, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand; (W.R.); (S.R.S.)
| | - David Rohindra
- School of Biological and Chemical Sciences, Faculty of Science, Technology and Environment, The University of the South Pacific, Laucala Bay Road, Suva, Fiji;
| | - Warintorn Ruksiriwanich
- Center of Excellence in Materials Science and Technology, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand; (W.R.); (S.R.S.)
- Department of Pharmaceutical Sciences, Faculty of Pharmacy, Chiang Mai University, Mae-Hia, Muang, Chiang Mai 50100, Thailand
| | - Sarana Rose Sommano
- Center of Excellence in Materials Science and Technology, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand; (W.R.); (S.R.S.)
- Plant Bioactive Compound Laboratory (BAC), Department of Plant and Soil Sciences, Faculty of Agriculture, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Kittisak Jantanasakulwong
- Faculty of Agro-Industry, Chiang Mai University, Mae-Hea, Mueang, Chiang Mai 50100, Thailand; (K.K.); (T.K.); (P.R.); (N.L.); (Y.P.)
- Cluster of Agro Bio-Circular-Green Industry, Chiang Mai University, Chiang Mai 50100, Thailand
- Center of Excellence in Materials Science and Technology, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand; (W.R.); (S.R.S.)
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Vishnu Chandar J, Mutharasu D, Mohamed K, Marsilla KIK, Shanmugan S, Azlan AA. Synergetic effect of micro-hBN and nano-Al2O3 fillers on structural, surface, thermal, and mechanical properties of PLA/hBN/Al 2O 3 hybrid composites: experimental and theoretical investigation. POLYM-PLAST TECH MAT 2021. [DOI: 10.1080/25740881.2020.1861290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- J. Vishnu Chandar
- School of Mechanical Engineering, Universiti Sains Malaysia (USM), Nibong Tebal, Malaysia
| | - D. Mutharasu
- Western Digital Corporation, MCoE, PTDI-SSD, Western Digital Corporation, Seberang Perai Selatan, Malaysia
| | - K. Mohamed
- School of Mechanical Engineering, Universiti Sains Malaysia (USM), Nibong Tebal, Malaysia
| | - K. I. K. Marsilla
- School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia (USM), Nibong Tebal, Malaysia
| | - S. Shanmugan
- School of Physics, Universiti Sains Malaysia (USM), Minden, Malaysia
| | - A. A. Azlan
- School of Physics, Universiti Sains Malaysia (USM), Minden, Malaysia
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46
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Venkatesh C, Chen Y, Cao Z, Brennan S, Major I, Lyons JG, Devine DM. Influence of extrusion screw speed on the properties of halloysite nanotube impregnated polylactic acid nanocomposites. JOURNAL OF POLYMER ENGINEERING 2021. [DOI: 10.1515/polyeng-2020-0228] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Abstract
Poly (lactic acid)/halloysite nanotube (PLA/HNT) nanocomposites have been studied extensively over the past few years owing to the interesting properties of the polymer, PLA, and the nanoclay, HNT, individually and as composites. In this paper, the influence of the screw speed during extrusion was investigated and was found to have a significant impact on the mechanical and thermal performance of the extruded PLA/HNT nanocomposites. To determine the effect of screw speed on PLA/HNT nanocomposites, 5 and 10 wt% of HNTs were blended into the PLA matrix through compounding at screw speeds of 40, 80, and 140 rpm. Virgin PLA was compounded for comparison. The resultant polymer melt was quench cooled onto a calendar system to produce composite films which were assessed for mechanical, thermal, chemical, and surface properties. Results illustrate that in comparison to 40 and 80 rpm, the virgin PLA when compounded at 140 rpm, indicated a significant increase in the mechanical properties. The PLA/HNT 5 wt% nanocomposite compounded at 140 rpm showed significant improvement in the dispersion of HNTs in the PLA matrix which in turn enhanced the mechanical and thermal properties. This can be attributed to the increased melt shear at higher screw speeds.
