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Makri SP, Klonos PA, Marra G, Karathanasis AZ, Deligkiozi I, Valera MÁ, Mangas A, Nikolaidis N, Terzopoulou Z, Kyritsis A, Bikiaris DN. Structure-property relationships in renewable composites of poly(lactic acid) reinforced by low amounts of micro- and nano-kraft-lignin. SOFT MATTER 2024. [PMID: 38885039 DOI: 10.1039/d4sm00622d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/20/2024]
Abstract
We investigate the direct and indirect effects of micro- and nano-kraft lignin, kL and NkL, respectively, at a quite low amount of 0.5 wt%, in poly(lactic acid) (PLA)-based composites. These renewable composites were prepared via two routes, either simple melt compounding or in situ reactive extrusion. The materials are selected and prepared using targeted methods in order to vary two variables, i.e., the size of kL and the synthetic method, while maintaining constant polymer chain lengths, L-/D-lactide isomer ratio and filler amounts. The direct/indirect effects were respectively investigated in the amorphous/semicrystalline state, as crystallinity plays in general a dominant role in polymers. The investigation involves structural, thermal and molecular mobility aspects. Non-extensive polymer-lignin interactions were recorded here, whereas the presence of the fillers led to both enhancements and suppressions of properties, e.g., glass transition, crystallization, melting temperatures, etc. The local and segmental molecular dynamics map of the said systems was constructed and is shown here for the first time, demonstrating both expected and unexpected trends. An interesting discrepancy between the trends in the calorimetric measurement against the dielectric Tg is revealed, providing indications for 'dynamical heterogeneities' in the composites as compared to neat PLA. The reactive extrusion as compared to compounding-based systems was found to exhibit stronger effects on crystallizability and mobility, most, probably due to the severe enhancement of the chains' diffusion. In general, the effects are more pronounced when employing nano-lignin compared to micro-lignin, which is the expected beneficial behaviour of nanocomposites vs. conventional composites. Interestingly, the variety of these effects can be easily manipulated by the proper selection of the preparation method and/or the thermal treatment under relatively mild conditions. The latter capability is actually desirable for processing and targeted applications and is proved here, once again, as an advantage of biobased polyesters such as PLA.
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Affiliation(s)
- Sofia P Makri
- Laboratory of Polymer Chemistry and Technology, Department of Chemistry, Aristotle University of Thessaloniki, GR-541 24, Thessaloniki, Greece.
- Creative Nano PC, 43 Tatoiou, Metamorfosi, 14451 Athens, Greece
| | - Panagiotis A Klonos
- Laboratory of Polymer Chemistry and Technology, Department of Chemistry, Aristotle University of Thessaloniki, GR-541 24, Thessaloniki, Greece.
- Dielectrics Group, Department of Physics, National Technical University of Athens, Zografou Campus, 15780, Athens, Greece
| | - Giacomo Marra
- AIMPLAS, Asociación de Investigación de Materiales Plásticos Y Conexas, Mechanochemistry & Reactive Extrusion, Carrer de Gustave Eiffel, 4, 46980 Valencia, Spain
| | | | | | - Miguel Ángel Valera
- AIMPLAS, Asociación de Investigación de Materiales Plásticos Y Conexas, Mechanochemistry & Reactive Extrusion, Carrer de Gustave Eiffel, 4, 46980 Valencia, Spain
| | - Ana Mangas
- AIMPLAS, Asociación de Investigación de Materiales Plásticos Y Conexas, Mechanochemistry & Reactive Extrusion, Carrer de Gustave Eiffel, 4, 46980 Valencia, Spain
| | - Nikolaos Nikolaidis
- Laboratory of Polymer Chemistry and Technology, Department of Chemistry, Aristotle University of Thessaloniki, GR-541 24, Thessaloniki, Greece.
| | - Zoi Terzopoulou
- Laboratory of Polymer Chemistry and Technology, Department of Chemistry, Aristotle University of Thessaloniki, GR-541 24, Thessaloniki, Greece.
| | - Apostolos Kyritsis
- Dielectrics Group, Department of Physics, National Technical University of Athens, Zografou Campus, 15780, Athens, Greece
| | - Dimitrios N Bikiaris
- Laboratory of Polymer Chemistry and Technology, Department of Chemistry, Aristotle University of Thessaloniki, GR-541 24, Thessaloniki, Greece.
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Klonos PA, Bikiaris ND, Zamboulis A, Valera MÁ, Mangas A, Kyritsis A, Terzopoulou Z. Segmental mobility in sustainable copolymers based on poly(lactic acid) blocks built onto poly(butylene succinate) in situ. SOFT MATTER 2023; 19:7846-7858. [PMID: 37811662 DOI: 10.1039/d3sm00980g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/10/2023]
Abstract
Two series of newly synthesized sustainable block copolymers based on poly(butylene succinate) (PBSu) and polylactide (PLA) were studied. The copolymers were synthesized by a ring-opening polymerization of PLA in the presence of two initial PBSu of low molar mass. We focused on the effects of the PBSu/PLA ratio (1/99 up to 15/85), chain length and initial PBSu length on the final thermal transitions in the copolymers with an emphasis on molecular mobility/dynamics and subsequently on crystallization. Both aspects are considered relevant to the final materials performance, as well as facilitation of polymer renewability. Calorimetry and dielectric spectroscopy were the main investigation tools. In the amorphous state (i.e., in which the direct effects of copolymer structure are assessable), the segmental mobility of neat PLA was significantly faster in the copolymers. Segmental mobility was monitored via the decrease in the calorimetric and dielectric (α relaxation) glass-transition temperatures, Tg and Tg,diel, respectively. The effect was systematic with an increase in the PBSu/PLA ratio, and was rationalized through the plasticizing role of PBSu (low-Tg component) and facilitated also by the simultaneous lowering of the chain length in the copolymers. Dielectric spectroscopy allowed evaluation of the dynamical fragility (cooperativity) of chains, which was strongly suppressed in the copolymers. This finding suggested an increase in free volume or a gradual increase of interchain distances. This phenomenon could favor the natural enzymatic degradation of the systems (compostability), which is limited in neat PLA. We recorded enhancement of nucleation and the crystalline fraction in the copolymers that was likely connected with faster chain diffusion. Further lowering of the Tg with the implementation of crystallization was noted (which seemed a controversial effect) but which indicated crystallization-induced phase separation.
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Affiliation(s)
- Panagiotis A Klonos
- Department of Chemistry, Laboratory of Polymer Chemistry and Technology, Aristotle University of Thessaloniki, GR-541 24, Thessaloniki, Greece.
- Department of Physics, National Technical University of Athens, Zografou Campus, 15780, Athens, Greece
| | - Nikolaos D Bikiaris
- Department of Chemistry, Laboratory of Polymer Chemistry and Technology, Aristotle University of Thessaloniki, GR-541 24, Thessaloniki, Greece.
| | - Alexandra Zamboulis
- Department of Chemistry, Laboratory of Polymer Chemistry and Technology, Aristotle University of Thessaloniki, GR-541 24, Thessaloniki, Greece.
| | - Miguel Ángel Valera
- AIMPLAS, Asociación de Investigación de Materiales Plásticos Y Conexas, Carrer de Gustave Eiffel, 4, 46980 Paterna, Valencia, Spain
| | - Ana Mangas
- AIMPLAS, Asociación de Investigación de Materiales Plásticos Y Conexas, Carrer de Gustave Eiffel, 4, 46980 Paterna, Valencia, Spain
| | - Apostolos Kyritsis
- Department of Physics, National Technical University of Athens, Zografou Campus, 15780, Athens, Greece
| | - Zoi Terzopoulou
- Department of Chemistry, Laboratory of Polymer Chemistry and Technology, Aristotle University of Thessaloniki, GR-541 24, Thessaloniki, Greece.
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Hu B, Wang L, Zeng J, Ge Y, Pan S, Shao Y, Lu H. Straightforward Strategy Toward In Situ Water-Phase Exfoliation and Improved Interfacial Adhesion to Fabricate High-Performance Polypropylene/Graphene Nanocomposites. ACS APPLIED MATERIALS & INTERFACES 2023; 15:37903-37915. [PMID: 37493641 DOI: 10.1021/acsami.3c06185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/27/2023]
Abstract
Graphene is a potential candidate for achieving high-performance and multifunctional polypropylene (PP) composites. However, the complex manufacturing process and low dispersibility of graphene, as well as poor interfacial adhesion between graphene and polypropylene chains, stifle progress on large-scale production and applications of graphene/polypropylene composites. Here, we develop a strategy of maleic anhydride grafted polypropylene (MAPP) latex-assisted graphene exfoliation and melt blending to address the key challenges facing in industrial production. The surface property of the graphitic precursor is well-designed to achieve a high graphene exfoliation yield of ∼100% and induce abundant hydrogen bonding between the obtained mild-oxidized graphene (MOG) sheets and MAPP chains. Therefore, the MAPP-modified MOG can homogeneously disperse in the PP matrix and exhibits an excellent interfacial compatibility with the polymer. The addition of 5 wt % MOG results in simultaneous increase in the initial decomposition temperature, crystallization temperature, tensile strength, and Young's modulus by 43.2, 11.4 °C, 21.5, and 50.7%, respectively, and the electrical conductivity increases to 0.02 S·m-1. This work illustrates a practical solution to low-cost, eco-friendly, and feasible industrial production of graphene/PP composites through synchronous exfoliation and interfacial modification of graphene.
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Affiliation(s)
- Bo Hu
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Collaborative Innovation Center of Polymers and Polymer Composites, Fudan University, 2005 Songhu Road, Shanghai 200438, China
| | - Lequan Wang
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Collaborative Innovation Center of Polymers and Polymer Composites, Fudan University, 2005 Songhu Road, Shanghai 200438, China
| | - Jiaxi Zeng
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Collaborative Innovation Center of Polymers and Polymer Composites, Fudan University, 2005 Songhu Road, Shanghai 200438, China
| | - Yuanhang Ge
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Collaborative Innovation Center of Polymers and Polymer Composites, Fudan University, 2005 Songhu Road, Shanghai 200438, China
| | - Shaoxue Pan
- Engineering Research Institute, China Construction Eighth Engineering Division Corp., Ltd., 1568 Century Avenue, Shanghai 200122, China
| | - Yizhen Shao
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Collaborative Innovation Center of Polymers and Polymer Composites, Fudan University, 2005 Songhu Road, Shanghai 200438, China
| | - Hongbin Lu
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Collaborative Innovation Center of Polymers and Polymer Composites, Fudan University, 2005 Songhu Road, Shanghai 200438, China
- Yiwu Research Institute of Fudan University, Chengbei Road, Yiwu, Zhejiang 322000, China
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Organo-modified nanoclays induce changes in the physical properties of polyamide 66. Polym Bull (Berl) 2023. [DOI: 10.1007/s00289-023-04675-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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Makri SP, Xanthopoulou E, Klonos PA, Grigoropoulos A, Kyritsis A, Tsachouridis K, Anastasiou A, Deligkiozi I, Nikolaidis N, Bikiaris DN. Effect of Micro- and Nano-Lignin on the Thermal, Mechanical, and Antioxidant Properties of Biobased PLA-Lignin Composite Films. Polymers (Basel) 2022; 14:polym14235274. [PMID: 36501671 PMCID: PMC9737150 DOI: 10.3390/polym14235274] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 11/24/2022] [Accepted: 11/28/2022] [Indexed: 12/07/2022] Open
Abstract
Bio-based poly(lactic acid) (PLA) composite films were produced using unmodified soda micro- or nano-lignin as a green filler at four different contents, between 0.5 wt% and 5 wt%. The PLA-lignin composite polymers were synthesized by solvent casting to prepare a masterbatch, followed by melt mixing. The composites were then converted into films, to evaluate the effect of lignin content and size on their physicochemical and mechanical properties. Differential scanning calorimetry (DSC), supported by polarized light microscopy (PLM), infrared spectroscopy (FTIR-ATR), X-ray diffraction (XRD), and transmission electron microscopy (TEM) were employed to investigate the PLA crystallization and the interactions with Lignin (L) and Nanolignin (NL). The presence of both fillers (L and NL) had a negligible effect on the glass transition temperature (chain diffusion). However, it resulted in suppression of the corresponding change in heat capacity. This was indicative of a partial immobilization of the PLA chains on the lignin entities, due to interfacial interactions, which was slightly stronger in the case of NL. Lignin was also found to facilitate crystallization, in terms of nucleation; whereas, this was not clear in the crystalline fraction. The addition of L and NL led to systematically larger crystallites compared with neat PLA, which, combined with the higher melting temperature, provided indications of a denser crystal structure in the composites. The mechanical, optical, antioxidant, and surface properties of the composite films were also investigated. The tensile strength and Young's modulus were improved by the addition of L and especially NL. The UV-blocking and antioxidant properties of the composite films were also enhanced, especially at higher filler contents. Importantly, the PLA-NL composite films constantly outperformed their PLA-L counterparts, due to the finer dispersion of NL in the PLA matrix, as verified by the TEM micrographs. These results suggest that bio-based and biodegradable PLA films filled with L, and particularly NL, can be employed as competitive and green alternatives in the food packaging industry.
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Affiliation(s)
- Sofia P. Makri
- Creative Nano PC, 43 Tatoiou, Metamorfosi, 14451 Athens, Greece
- Laboratory of Polymer Chemistry and Technology, Department of Chemistry, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - Eleftheria Xanthopoulou
- Laboratory of Polymer Chemistry and Technology, Department of Chemistry, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - Panagiotis A. Klonos
- Laboratory of Polymer Chemistry and Technology, Department of Chemistry, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
- Department of Physics, National Technical University of Athens (NTUA), Zografou Campus, 15780 Athens, Greece
| | | | - Apostolos Kyritsis
- Department of Physics, National Technical University of Athens (NTUA), Zografou Campus, 15780 Athens, Greece
| | - Konstantinos Tsachouridis
- Department of Chemical Engineering and Analytical Science, University of Manchester, Manchester M1 3AL, UK
| | - Antonios Anastasiou
- Department of Chemical Engineering and Analytical Science, University of Manchester, Manchester M1 3AL, UK
| | | | - Nikolaos Nikolaidis
- Laboratory of Polymer Chemistry and Technology, Department of Chemistry, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
- Correspondence: (N.N.); (D.N.B.)
| | - Dimitrios N. Bikiaris
- Laboratory of Polymer Chemistry and Technology, Department of Chemistry, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
- Correspondence: (N.N.); (D.N.B.)
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Chen Q, Auras R, Corredig M, Kirkensgaard JJK, Mamakhel A, Uysal-Unalan I. New opportunities for sustainable bioplastic development: Tailorable polymorphic and three-phase crystallization of stereocomplex polylactide by layered double hydroxide. Int J Biol Macromol 2022; 222:1101-1109. [PMID: 36174869 DOI: 10.1016/j.ijbiomac.2022.09.205] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 09/20/2022] [Accepted: 09/22/2022] [Indexed: 11/05/2022]
Abstract
Stereocomplexation between enantiomeric poly(l-lactide) (PLLA) and poly(d-lactide) (PDLA) is a promising sustainable approach and gaining momentum to overcome the shortcomings of polylactide (PLA) for its use as a replacement for fossil-based plastics. Filler addition in tailoring the crystallization of stereocomplex PLA (SC-PLA) attracts extensive attention; however, research has primarily focused on the heterogeneous nucleation effect of filler. The impact of filler on the chain behavior of SC-PLA during crystallization has not been exclusively discussed, and the rigid amorphous fraction (RAF) development remains unknown. In this study, the crystallization of PLLA/PDLA blends was modified by low loading of layered double hydroxide (LDH) (≤ 1 wt%) with the proposed local effect of such filler, and additional RAF development was incurred. In the early stage of crystallization, LDH facilitates the pairing of PLLA and PDLA and arrests the ordered SC pairs during the dynamic balance between the separation and pairing of racemic segments. This explains the severely suppressed homochiral (HC) crystallization, promoted SC crystallization, and additional RAF formation driven by the nucleation-induced chain ordering. This work, for the first time, highlights the role of LDH in creating SC-PLA with tailorable polymorphism and RAF, where the mechanism can be extended to other filler-type nucleator systems.
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Affiliation(s)
- Qi Chen
- Department of Food Science, Aarhus University, Agro Food Park 48, 8200 Aarhus N, Denmark; CiFOOD - Center for Innovative Food Research, Aarhus University, Agro Food Park, 48, 8200 Aarhus N, Denmark
| | - Rafael Auras
- School of Packaging, Michigan State University, East Lansing, MI 48824-1223, USA
| | - Milena Corredig
- Department of Food Science, Aarhus University, Agro Food Park 48, 8200 Aarhus N, Denmark; CiFOOD - Center for Innovative Food Research, Aarhus University, Agro Food Park, 48, 8200 Aarhus N, Denmark
| | - Jacob Judas Kain Kirkensgaard
- Department of Food Science, University of Copenhagen, 1958 Frederiksberg C, Denmark; Niels Bohr Institute, University of Copenhagen, 2100 Copenhagen Ø, Denmark
| | - Aref Mamakhel
- Department of Chemistry, Aarhus University, 8000 Aarhus C, Denmark
| | - Ilke Uysal-Unalan
- Department of Food Science, Aarhus University, Agro Food Park 48, 8200 Aarhus N, Denmark; CiFOOD - Center for Innovative Food Research, Aarhus University, Agro Food Park, 48, 8200 Aarhus N, Denmark.
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Klonos PA, Terzopoulou Z, Zamboulis A, Valera MÁ, Mangas A, Kyritsis A, Pissis P, Bikiaris DN. Direct and indirect effects on molecular mobility in renewable polylactide-poly(propylene adipate) block copolymers as studied via dielectric spectroscopy and calorimetry. SOFT MATTER 2022; 18:3725-3737. [PMID: 35503564 DOI: 10.1039/d2sm00261b] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
In this work, we study a series of sustainable block copolymers based on polylactide, PLA, and poly(propylene adipate), PPAd, both polymers being prepared from renewable resources. Envisaging a wide range of future applications in the frame of a green and circular economy, e.g., packaging materials replacing conventional petrochemicals, the employment of PPAd aims at lowering the glass transition and melting temperatures of PLA and, finally, facilitation of the enzymatic degradation and compostability. The copolymers have been synthesized via ring opening polymerization of lactides in the presence of propylene adipate oligomers (5, 15 and 25%). The direct effects on the molecular mobility by the structure/composition are assessed in the amorphous state employing broadband dielectric spectroscopy (BDS) and calorimetry. BDS allowed the recording of local PLA and PPAd dynamics in all cases. The effects on local relaxations suggest favoring of interchain interactions, both PLA-PPAd and PPAd-PPAd. Regarding the more important segmental dynamics, the presence of PPAd leads to faster polymer chain diffusion, as monitored by the significant lowering of the dielectric and calorimetric glass transition temperature, Tg. This suggests the plasticizing role of PPAd on PLA (majority) in combination with the lowering of the average molar mass, Mn, in the copolymers from ∼75 to ∼30 kg mol-1, which is the actual scope for the synthesis of these materials. Interestingly, a strong suppression in fragility (chain cooperativity) is additionally recorded. In contrast to calorimetry and due to the high resolving power of BDS, for the higher PPAd fraction, the weak segmental relaxation of PPAd was additionally recorded. Overall, the recordings suggest a strong increase in free volume and two individual dynamic states, one for 0 and 5% PPAd and another for 15 and 25% PPAd. Within the latter, we gained indications for partial phase nano-separation of PPAd. Regarding indirect effects, these were followed via crystallization. Independent of the method of crystallization, namely, melt or cold, the presence of PPAd led to the systematic lowering of crystallization and melting temperatures and enthalpies. The effects reflect the decrease of crystalline nuclei, which is confirmed by optical microscopy as in the copolymers fewer although larger crystals are formed.
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Affiliation(s)
- Panagiotis A Klonos
- Department of Chemistry, Laboratory of Polymer Chemistry and Technology, Aristotle University of Thessaloniki, GR-541 24, Thessaloniki, Greece.
- Department of Physics, National Technical University of Athens (NTUA), Zografou Campus, 15780, Athens, Greece
| | - Zoi Terzopoulou
- Department of Chemistry, Laboratory of Polymer Chemistry and Technology, Aristotle University of Thessaloniki, GR-541 24, Thessaloniki, Greece.
| | - Alexandra Zamboulis
- Department of Chemistry, Laboratory of Polymer Chemistry and Technology, Aristotle University of Thessaloniki, GR-541 24, Thessaloniki, Greece.
| | - Miguel Ángel Valera
- AIMPLAS, Asociación de Investigación de Materiales Plásticos Y Conexas, Carrer de Gustave Eiffel, 4, 46980 Valencia, Spain
| | - Ana Mangas
- AIMPLAS, Asociación de Investigación de Materiales Plásticos Y Conexas, Carrer de Gustave Eiffel, 4, 46980 Valencia, Spain
| | - Apostolos Kyritsis
- Department of Physics, National Technical University of Athens (NTUA), Zografou Campus, 15780, Athens, Greece
| | - Polycarpos Pissis
- Department of Physics, National Technical University of Athens (NTUA), Zografou Campus, 15780, Athens, Greece
| | - Dimitrios N Bikiaris
- Department of Chemistry, Laboratory of Polymer Chemistry and Technology, Aristotle University of Thessaloniki, GR-541 24, Thessaloniki, Greece.