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Affiliation(s)
- Chaitra Venkatesh
- Materials Research Institute, Athlone Institute of Technology , Dublin Road , Athlone , Co. Westmeath , Ireland
| | - Yuanyuan Chen
- Materials Research Institute, Athlone Institute of Technology , Dublin Road , Athlone , Co. Westmeath , Ireland
| | - Zhi Cao
- Materials Research Institute, Athlone Institute of Technology , Dublin Road , Athlone , Co. Westmeath , Ireland
| | - Shane Brennan
- Materials Research Institute, Athlone Institute of Technology , Dublin Road , Athlone , Co. Westmeath , Ireland
| | - Ian Major
- Materials Research Institute, Athlone Institute of Technology , Dublin Road , Athlone , Co. Westmeath , Ireland
| | - John G. Lyons
- Faculty of Engineering and Informatics , Athlone Institute of Technology , Dublin Road , Athlone , Co. Westmeath , Ireland
| | - Declan M. Devine
- Materials Research Institute, Athlone Institute of Technology , Dublin Road , Athlone , Co. Westmeath , Ireland
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47
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Malayarom P, Somboonphong N, Pattamaprom C. Simultaneous improvement of impact strength and thermal resistance of PLA/PDLA stereocomplex with core-shell rubber blends. INTERNATIONAL JOURNAL OF POLYMER ANALYSIS AND CHARACTERIZATION 2021. [DOI: 10.1080/1023666x.2021.1887625] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Pongsakorn Malayarom
- Department of Chemical Engineering, Faculty of Engineering, Thammasat University, Pathumthani, Thailand
| | - Nilobol Somboonphong
- Department of Chemical Engineering, Faculty of Engineering, Thammasat University, Pathumthani, Thailand
| | - Cattaleeya Pattamaprom
- Department of Chemical Engineering, Faculty of Engineering, Thammasat University, Pathumthani, Thailand
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48
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Inducing polymer waste biodegradation using oxo-prodegradant and thermoplastic starch based additives. JOURNAL OF POLYMER RESEARCH 2021. [DOI: 10.1007/s10965-021-02457-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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49
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Brounstein Z, Yeager CM, Labouriau A. Development of Antimicrobial PLA Composites for Fused Filament Fabrication. Polymers (Basel) 2021; 13:polym13040580. [PMID: 33671918 PMCID: PMC7918987 DOI: 10.3390/polym13040580] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 02/09/2021] [Accepted: 02/10/2021] [Indexed: 12/31/2022] Open
Abstract
In addition to possessing the desirable properties of being a biodegradable and biocompatible polymer fabricated from renewable resources, poly (lactic acid) (PLA) has useful mechanical and thermal attributes that has enabled it to be one of the most widely-used plastics for medicine, manufacturing, and agriculture. Yet, PLA composites have not been heavily explored for use in 3D-printing applications, and the range of feasible materials for the technology is limited, which inhibits its potential growth and industry adoption. In this study, tunable, multifunctional antimicrobial PLA composite filaments for 3D-printing have been fabricated and tested via chemical, thermal, mechanical, and antimicrobial experiments. Thermally stable antimicrobial ceramics, ZnO and TiO2, were used as fillers up to 30 wt%, and poly (ethylene glycol) (PEG) was used as a plasticizer to tune the physical material properties. Results demonstrate that the PLA composite filaments exhibit the thermal phase behaviors and thermal stability suitable for 3D-printing. Additionally, PEG can be used to tune the mechanical properties while not affecting the antimicrobial efficacy that ZnO and TiO2 imbue.
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Affiliation(s)
- Zachary Brounstein
- Los Alamos National Laboratory, Los Alamos, NM 87545, USA; (Z.B.); (C.M.Y.)
- Department of Nanoscience and Microsystems Engineering, University of New Mexico, Albuquerque, NM 87131, USA
| | - Chris M. Yeager
- Los Alamos National Laboratory, Los Alamos, NM 87545, USA; (Z.B.); (C.M.Y.)
| | - Andrea Labouriau
- Los Alamos National Laboratory, Los Alamos, NM 87545, USA; (Z.B.); (C.M.Y.)
- Correspondence:
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50
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Mathe S, Dimonie D, Cristea M. Thermal analysis and polarized light microscopy as methods to study the increasing of the durability of PLA designed for 3D printing. INTERNATIONAL JOURNAL OF POLYMER ANALYSIS AND CHARACTERIZATION 2021. [DOI: 10.1080/1023666x.2021.1880111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Silvia Mathe
- Doctoral School of Applied Chemistry and Materials Science, Politehnica University of Bucharest, Bucharest, Romania
| | - Doina Dimonie
- National Institute of Research and Development in Chemistry and Petrochemistry, Bucharest, Romania
| | - Mariana Cristea
- Institute of Macromolecular Chemistry “Petru Poni”, Iasi, Romania
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