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Jariyavidyanont K, Du M, Yu Q, Thurn-Albrecht T, Schick C, Androsch R. Bulk enthalpy of melting of poly (l-lactic acid) (PLLA) determined by fast scanning chip calorimetry. Macromol Rapid Commun 2022; 43:e2200148. [PMID: 35343619 DOI: 10.1002/marc.202200148] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 03/19/2022] [Indexed: 11/11/2022]
Abstract
The bulk enthalpy of melting of α-crystals of poly (l-lactic acid) (PLLA) has been evaluated by fast scanning chip calorimetry (FSC), by analysis of the correlation between the measured enthalpy of melting of sets of samples of different crystallinity and the corresponding heat capacity at 90°C, that is at a temperature higher than the glass transition temperature of the bulk amorphous phase and lower than the melting temperature. Extrapolation of this relationship for crystals formed at 140°C towards the heat capacity of fully solid PLLA yields a value of about 104.5±6 J/g when melting occurs at 180-200°C. The analysis is based on the presence of a two-phase structure, that is, absence of a vitrified rigid amorphous fraction (RAF) at the temperature of analysis of the solid fraction of the material (90°C). Formation and vitrification of an RAF was suppressed by avoiding both continuation of primary crystallization and secondary crystallization during cooling the system from the crystallization temperature of 140°C to 90°C, making use of the high cooling capacity of FSC. Small-angle X-ray scattering (SAXS) confirmed distinct thickening of initially grown lamellae which only is possible if these lamellae are not surrounded by a glassy RAF. Linear crystallinity values obtained by SAXS and calorimetrically determined enthalpy-based crystallinities agree close to each other. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Katalee Jariyavidyanont
- Interdisciplinary Center for Transfer-oriented Research in Natural Sciences, Martin Luther University Halle-Wittenberg, Halle/Saale, 06099, Germany
| | - Mengxue Du
- Interdisciplinary Center for Transfer-oriented Research in Natural Sciences, Martin Luther University Halle-Wittenberg, Halle/Saale, 06099, Germany
| | - Qiang Yu
- Institute of Physics, Martin Luther University Halle-Wittenberg, Halle/Saale, 06099, Germany
| | - Thomas Thurn-Albrecht
- Institute of Physics, Martin Luther University Halle-Wittenberg, Halle/Saale, 06099, Germany
| | - Christoph Schick
- University of Rostock, Institute of Physics and Competence Center CALOR, Albert-Einstein-Str. 23-24, Rostock, 18059, Germany.,Butlerov Institute of Chemistry, Kazan Federal University, 18 Kremlyovskaya Street, Kazan, 420008, Russia
| | - René Androsch
- Interdisciplinary Center for Transfer-oriented Research in Natural Sciences, Martin Luther University Halle-Wittenberg, Halle/Saale, 06099, Germany
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Mavronasou K, Zamboulis A, Klonos P, Kyritsis A, Bikiaris DN, Papadakis R, Deligkiozi I. Poly(vinyl pyridine) and Its Quaternized Derivatives: Understanding Their Solvation and Solid State Properties. Polymers (Basel) 2022; 14:polym14040804. [PMID: 35215717 PMCID: PMC8962976 DOI: 10.3390/polym14040804] [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: 01/27/2022] [Revised: 02/15/2022] [Accepted: 02/17/2022] [Indexed: 01/17/2023] Open
Abstract
A series of N-methyl quaternized derivatives of poly(4-vinylpyridine) (PVP) were synthesized in high yields with different degrees of quaternization, obtained by varying the methyl iodide molar ratio and affording products with unexplored optical and solvation properties. The impact of quaternization on the physicochemical properties of the copolymers, and notably the solvation properties, was further studied. The structure of the synthesized polymers and the quaternization degrees were determined by infrared and nuclear magnetic spectroscopies, while their thermal characteristics were studied by differential scanning calorimetry and their thermal stability and degradation by thermogravimetric analysis (TG-DTA). Attention was given to their optical properties, where UV-Vis and diffuse reflectance spectroscopy (DRS) measurements were carried out. The optical band gap of the polymers was calculated and correlated with the degree of quaternization. The study was further orientated towards the solvation properties of the polymers in binary solvent mixtures that strongly depend on the degree of quaternization, enabling a better understanding of the key polymer (solute)-solvent interactions. The assessment of the underlying solvation phenomena was performed in a system of different ratios of DMSO/H2O and the solvatochromic indicator used was Reichardt’s dye. Solvent polarity parameters have a significant effect on the visible spectra of the nitrogen quaternization of PVP studied in this work and a detailed path towards this assessment is presented.
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Affiliation(s)
| | - Alexandra Zamboulis
- Laboratory of Polymer Chemistry and Technology, Department of Chemistry, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece; (A.Z.); (P.K.); (D.N.B.)
| | - Panagiotis Klonos
- Laboratory of Polymer Chemistry and Technology, Department of Chemistry, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece; (A.Z.); (P.K.); (D.N.B.)
- Department of Physics, Zografou Campus, National Technical University of Athens, 15780 Athens, Greece;
| | - Apostolos Kyritsis
- Department of Physics, Zografou Campus, National Technical University of Athens, 15780 Athens, Greece;
| | - Dimitrios N. Bikiaris
- Laboratory of Polymer Chemistry and Technology, Department of Chemistry, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece; (A.Z.); (P.K.); (D.N.B.)
| | | | - Ioanna Deligkiozi
- Creative Nano PC, 4 Leventi Street, Peristeri, 12132 Athens, Greece;
- Correspondence:
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Zhang R, Jariyavidyanont K, Du M, Zhuravlev E, Schick C, Androsch R. Nucleation and crystallization kinetics of polyamide 12 investigated by fast scanning calorimetry. JOURNAL OF POLYMER SCIENCE 2021. [DOI: 10.1002/pol.20210813] [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]
Affiliation(s)
- Rui Zhang
- Interdisciplinary Center for Transfer‐oriented Research in Natural Sciences (IWE TFN) Martin Luther University Halle‐Wittenberg Halle/Saale Germany
| | - Katalee Jariyavidyanont
- Interdisciplinary Center for Transfer‐oriented Research in Natural Sciences (IWE TFN) Martin Luther University Halle‐Wittenberg Halle/Saale Germany
| | - Mengxue Du
- Interdisciplinary Center for Transfer‐oriented Research in Natural Sciences (IWE TFN) Martin Luther University Halle‐Wittenberg Halle/Saale Germany
| | - Evgeny Zhuravlev
- Institute of Physics and Competence Centre CALOR University of Rostock Rostock Germany
| | - Christoph Schick
- Institute of Physics and Competence Centre CALOR University of Rostock Rostock Germany
- Butlerov Institute of Chemistry Kazan Federal University Kazan Russia
| | - René Androsch
- Interdisciplinary Center for Transfer‐oriented Research in Natural Sciences (IWE TFN) Martin Luther University Halle‐Wittenberg Halle/Saale Germany
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11
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Xanthopoulou E, Klonos PA, Zamboulis A, Terzopoulou Z, Kyritsis A, Pissis P, Bikiaris DN, Papageorgiou GZ. Molecular mobility investigation of the biobased Poly(ethylene vanillate) and Poly(propylene vanillate). POLYMER 2021. [DOI: 10.1016/j.polymer.2021.124197] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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12
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Benz J, Bonten C. Rigid Amorphous Fraction as an Indicator for Polymer-Polymer Interactions in Highly Filled Plastics. Polymers (Basel) 2021; 13:polym13193349. [PMID: 34641165 PMCID: PMC8512654 DOI: 10.3390/polym13193349] [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: 06/17/2021] [Revised: 09/27/2021] [Accepted: 09/27/2021] [Indexed: 11/16/2022] Open
Abstract
Above a percolation threshold a flow restriction has to be overcome by higher pressure in plastic processing. Besides amount and geometry of fillers, the interactions of polymer and filler are important. By differing the amorphous phase of polymers into a rigid amorphous and a mobile amorphous fraction, predictions about interactions are possible. The objective is the generation of a flow restriction and the combined investigation of polymer-particle interaction. SiO2 was used up to 50 vol.% in different spherical sizes in PLA and PP. A capillary-rheometer was used as a tool to create a yield point and by that investigations into the state of the flow restriction were possible. All produced compounds showed, in plate-plate rheometry, an increase in viscosity for lower shear rates and a significant change in the storage modulus. In DSC, hardly any specific rigid amorphous fraction was detectable, which suggests that there is a minor interaction between macromolecules and filler. This leads to the conclusion that the change in flow behavior is mainly caused by a direct interaction between the particles, even though they are theoretically too far away from each other. First images in the state of the yield point show a displacement of the particles against each other.
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13
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Albozahid M, Naji HZ, Alobad ZK, Saiani A. TPU nanocomposites tailored by graphene nanoplatelets: the investigation of dispersion approaches and annealing treatment on thermal and mechanical properties. Polym Bull (Berl) 2021. [DOI: 10.1007/s00289-021-03898-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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14
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Rigid amorphous fraction and crystallinity in cold-crystallized syndiotactic polystyrene: Characterization by differential scanning calorimetry. POLYMER 2021. [DOI: 10.1016/j.polymer.2021.124044] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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15
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Righetti MC, Di Lorenzo ML, Cinelli P, Gazzano M. Temperature dependence of the rigid amorphous fraction of poly(butylene succinate). RSC Adv 2021; 11:25731-25737. [PMID: 35478875 PMCID: PMC9036998 DOI: 10.1039/d1ra03775g] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Accepted: 06/16/2021] [Indexed: 11/21/2022] Open
Abstract
In this contribution the temperature evolution of the constrained or rigid amorphous fraction (RAF) of biodegradable and biocompatible poly(butylene succinate) (PBS) was quantified, after detailed thermodynamic characterization by differential scanning calorimetry and X-ray diffraction analysis. At the glass transition temperature, around -40 °C, the rigid amorphous fraction in PBS is about 0.25. It decreases with increasing temperature and becomes zero in proximity of 25 °C. Thus, at room temperature and at the human body temperature, all the amorphous fraction is mobile. This information is important for the development of PBS products for various applications, including biomedical applications, since physical properties of the rigid amorphous fraction, for example mechanical and permeability properties, are different from those of the mobile amorphous fraction.
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Affiliation(s)
- Maria Cristina Righetti
- CNR-IPCF, National Research Council - Institute for Chemical and Physical Processes Via Moruzzi 1 56124 Pisa Italy
| | - Maria Laura Di Lorenzo
- CNR-IPCB, National Research Council - Institute of Polymers, Composites and Biomaterials Via Campi Flegrei 24 80078 Pozzuoli Italy
| | - Patrizia Cinelli
- University of Pisa, Department of Civil and Industrial Engineering Largo Lazzarino 2 56122 Pisa Italy
| | - Massimo Gazzano
- CNR-ISOF, National Research Council - Institute of Organic Synthesis and Photoreactivity Via Gobetti 101 40129 Bologna Italy
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16
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Ramakrishnan V, Goossens JGP, Hoeks TL, Peters GWM. Anomalous Terminal Shear Viscosity Behavior of Polycarbonate Nanocomposites Containing Grafted Nanosilica Particles. NANOMATERIALS (BASEL, SWITZERLAND) 2021; 11:1839. [PMID: 34361225 PMCID: PMC8308399 DOI: 10.3390/nano11071839] [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: 06/04/2021] [Revised: 07/07/2021] [Accepted: 07/09/2021] [Indexed: 11/19/2022]
Abstract
Viscosity controls an important issue in polymer processing. This paper reports on the terminal viscosity behavior of a polymer melt containing grafted nanosilica particles. The melt viscosity behavior of the nanocomposites was found to depend on the interaction between the polymer matrix and the nanoparticle surface. In the case of polycarbonate (PC) nanocomposites, the viscosity decreases by approximately 25% at concentrations below 0.7 vol% of nanosilica, followed by an increase at higher concentrations. Chemical analysis shows that the decrease in viscosity can be attributed to in situ grafting of PC on the nanosilica surface, leading to a lower entanglement density around the nanoparticle. The thickness of the graft layer was found to be of the order of the tube diameter, with the disentangled zone being approximately equal to the radius of gyration (Rg) polymer chain. Furthermore, it is shown that the grafting has an effect on the motion of the PC chains at all timescales. Finally, the viscosity behavior in the PC nanocomposites was found to be independent of the molar mass of PC. The PC data are compared with polystyrene nanocomposites, for which the interaction between the polymer and nanoparticles is absent. The results outlined in this paper can be utilized for applications with low shear processing conditions, e.g., rotomolding, 3D printing, and multilayer co-extrusion.
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Affiliation(s)
- Vaidyanath Ramakrishnan
- Department of Mechanical Engineering, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands;
| | - Johannes G. P. Goossens
- Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands;
| | - Theodorus L. Hoeks
- Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands;
| | - Gerrit W. M. Peters
- Department of Mechanical Engineering, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands;
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17
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Androsch R, Toda A, Furushima Y, Schick C. Insertion‐Crystallization‐Induced Low‐Temperature Annealing Peaks in Melt‐Crystallized Poly(
l
‐Lactic Acid). MACROMOL CHEM PHYS 2021. [DOI: 10.1002/macp.202100177] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- René Androsch
- Interdisciplinary Center for Transfer‐oriented Research in Natural Sciences Martin Luther University Halle‐Wittenberg Saale Halle 06099 Germany
| | - Akihiko Toda
- Graduate School of Advanced Science and Engineering Hiroshima University Higashi Hiroshima 739‐8521 Japan
| | - Yoshitomo Furushima
- Materials Characterization Laboratories Toray Research Center Inc. 3–7, Sonoyama 3‐chome Otsu Shiga 520‐8567 Japan
| | - Christoph Schick
- Institute of Physics and Competence Center CALOR University of Rostock Rostock 18051 Germany
- Butlerov Institute of Chemistry Kazan Federal University 18 Kremlyovskaya Street Kazan 420008 Russia
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18
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Kourtidou D, Klonos PA, Papadopoulos L, Kyritsis A, Bikiaris DN, Chrissafis K. Molecular mobility and crystallization of renewable poly(ethylene furanoate) in situ filled with carbon nanotubes and graphene nanoparticles. SOFT MATTER 2021; 17:5815-5828. [PMID: 34037062 DOI: 10.1039/d1sm00592h] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
We investigate the thermal transitions and molecular mobility in new nanocomposites of biobased poly(ethylene furanoate) (PEF), by calorimetry and dielectric spectroscopy, supplemented by X-ray diffraction, Fourier transform infra-red spectroscopy and polarized light microscopy. The emphasis is placed on the facilitation of the crystallization of PEF, which is in general low and slow due to structural limitations that result in poor nucleation. Tuning of the crystalline fraction (CF) and semicrystalline morphology are important for optimization of the mechanical performance and manipulation of the permeation of small molecules (e.g., in packaging applications). The nucleation and CF are successfully improved here by the in situ filling of PEF with 0.5-2.5 wt% of carbon nanotubes (CNTs) and graphene nanoplatelets (GNPs). The improvements are discussed in connection with weak or absent interfacial polymer-filler interactions. CNTs were found to be more effective in facilitating crystallization, as compared with GNPs, possibly due to their larger aspect ratio. The segmental dynamics of PEF are both accelerated and decelerated by the addition of GNP and CNT, respectively, with complex phenomena contributing to the effects, namely, nucleation, changes in molar mass and changes in the free volume. The molecular mobility of PEF is moderately affected 'directly' by the particles, whereas stronger effects are induced by crystallization (an indirect effect) and, furthermore, by the increase in the length of alkylene sequences on the chain. Local dynamics exhibit time scale disturbances when the temperature approaches that of the glass transition, which is proposed here to be a common characteristic in the case of mobilities originating from the polymer backbone for these as well as different polyesters. Despite the weak effects on molecular mobility, the role of the fillers as nucleating agents seems to be further exploitable in the frame of envisaged applications, as the use of such fillers in combination with thermal treatment offer possibilities for manipulating the semicrystalline morphology, ion transport and, subsequently, permeation of small molecules.
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Affiliation(s)
- Dimitra Kourtidou
- School of Physics, Advanced Material and Devices Laboratory, Aristotle University of Thessaloniki, GR-541 24, Thessaloniki, Greece.
| | - Panagiotis A Klonos
- Department of Chemistry, Laboratory of Polymer Chemistry and Technology, Aristotle University of Thessaloniki, GR-541 24, Thessaloniki, Greece. and Department of Physics, National Technical University of Athens, Zografou Campus, GR-15780, Athens, Greece
| | - Lazaros Papadopoulos
- Department of Chemistry, Laboratory of Polymer Chemistry and Technology, Aristotle University of Thessaloniki, GR-541 24, Thessaloniki, Greece.
| | - Apostolos Kyritsis
- Department of Physics, National Technical University of Athens, Zografou Campus, GR-15780, Athens, Greece
| | - Dimitrios N Bikiaris
- Department of Chemistry, Laboratory of Polymer Chemistry and Technology, Aristotle University of Thessaloniki, GR-541 24, Thessaloniki, Greece.
| | - Konstantinos Chrissafis
- School of Physics, Advanced Material and Devices Laboratory, Aristotle University of Thessaloniki, GR-541 24, Thessaloniki, Greece.
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19
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Bornani K, Rahman MA, Benicewicz B, Kumar S, Schadler L. Using Nanofiller Assemblies to Control the Crystallization Kinetics of High-Density Polyethylene. Macromolecules 2021. [DOI: 10.1021/acs.macromol.1c00341] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Kamlesh Bornani
- Department of Department of Mechanical Engineering, College of Engineering and Mathematical Sciences, University of Vermont, Burlington, Vermont 05405, United States
| | - Md Anisur Rahman
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
| | - Brian Benicewicz
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
| | - Sanat Kumar
- Department of Chemical Engineering, Columbia University, New York, New York 10027, United States
| | - Linda Schadler
- Department of Department of Mechanical Engineering, College of Engineering and Mathematical Sciences, University of Vermont, Burlington, Vermont 05405, United States
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20
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Thermal and electrical characterization of poly(vinyl)alcohol)/poly(vinylidene fluoride) blends reinforced with nano-graphene platelets. POLYMER 2021. [DOI: 10.1016/j.polymer.2021.123731] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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21
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Kritikos G, Karatasos K. Effect of Nanofiller Size on the Mechanical Properties of Poly(acrylic acid)/Graphene Oxide Nanocomposites. Macromolecules 2021. [DOI: 10.1021/acs.macromol.1c00515] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Georgios Kritikos
- Laboratory of Physical Chemistry, Department of Chemical Engineering, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - Kostas Karatasos
- Laboratory of Physical Chemistry, Department of Chemical Engineering, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
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22
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Szymoniak P, Qu X, Abbasi M, Pauw BR, Henning S, Li Z, Wang DY, Schick C, Saalwächter K, Schönhals A. Spatial inhomogeneity, interfaces and complex vitrification kinetics in a network forming nanocomposite. SOFT MATTER 2021; 17:2775-2790. [PMID: 33543739 DOI: 10.1039/d0sm01992e] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
A detailed calorimetric study on an epoxy-based nanocomposite system was performed employing bisphenol A diglycidyl ether (DGEBA) cured with diethylenetriamine (DETA) as the polymer matrix and a taurine-modified MgAL layered double hydroxide (T-LDH) as the nanofiller. The -NH2 group of taurine can react with DGEBA improving the interaction of the polymer with the filler. The combined X-ray scattering and electron microscopy data showed that the nanocomposite has a partially exfoliated morphology. Calorimetric studies were performed using conventional DSC, temperature modulated DSC (TMDSC) and fast scanning calorimetry (FSC) in the temperature modulated approach (TMFSC) to investigate the vitrification and molecular mobility dependent on the filler concentration. First, TMDSC and NMR were used to estimate the amount of the rigid amorphous fraction which consists of immobilized polymer segments at the nanoparticle surface. It was found to be 40 wt% for the highest filler concentration, indicating that the interface dominates the overall macroscopic properties and behavior of the material to a great extent. Second, the relaxation rates of the α-relaxation obtained by TMDSC and TMFSC were compared with the thermal and dielectric relaxation rates measured by static FSC. The investigation revealed that the system shows two distinct α-relaxation processes. Furthermore, two separate vitrification mechanisms were also found for a bulk network-former without geometrical confinement as also confirmed by NMR. This was discussed in terms of the intrinsic spatial heterogeneity on a molecular scale, which becomes more pronounced with increasing nanofiller content.
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Affiliation(s)
- Paulina Szymoniak
- Bundesanstalt für Materialforschung und -prüfung (BAM), Unter den Eichen 87, 12205 Berlin, Germany.
| | - Xintong Qu
- Bundesanstalt für Materialforschung und -prüfung (BAM), Unter den Eichen 87, 12205 Berlin, Germany.
| | - Mozhdeh Abbasi
- Institut für Physik - NMR, Martin-Luther-Universität Halle-Wittenberg, Betty-Heimann-Str. 7, 06120 Halle, Germany
| | - Brian R Pauw
- Bundesanstalt für Materialforschung und -prüfung (BAM), Unter den Eichen 87, 12205 Berlin, Germany.
| | - Sven Henning
- Fraunhofer-Institut für Mikrostruktur von Werkstoffen und Systemen IMWS, Walter-Hülse-Str. 1, 06120 Halle, Germany
| | - Zhi Li
- IMDEA Materials Institute, Eric Kandel 2, 28906 Getafe, Madrid, Spain
| | - De-Yi Wang
- IMDEA Materials Institute, Eric Kandel 2, 28906 Getafe, Madrid, Spain
| | - Christoph Schick
- University of Rostock, Institute of Physics and Competence Center CALOR, Albert-Einstein-Str. 23-24, 18059 Rostock, Germany and A. M. Butlerov Institute of Chemistry, Kazan Federal University, Kremlevskaya 18, 420008 Kazan, Russian Federation
| | - Kay Saalwächter
- Institut für Physik - NMR, Martin-Luther-Universität Halle-Wittenberg, Betty-Heimann-Str. 7, 06120 Halle, Germany
| | - Andreas Schönhals
- Bundesanstalt für Materialforschung und -prüfung (BAM), Unter den Eichen 87, 12205 Berlin, Germany.
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23
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Karava V, Siamidi A, Vlachou M, Christodoulou E, Zamboulis A, Bikiaris DN, Kyritsis A, Klonos PA. Block copolymers based on poly(butylene adipate) and poly(L-lactic acid) for biomedical applications: synthesis, structure and thermodynamical studies. SOFT MATTER 2021; 17:2439-2453. [PMID: 33491719 DOI: 10.1039/d0sm02053b] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
This work describes the synthesis of poly(butylene adipate) (PBAd), by melt polycondensation, poly(l-lactic acid) (PLLA), by ring opening polymerization, and the new block copolymer PLLA/PBAd in ratios 90/10, 95/5, 75/25 and 50/50. Due to the biocompatibility and low toxicity of neat PBAd and PLLA, these copolymers are suitable to be used in biomedical applications. The 1H and 13C nuclear magnetic resonance spectroscopy techniques were employed for structural characterization. The thermal transitions, with an emphasis on crystallization, were assessed by differential scanning calorimetry, supplemented by X-ray diffraction and polarized optical microscopy. Molecular mobility studies were conducted using two advanced techniques, broadband dielectric spectroscopy and thermally stimulated depolarization currents. The results from the structural techniques, in combination with each other, provided proof of the presence of PLLA and PBAd blocks and, moreover, the successful copolymer synthesis. The overall data showed that the different co-polymer compositions result directly in severe changes in the polymer crystal distribution and, indirectly, the formation of PBAd micro/nano domains surrounded by PLLA. Furthermore, it was demonstrated that both the continuity of the two polymers throughout the copolymer volume and the semicrystalline morphology can be tuned to a wide extent. The latter makes these systems quite promising envisaging biomedical applications, including the encapsulation of small molecules, e.g. drug solutions. The molecular mobility map was constructed for these systems for the first time, revealing the local (short scale) and segmental (larger nm scale) mobility of PBAd and PLLA, as well as intermediate behaviors of the copolymers.
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Affiliation(s)
- Vasiliki Karava
- Department of Pharmacy, Section of Pharmaceutical Technology, National and Kapodistrian University of Athens, Zografou Campus, 15784, Athens, Greece.
| | - Aggeliki Siamidi
- Department of Pharmacy, Section of Pharmaceutical Technology, National and Kapodistrian University of Athens, Zografou Campus, 15784, Athens, Greece.
| | - Marilena Vlachou
- Department of Pharmacy, Section of Pharmaceutical Technology, National and Kapodistrian University of Athens, Zografou Campus, 15784, Athens, Greece.
| | - Evi Christodoulou
- Department of Chemistry, Laboratory of Polymer Chemistry and Technology, Aristotle University of Thessaloniki, GR-541 24, Thessaloniki, Greece
| | - Alexandra Zamboulis
- Department of Chemistry, Laboratory of Polymer Chemistry and Technology, Aristotle University of Thessaloniki, GR-541 24, Thessaloniki, Greece
| | - Dimitrios N Bikiaris
- Department of Chemistry, Laboratory of Polymer Chemistry and Technology, Aristotle University of Thessaloniki, GR-541 24, Thessaloniki, Greece
| | - Apostolos Kyritsis
- Department of Physics, National Technical University of Athens (NTUA), Zografou Campus, 15780, Athens, Greece.
| | - Panagiotis A Klonos
- Department of Chemistry, Laboratory of Polymer Chemistry and Technology, Aristotle University of Thessaloniki, GR-541 24, Thessaloniki, Greece and Department of Physics, National Technical University of Athens (NTUA), Zografou Campus, 15780, Athens, Greece.
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24
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Papadopoulos L, Klonos PA, Terzopoulou Z, Psochia E, Sanusi OM, Hocine NA, Benelfellah A, Giliopoulos D, Triantafyllidis K, Kyritsis A, Bikiaris DN. Comparative study of crystallization, semicrystalline morphology, and molecular mobility in nanocomposites based on polylactide and various inclusions at low filler loadings. POLYMER 2021. [DOI: 10.1016/j.polymer.2021.123457] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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25
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Klonos PA, Papadopoulos L, Kasimatis M, Iatrou H, Kyritsis A, Bikiaris DN. Synthesis, Crystallization, Structure Memory Effects, and Molecular Dynamics of Biobased and Renewable Poly( n-alkylene succinate)s with n from 2 to 10. Macromolecules 2021. [DOI: 10.1021/acs.macromol.0c02109] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Panagiotis A. Klonos
- Department of Physics, National Technical University of Athens, Zografou Campus, Athens 15780, Greece
- Department of Chemistry, Laboratory of Polymer Chemistry and Technology, Aristotle University of Thessaloniki, Thessaloniki GR-541 24, Greece
| | - Lazaros Papadopoulos
- Department of Chemistry, Laboratory of Polymer Chemistry and Technology, Aristotle University of Thessaloniki, Thessaloniki GR-541 24, Greece
| | - Maria Kasimatis
- Department of Chemistry, University of Athens, Panepistimiopolis, Zografou, Athens 15771, Greece
| | - Hermis Iatrou
- Department of Chemistry, University of Athens, Panepistimiopolis, Zografou, Athens 15771, Greece
| | - Apostolos Kyritsis
- Department of Physics, National Technical University of Athens, Zografou Campus, Athens 15780, Greece
| | - Dimitrios N. Bikiaris
- Department of Chemistry, Laboratory of Polymer Chemistry and Technology, Aristotle University of Thessaloniki, Thessaloniki GR-541 24, Greece
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26
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Promoting Interfacial Interactions with the Addition of Lignin in Poly(Lactic Acid) Hybrid Nanocomposites. Polymers (Basel) 2021; 13:polym13020272. [PMID: 33467623 PMCID: PMC7830551 DOI: 10.3390/polym13020272] [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: 12/10/2020] [Revised: 01/08/2021] [Accepted: 01/10/2021] [Indexed: 01/06/2023] Open
Abstract
In this paper, the calorimetric response of the amorphous phase was examined in hybrid nanocomposites which were prepared thanks to a facile synthetic route, by adding reduced graphene oxide (rGO), Cloisite 30B (C30B), or multiwalled carbon nanotubes (MWCNT) to lignin-filled poly(lactic acid) (PLA). The dispersion of both lignin and nanofillers was successful, according to a field-emission scanning-electron microscopy (FESEM) analysis. Lignin alone essentially acted as a crystallization retardant for PLA, and the nanocomposites shared this feature, except when MWCNT was used as nanofiller. All systems exhibiting a curtailed crystallization also showed better thermal stability than neat PLA, as assessed from thermogravimetric measurements. As a consequence of favorable interactions between the PLA matrix, lignin, and the nanofillers, homogeneous dispersion or exfoliation was assumed in amorphous samples from the increase of the cooperative rearranging region (CRR) size, being even more remarkable when increasing the lignin content. The amorphous nanocomposites showed a signature of successful filler inclusion, since no rigid amorphous fraction (RAF) was reported at the filler/matrix interface. Finally, the nanocomposites were crystallized up to their maximum extent from the glassy state in nonisothermal conditions. Despite similar degrees of crystallinity and RAF, significant variations in the CRR size were observed among samples, revealing different levels of mobility constraining in the amorphous phase, probably linked to a filler-dimension dependence of space filling.
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27
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Jimenez AM, Altorbaq AS, Müller AJ, Kumar SK. Polymer Crystallization under Confinement by Well-Dispersed Nanoparticles. Macromolecules 2020. [DOI: 10.1021/acs.macromol.0c01479] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Andrew M. Jimenez
- Department of Chemical Engineering, Columbia University, New York, New York, 10027, United States
| | - Abdullah S. Altorbaq
- Department of Chemical Engineering, Columbia University, New York, New York, 10027, United States
| | - Alejandro J. Müller
- POLYMAT and Faculty of Chemistry, Basque Country University UPV/EHU, Paseo Lardizabal 3, 20018 Donostia-San Sebastián, Spain
- Ikerbasque, Basque Science Foundation, 48011 Bilbao, Spain
| | - Sanat K. Kumar
- Department of Chemical Engineering, Columbia University, New York, New York, 10027, United States
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28
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Soudmand BH, Shelesh‐Nezhad K, Salimi Y. A combined differential scanning calorimetry‐dynamic mechanical thermal analysis approach for the estimation of constrained phases in thermoplastic polymer nanocomposites. J Appl Polym Sci 2020. [DOI: 10.1002/app.49260] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Behzad H. Soudmand
- Division of Plastics and Composites Engineering, Department of Mechanical Engineering University of Tabriz Tabriz Iran
| | - Karim Shelesh‐Nezhad
- Division of Plastics and Composites Engineering, Department of Mechanical Engineering University of Tabriz Tabriz Iran
| | - Yaghob Salimi
- Division of Plastics and Composites Engineering, Department of Mechanical Engineering University of Tabriz Tabriz Iran
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29
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Delpouve N, Saiter-Fourcin A, Coiai S, Cicogna F, Spiniello R, Oberhauser W, Legnaioli S, Ishak R, Passaglia E. Effects of organo-LDH dispersion on thermal stability, crystallinity and mechanical features of PLA. POLYMER 2020. [DOI: 10.1016/j.polymer.2020.122952] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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30
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Monnier X, Cavallo D, Righetti MC, Di Lorenzo ML, Marina S, Martin J, Cangialosi D. Physical Aging and Glass Transition of the Rigid Amorphous Fraction in Poly( l-lactic acid). Macromolecules 2020. [DOI: 10.1021/acs.macromol.0c01182] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Xavier Monnier
- Donostia International Physics Center (DIPC), Paseo Manuel de Lardizabal 4, 20018 San Sebastián, Spain
| | - Dario Cavallo
- Department of Chemistry and Industrial Chemistry, University of Genoa, Via Dodecaneso 31, 16146 Genoa, Italy
| | - Maria Cristina Righetti
- CNR-IPCF, National Research Council - Institute for Chemical and Physical Processes, Via Moruzzi 1, 56124 Pisa, Italy
| | - Maria Laura Di Lorenzo
- CNR-IPCB, National Research Council - Institute of Polymers, Composites and Biomaterials, Via Campi Flegrei, 34, 80078 Pozzuoli, NA Italy
| | - Sara Marina
- POLYMAT, University of the Basque Country UPV/EHU, Av. de Tolosa 72, 20018 San Sebastián, Spain
| | - Jaime Martin
- POLYMAT, University of the Basque Country UPV/EHU, Av. de Tolosa 72, 20018 San Sebastián, Spain
- Ikerbasque - Basque Foundation for Science, 48013 Bilbao, Spain
| | - Daniele Cangialosi
- Donostia International Physics Center (DIPC), Paseo Manuel de Lardizabal 4, 20018 San Sebastián, Spain
- Centro de Física de Materiales CFM (CSIC-UPV/EHU) and Materials Physics Center MPC, Paseo Manuel de Lardizabal 5, 20018 San Sebastián, Spain
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Christodoulou E, Klonos PA, Tsachouridis K, Zamboulis A, Kyritsis A, Bikiaris DN. Synthesis, crystallization, and molecular mobility in poly(ε-caprolactone) copolyesters of different architectures for biomedical applications studied by calorimetry and dielectric spectroscopy. SOFT MATTER 2020; 16:8187-8201. [PMID: 32789409 DOI: 10.1039/d0sm01195a] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
In this work, we synthesized poly(ε-caprolactone) (PCL) and three copolyesters of different architectures based on three different alcohols, namely a three arm-copolymer based on 1% glycerol (PCL_Gly), a four arm-copolymer based on 1% pentaerythrytol (PCL_PE), and a linear block copolymer based on ∼50% methoxy-poly(ethylene glycol) (PCL_mPEG), all simultaneously with the ring opening polymerization (ROP) of PCL. Due to their biocompatibility and low toxicity, these systems are envisaged for use in drug delivery and tissue engineering applications. Due to the in situ ROP during the copolyesters synthesis, the molecular weight of PCL, Wm initially ∼62 kg mol-1, drops in the copolymers from ∼60k down to ∼5k. For the structure-properties investigation we employed differential scanning calorimetry (DSC and TMDSC), X-ray diffraction (XRD), nuclear magnetic resonance (NMR), Fourier transform infra red (FTIR) spectroscopy, polarized optical microscopy (POM), broadband dielectric spectroscopy (BDS) and isothermal water sorption. DSC revealed that the crystalline fraction of PCL increases whereas the crystallization rate drops in the copolymers in the order PCL ∼ PCL_Gly > PCL_PE ≫ PCL_mPEG, which coincides with that of decreasing Wm. In PCL_mPEG the major amount of PCL (87%) was found to crystallize while the majority of mPEG (92%) was found amorphous exhibiting constrained amorphous mobility and severely slower/weaker crystallization as compared to neat mPEG. Segmental dynamics in BDS, in agreement with DSC, is similar and in general slow for the samples of star-like structure for Wm ≥ 30k arising from PCL, whereas it is severely faster and enhanced in strength for the linear PCL_mPEG (lower Wm) copolymer arising from mPEG. For the latter system, the data provide indications for the formation of complex structures consisting of many small PCL crystallites surrounded by amorphous mPEG segments with constrained dynamics and severely suppressed hydrophilicity. These effects cannot be easily assessed by conventional XRD and POM, confirming the power of the dielectric technique. The overall recordings indicated that the different polymer architecture results in severe changes in the semicrystalline morphology, which demonstrates the potential for tuning the final product performance (permeability, mechanical).
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Affiliation(s)
- Evi Christodoulou
- Department of Chemistry, Laboratory of Polymer Chemistry and Technology, Aristotle University of Thessaloniki, GR-541 24, Thessaloniki, Greece.
| | - Panagiotis A Klonos
- Department of Chemistry, Laboratory of Polymer Chemistry and Technology, Aristotle University of Thessaloniki, GR-541 24, Thessaloniki, Greece. and Department of Physics, National Technical University of Athens (NTUA), Zografou Campus, 15780, Athens, Greece
| | - Kostas Tsachouridis
- Department of Chemistry, Laboratory of Polymer Chemistry and Technology, Aristotle University of Thessaloniki, GR-541 24, Thessaloniki, Greece.
| | - Alexandra Zamboulis
- Department of Chemistry, Laboratory of Polymer Chemistry and Technology, Aristotle University of Thessaloniki, GR-541 24, Thessaloniki, Greece.
| | - Apostolos Kyritsis
- Department of Physics, National Technical University of Athens (NTUA), Zografou Campus, 15780, Athens, Greece
| | - Dimitrios N Bikiaris
- Department of Chemistry, Laboratory of Polymer Chemistry and Technology, Aristotle University of Thessaloniki, GR-541 24, Thessaloniki, Greece.
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Schick C, Androsch R. The Origin of Annealing Peaks in Semicrystalline Polymers: Enthalpy Recovery or Melting? Macromolecules 2020. [DOI: 10.1021/acs.macromol.0c01879] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Christoph Schick
- Institute of Physics and Department Life, Light & Matter, Competence Center °CALOR, University of Rostock, Rostock 18051, Germany
- Butlerov Institute of Chemistry, Kazan Federal University, 18 Kremlyovskaya Street, Kazan 420008, Russia
| | - René Androsch
- Interdisciplinary Center for Transfer-oriented Research in Natural Sciences (IWE TFN), Martin Luther University Halle-Wittenberg, Halle/Saale 06099, Germany
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Interfacial phenomena and molecular dynamics in core-shell-type nanocomposites based on polydimethylsiloxane and fumed silica: Comparison between impregnation and the new mechano-sorption modification as preparation methods. POLYMER 2020. [DOI: 10.1016/j.polymer.2020.122876] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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34
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Klonos PA, Papadopoulos L, Terzopoulou Z, Papageorgiou GZ, Kyritsis A, Bikiaris DN. Molecular Dynamics in Nanocomposites Based on Renewable Poly(butylene 2,5-furan-dicarboxylate) In Situ Reinforced by Montmorillonite Nanoclays: Effects of Clay Modification, Crystallization, and Hydration. J Phys Chem B 2020; 124:7306-7317. [PMID: 32786716 DOI: 10.1021/acs.jpcb.0c04306] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
This study deals with poly(butylene 2,5-furan-dicarboxylate), PBF, a renewable bio-based polyester expected to replace non-eco-friendly fossil-based homologues. PBF exhibits excellent gas barrier properties, which makes it promising for packaging applications; however, its rather low and slow crystallinity affects good mechanical performance. The crystallization of this relatively new polymer is enhanced here via reinforcement by introduction in situ of 1 wt % montmorillonite, MMT, nanoclays of three types (functionalizations). We study PBF and its nanocomposites (PNCs) also from the basic research point of view, molecular dynamics. For this work, we employ the widely used combination of techniques, differential scanning calorimetry (DSC) with broad-band dielectric relaxation spectroscopy (BDS), supplemented by polarized light microscopy (PLM) and thermogravimetric analysis (TGA). In the PNCs, the crystalline rate and fraction, CF, were found to be strongly enhanced as these fillers act as additional crystallization nuclei. The improvements in crystallization here correlate quite well with those on the mechanical performance recorded recently; moreover, they occur in the same filler order, in particular, with increasing MMT interlayer distance (from ∼1 to ∼3 nm). In the amorphous fraction of the polymer, the chain diffusion (calorimetric Tg and dynamic α process) is easier in the PNCs due to their slightly smaller length, while in the semicrystalline state, it decelerates by crystal-induced constraints. The local polymer dynamics (β process, below Tg) was found to be independent of the PNC composition, however, sensitive to structural changes of the matrix. Finally, a filler-induced dynamics was additionally recorded in the PNCs (α* process), arising possibly from the polymer located at the MMT surfaces. α* follows the changes in polymer chain length and decelerates with crystallization, whereas its activation energy decreases with mild hydration. The combined results on α* with the DSC and TGA findings, provide proof for weak MMT-PBF interactions. Overall, our results, along with data from the literature, suggest that such furan-based polyesters reinforced with properly chosen nanofillers could potentially serve well as tailor-made PNCs for targeted applications.
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Affiliation(s)
- Panagiotis A Klonos
- Laboratory of Polymer Chemistry and Technology, Department of Chemistry, Aristotle University of Thessaloniki, GR-541 24 Thessaloniki, Greece.,Department of Physics, National Technical University of Athens, Zografou Campus, 157 80 Athens, Greece
| | - Lazaros Papadopoulos
- Laboratory of Polymer Chemistry and Technology, Department of Chemistry, Aristotle University of Thessaloniki, GR-541 24 Thessaloniki, Greece
| | - Zoi Terzopoulou
- Laboratory of Polymer Chemistry and Technology, Department of Chemistry, Aristotle University of Thessaloniki, GR-541 24 Thessaloniki, Greece
| | - George Z Papageorgiou
- Laboratory of Industrial and Food Chemistry, Chemistry Department, University of Ioannina, 451 10 Ioannina, Greece
| | - Apostolos Kyritsis
- Department of Physics, National Technical University of Athens, Zografou Campus, 157 80 Athens, Greece
| | - Dimitrios N Bikiaris
- Laboratory of Polymer Chemistry and Technology, Department of Chemistry, Aristotle University of Thessaloniki, GR-541 24 Thessaloniki, Greece
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Li W, Wang L, Dong X, Wang D. A Facile Strategy to Fabricate Antistatic Polyamide 1012/Multi-Walled Carbon Nanotube Pipes for Fuel Delivery Applications. Polymers (Basel) 2020; 12:polym12081797. [PMID: 32796634 PMCID: PMC7465873 DOI: 10.3390/polym12081797] [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: 06/21/2020] [Revised: 08/01/2020] [Accepted: 08/05/2020] [Indexed: 11/16/2022] Open
Abstract
Developing antistatic long chain polyamide (LCPA) resins and fabricating the corresponding fuel pipes are challenges but necessary. Herein, a facile but effective strategy was put forward to fabricate LCPA resins with a superior conductivity, meeting the requirements of electrostatic sub-conductors. The strategy was based on, first, the incorporation of a large amount (15 wt%) of multi-walled carbon nanotubes (MWCNTs) into a polyamide 1012 (PA1012) matrix as a master batch, which formed a dense conductive network. Subsequently, it was diluted with PA1012 granules to produce base resins, and the reprocessed nanocomposites with a critical content of MWCNTs (3 wt%) could generate an effectively interconnected conductive network, with sparse and thinning features. Using the base resins, fuel pipes for automobiles, petrol stations and high pressure applications were successfully fabricated, where the thin conductive network was transformed into a thick one due to external field-induced re-agglomeration of MWCNTs. In this way, the obtained fuel pipes combined excellent conductive and barrier properties, and mechanical properties at high and low temperatures. These comprehensive properties also arose from the uniform dispersion of MWCNTs in an LCPA matrix, even without coupling agents; the attractive interaction between MWCNTs and the polyamide chains contributed to their strong interface adhesion. Thus, this research provides a versatile approach to fabricating antistatic LCPA resins, which will certainly extend their application to vehicle fuel systems.
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Affiliation(s)
- Wanli Li
- Institute of Systems Engineering, Academy of Military Sciences, Beijing 102300, China;
| | - Lili Wang
- State Key Laboratory of Bio-Fibers and Eco-Textiles, Collaborative Innovation Center of Marine Biobased Fiber and Ecological Textile Technology, Institute of Marine Biobased Materials, Qingdao University, Qingdao 266071, China;
| | - Xia Dong
- Key Laboratory of Engineering Plastics, Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China;
- Correspondence: ; Tel.: +86-10-8261-8533
| | - Dujin Wang
- Key Laboratory of Engineering Plastics, Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China;
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Kritikos G. Exploring a unified description of the super-Arrhenius region above and below the glass transition temperature. SOFT MATTER 2020; 16:6902-6913. [PMID: 32647837 DOI: 10.1039/d0sm00539h] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
A new approach is presented in order to check whether the hypothesis of an Arrhenius component surviving in the α-relaxation region is consistent with experimental data. The temperature dependence of the dynamics in the whole glassy regime is described by an equation which assumes an Arrhenius component in the cooperative diffusion. Based on thermodynamic arguments, the dynamic heterogeneities close to the glass transition region are related to structural heterogeneities in a manner consistent with the idea of a sigmoidal shape in the cohesion energy. By doing so, a characteristic temperature which can be identified as the glass transition temperature (Tg) emerges, while an additional parameter for the extension of the super-Arrhenius region is introduced. In the analysis of experimental data, the activation energy parameter, determined from the temperature dependence of the β-relaxation, is fixed, and the relation between the experimental and the predicted glass transition temperature is examined. The results of this comparison support the idea that dynamics above and below Tg can be described in a unified manner. The proposed model is tested against experimental data of glass-forming liquids, polymers and polymer composites. In the latter systems, it is shown that the Arrhenius-like behavior characterizing the dynamics of the polymeric bound-layer can be accounted for by such an extension of the super-Arrhenius region.
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Affiliation(s)
- Georgios Kritikos
- Laboratory of Physical Chemistry, Department of Chemical Engineering, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece.
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37
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Szymoniak P, Pauw BR, Qu X, Schönhals A. Competition of nanoparticle-induced mobilization and immobilization effects on segmental dynamics of an epoxy-based nanocomposite. SOFT MATTER 2020; 16:5406-5421. [PMID: 32490484 DOI: 10.1039/d0sm00744g] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The complex effects of nanoparticles on a thermosetting material based on an anhydride cured DGEBA/boehmite nanocomposite with different particle concentrations are considered. A combination of X-ray scattering, calorimetry, including fast scanning calorimetry and temperature modulated calorimetry, and dielectric spectroscopy was employed to study the structure, the vitrification kinetics and the molecular dynamics of the nanocomposites. For the first time in the literature, for an epoxy-based composite, a detailed analysis of the X-ray data was carried out. Moreover, the unfilled polymer was found to be intrinsically heterogeneous, showing regions with different crosslinking densities, indicated by two separate dynamic glass transitions. The glass transition temperature decreases with increasing nanoparticle concentration, resulting from a change in the crosslinking density. Moreover, on the one hand, for the nanocomposites, the incorporation of nanofiller increased the number of mobile segments for low nanoparticle concentrations, due to the altered crosslinking density. On the other hand, for higher loading degrees, the number of mobile segments decreased, resulting from the formation of an immobilized interphase (RAF). The simultaneous mobilization and immobilization of the segmental dynamics cannot be separated unambiguously. By taking the sample with the highest number of mobile segments as a reference state, it was possible to estimate the amount of RAF.
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Affiliation(s)
- Paulina Szymoniak
- Bundesanstalt für Materialforschung und-prüfung (BAM), Unter den Eichen 87, 12205 Berlin, Germany.
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Sanusi OM, Papadopoulos L, Klonos PA, Terzopoulou Z, Hocine NA, Benelfellah A, Papageorgiou GZ, Kyritsis A, Bikiaris DN. Calorimetric and Dielectric Study of Renewable Poly(hexylene 2,5-furan-dicarboxylate)-Based Nanocomposites In Situ Filled with Small Amounts of Graphene Platelets and Silica Nanoparticles. Polymers (Basel) 2020; 12:E1239. [PMID: 32485937 PMCID: PMC7362010 DOI: 10.3390/polym12061239] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2020] [Revised: 05/22/2020] [Accepted: 05/22/2020] [Indexed: 11/21/2022] Open
Abstract
Poly(hexylene 2,5 furan-dicarboxylate) (PHF) is a relatively new biobased polyester prepared from renewable resources, which is targeted for use in food packaging applications, owing to its great mechanical and gas barrier performance. Since both properties are strongly connected to crystallinity, the latter is enhanced here by the in situ introduction in PHF of graphene nanoplatelets and fumed silica nanoparticles, as well as mixtures of both, at low amounts. For this investigation, we employed Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), X-ray diffraction (XRD) and dielectric spectroscopy (BDS). The fillers were found to improve crystallization in both the rate (increasing Tc) and fraction (CF), which was rationalized via the concept of fillers acting as crystallization agents. This action was found stronger in the case of graphene as compared to silica. BDS allowed the detection of local and segmental dynamics, in particular in PHF for the first time. The glass transition dynamics in both BDS (α relaxation) and DSC (Tg) are mainly dominated by the relatively high CF, whereas in the PHF filled uniquely with silica strong spatial confinement effects due to crystals were revealed. Finally, all samples demonstrated the segmental-like dynamics above Tg, which screens the global chain dynamics (normal mode).
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Affiliation(s)
- Olawale Monsur Sanusi
- INSA CVL, Univ. Tours, Univ. Orléans, LaMé, 3 Rue de la Chocolaterie, CS 23410, CEDEX 41034 Blois, France; (O.M.S.); (N.A.H.); (A.B.)
| | - Lazaros Papadopoulos
- Department of Chemistry, Laboratory of Polymer Chemistry and Technology, Aristotle University of Thessaloniki, GR-541 24 Thessaloniki, Greece; (L.P.); (Z.T.)
| | - Panagiotis A. Klonos
- Department of Chemistry, Laboratory of Polymer Chemistry and Technology, Aristotle University of Thessaloniki, GR-541 24 Thessaloniki, Greece; (L.P.); (Z.T.)
- Department of Physics, National Technical University of Athens, Zografou Campus, 15780 Athens, Greece;
| | - Zoi Terzopoulou
- Department of Chemistry, Laboratory of Polymer Chemistry and Technology, Aristotle University of Thessaloniki, GR-541 24 Thessaloniki, Greece; (L.P.); (Z.T.)
| | - Nourredine Aït Hocine
- INSA CVL, Univ. Tours, Univ. Orléans, LaMé, 3 Rue de la Chocolaterie, CS 23410, CEDEX 41034 Blois, France; (O.M.S.); (N.A.H.); (A.B.)
| | - Abdelkibir Benelfellah
- INSA CVL, Univ. Tours, Univ. Orléans, LaMé, 3 Rue de la Chocolaterie, CS 23410, CEDEX 41034 Blois, France; (O.M.S.); (N.A.H.); (A.B.)
- DRII, IPSA, 63 Boulevard de Brandebourg, 94200 Ivry-Sur-Seine, France
| | - George Z. Papageorgiou
- Laboratory of Industrial and Food chemistry, Chemistry Department, University of Ioannina, 45110 Ioannina, Greece;
| | - Apostolos Kyritsis
- Department of Physics, National Technical University of Athens, Zografou Campus, 15780 Athens, Greece;
| | - Dimitrios N. Bikiaris
- Department of Chemistry, Laboratory of Polymer Chemistry and Technology, Aristotle University of Thessaloniki, GR-541 24 Thessaloniki, Greece; (L.P.); (Z.T.)
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Papadopoulos L, Klonos PA, Tzetzis D, Papageorgiou GZ, Kyritsis A, Bikiaris DN. Effects of graphene nanoplatelets on crystallization, mechanical performance and molecular dynamics of the renewable poly(propylene furanoate). POLYMER 2020. [DOI: 10.1016/j.polymer.2020.122172] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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PA6 and Halloysite Nanotubes Composites with Improved Hydrothermal Ageing Resistance: Role of Filler Physicochemical Properties, Functionalization and Dispersion Technique. Polymers (Basel) 2020; 12:polym12010211. [PMID: 31952200 PMCID: PMC7023541 DOI: 10.3390/polym12010211] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Revised: 01/03/2020] [Accepted: 01/13/2020] [Indexed: 11/16/2022] Open
Abstract
Polyamide 6 (PA6) suffers from fast degradation in humid conditions due to hydrolysis of amide bonds, which limits its durability. The addition of nanotubular fillers represents a viable strategy for overcoming this issue, although the additive/polymer interface at high filler content can become privileged site for moisture accumulation. As a cost-effective and versatile material, halloysite nanotubes (HNT) were investigated to prepare PA6 nanocomposites with very low loadings (1-45% w/w). The roles of the physicochemical properties of two differently sourced HNT, of filler functionalization with (3-aminopropyl)triethoxysilane and of dispersion techniques (in situ polymerization vs. melt blending) were investigated. The aspect ratio (5 vs. 15) and surface charge (-31 vs. -59 mV) of the two HNT proved crucial in determining their distribution within the polymer matrix. In situ polymerization of functionalized HNT leads to enclosed and well-penetrated filler within the polymer matrix. PA6 nanocomposites crystal growth and nucleation type were studied according to Avrami theory, as well as the formation of different crystalline structures (α and γ forms). After 1680 h of ageing, functionalized HNT reduced the diffusion of water into polymer, lowering water uptake after 600 h up to 90%, increasing the materials durability also regarding molecular weights and rheological behavior.
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41
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Structuring poly (lactic acid) film with excellent tensile toughness through extrusion blow molding. POLYMER 2020. [DOI: 10.1016/j.polymer.2019.122091] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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42
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Klonos PA, Kluge M, Robert T, Kyritsis A, Bikiaris DN. Molecular dynamics, crystallization and hydration study of Poly(Propylene succinate) based Poly(Ester amide)s. POLYMER 2020. [DOI: 10.1016/j.polymer.2019.122056] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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43
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Mendibil X, Ortiz R, Sáenz de Viteri V, Ugartemendia JM, Sarasua JR, Quintana I. High Throughput Manufacturing of Bio-Resorbable Micro-Porous Scaffolds Made of Poly(L-lactide-co-ε-caprolactone) by Micro-Extrusion for Soft Tissue Engineering Applications. Polymers (Basel) 2019; 12:E34. [PMID: 31878300 PMCID: PMC7023538 DOI: 10.3390/polym12010034] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 12/18/2019] [Accepted: 12/22/2019] [Indexed: 11/17/2022] Open
Abstract
Porous scaffolds made of elastomeric materials are of great interest for soft tissue engineering. Poly(L-lactide-co-ε-caprolactone) (PLCL) is a bio-resorbable elastomeric copolymer with tailorable properties, which make this material an appropriate candidate to be used as scaffold for vascular, tendon, and nerve healing applications. Here, extrusion was applied to produce porous scaffolds of PLCL, using NaCl particles as a leachable agent. The effects of the particle proportion and size on leaching performance, dimensional stability, mechanical properties, and ageing of the scaffolds were analyzed. The efficiency of the particle leaching and scaffold swelling when wet were observed to be dependent on the porogenerator proportion, while the secant moduli and ultimate tensile strengths were dependent on the pore size. Porosity, swelling, and mechanical properties of the extruded scaffolds were tailorable, varying with the proportion and size of porogenerator particles and showed similar values to human soft tissues like nerves and veins (E = 7-15 MPa, σu = 7 MPa). Up to 300-mm length micro-porous PLCL tube with 400-µm thickness wall was extruded, proving extrusion as a high-throughput manufacturing process to produce tubular elastomeric bio-resorbable porous scaffolds of unrestricted length with tunable mechanical properties.
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Affiliation(s)
| | - Rocío Ortiz
- IK4-TEKNIKER, C/IñakiGoenaga 5, 20600 Eibar, Spain; (X.M.)
| | | | - Jone M. Ugartemendia
- Department of Mining-Metallurgy Engineering and Materials Science, School of Engineering, University of the Basque Country (EHU-UPV), 48013 Bilbao, Spain (J.-R.S.)
| | - Jose-Ramon Sarasua
- Department of Mining-Metallurgy Engineering and Materials Science, School of Engineering, University of the Basque Country (EHU-UPV), 48013 Bilbao, Spain (J.-R.S.)
| | - Iban Quintana
- IK4-TEKNIKER, C/IñakiGoenaga 5, 20600 Eibar, Spain; (X.M.)
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Leng J, Szymoniak P, Kang NJ, Wang DY, Wurm A, Schick C, Schönhals A. Influence of interfaces on the crystallization behavior and the rigid amorphous phase of poly(l-lactide)-based nanocomposites with different layered doubled hydroxides as nanofiller. POLYMER 2019. [DOI: 10.1016/j.polymer.2019.121929] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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45
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Siddique S, Smith GD, Yates K, Mishra AK, Matthews K, Csetenyi LJ, Njuguna J. Structural and thermal degradation behaviour of reclaimed clay nano-reinforced low-density polyethylene nanocomposites. JOURNAL OF POLYMER RESEARCH 2019. [DOI: 10.1007/s10965-019-1802-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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46
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Thermal characterization by DSC and TGA analyses of PVA hydrogels with organic and sodium MMT. Polym Bull (Berl) 2019. [DOI: 10.1007/s00289-019-02782-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Nikitin D, Madkour S, Pleskunov P, Tafiichuk R, Shelemin A, Hanuš J, Gordeev I, Sysolyatina E, Lavrikova A, Ermolaeva S, Titov V, Schönhals A, Choukourov A. Cu nanoparticles constrain segmental dynamics of cross-linked polyethers: a trade-off between non-fouling and antibacterial properties. SOFT MATTER 2019; 15:2884-2896. [PMID: 30849134 DOI: 10.1039/c8sm02413h] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Copper has a strong bactericidal effect against multi-drug resistant pathogens and polyethers are known for their resistance to biofilm formation. Herein, we combined Cu nanoparticles (NPs) and a polyether plasma polymer in the form of nanocomposite thin films and studied whether both effects can be coupled. Cu NPs were produced by magnetron sputtering via the aggregation in a cool buffer gas whereas polyether layers were synthesized by Plasma-Assisted Vapor Phase Deposition with poly(ethylene oxide) (PEO) used as a precursor. In situ specific heat spectroscopy and XPS analysis revealed the formation of a modified polymer layer around the NPs which propagates on the scale of a few nanometers from the Cu NP/polymer interface and then transforms into a bulk polymer phase. The chemical composition of the modified layer is found to be ether-deficient due to the catalytic influence of copper whereas the bulk polymer phase exhibits the chemical composition close to the original PEO. Two cooperative glass transition phenomena are revealed that belong to the modified polymer layer and the bulk phase. The former is characterized by constrained mobility of polymer segments which manifests itself via a 30 K increase of dynamic glass transition temperature. Furthermore, the modified layer is characterized by the heterogeneous structure which results in higher fragility of this layer as compared to the bulk phase. The Cu NPs/polyether thin films exhibit reduced protein adsorption; however, the constrained segmental dynamics leads to the deterioration of the non-fouling properties for ultra-thin polyether coatings. The films are found to have a bactericidal effect against multi-drug resistant Gram-positive Methicillin-Resistant Staphylococcus aureus and Gram-negative Pseudomonas aeruginosa.
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Affiliation(s)
- Daniil Nikitin
- Charles University, Faculty of Mathematics and Physics, Department of Macromolecular Physics, V Holešovičkách 2, Prague, Czech Republic.
| | - Sherif Madkour
- Bundesanstalt für Materialforschung und - prüfung (BAM), Unter den Eichen 87, 12205 Berlin, Germany.
| | - Pavel Pleskunov
- Charles University, Faculty of Mathematics and Physics, Department of Macromolecular Physics, V Holešovičkách 2, Prague, Czech Republic.
| | - Renata Tafiichuk
- Charles University, Faculty of Mathematics and Physics, Department of Macromolecular Physics, V Holešovičkách 2, Prague, Czech Republic.
| | - Artem Shelemin
- Charles University, Faculty of Mathematics and Physics, Department of Macromolecular Physics, V Holešovičkách 2, Prague, Czech Republic.
| | - Jan Hanuš
- Charles University, Faculty of Mathematics and Physics, Department of Macromolecular Physics, V Holešovičkách 2, Prague, Czech Republic.
| | - Ivan Gordeev
- Institute of Physics, Academy of Sciences of the Czech Republic, Cukrovarnická 10, 16200 Prague, Czech Republic
| | - Elena Sysolyatina
- Gamaleya National Research Center of Epidemiology and Microbiology, Gamaleya 18, 123098 Moscow, Russia
| | - Alexandra Lavrikova
- Gamaleya National Research Center of Epidemiology and Microbiology, Gamaleya 18, 123098 Moscow, Russia
| | - Svetlana Ermolaeva
- Gamaleya National Research Center of Epidemiology and Microbiology, Gamaleya 18, 123098 Moscow, Russia
| | - Valerii Titov
- G. A. Krestov Institute of Solution Chemistry of the Russian Academy of Sciences, Akademicheskaya 1, 153045 Ivanovo, Russia
| | - Andreas Schönhals
- Bundesanstalt für Materialforschung und - prüfung (BAM), Unter den Eichen 87, 12205 Berlin, Germany.
| | - Andrei Choukourov
- Charles University, Faculty of Mathematics and Physics, Department of Macromolecular Physics, V Holešovičkách 2, Prague, Czech Republic.
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Klonos PA, Goncharuk OV, Pakhlov EM, Sternik D, Deryło-Marczewska A, Kyritsis A, Gun’ko VM, Pissis P. Morphology, Molecular Dynamics, and Interfacial Phenomena in Systems Based on Silica Modified by Grafting Polydimethylsiloxane Chains and Physically Adsorbed Polydimethylsiloxane. Macromolecules 2019. [DOI: 10.1021/acs.macromol.9b00155] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Panagiotis A. Klonos
- Department of Physics, National Technical University of Athens, Zografou Campus, 15780 Athens, Greece
| | - Olena V. Goncharuk
- Chuiko Institute of Surface Chemistry, 17 General Naumov Street, 03164 Kiev, Ukraine
| | - Eugeniy M. Pakhlov
- Chuiko Institute of Surface Chemistry, 17 General Naumov Street, 03164 Kiev, Ukraine
| | - Dariusz Sternik
- Maria Curie-Sklodowska University, M. Curie-Sklodowska Sq. 3, 20-031 Lublin, Poland
| | | | - Apostolos Kyritsis
- Department of Physics, National Technical University of Athens, Zografou Campus, 15780 Athens, Greece
| | - Volodymyr M. Gun’ko
- Chuiko Institute of Surface Chemistry, 17 General Naumov Street, 03164 Kiev, Ukraine
| | - Polycarpos Pissis
- Department of Physics, National Technical University of Athens, Zografou Campus, 15780 Athens, Greece
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Terzopoulou Z, Klonos PA, Kyritsis A, Tziolas A, Avgeropoulos A, Papageorgiou GZ, Bikiaris DN. Interfacial interactions, crystallization and molecular mobility in nanocomposites of Poly(lactic acid) filled with new hybrid inclusions based on graphene oxide and silica nanoparticles. POLYMER 2019. [DOI: 10.1016/j.polymer.2019.01.041] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Klonos PA, Tegopoulos SN, Koutsiara CS, Kontou E, Pissis P, Kyritsis A. Effects of CNTs on thermal transitions, thermal diffusivity and electrical conductivity in nanocomposites: comparison between an amorphous and a semicrystalline polymer matrix. SOFT MATTER 2019; 15:1813-1824. [PMID: 30688327 DOI: 10.1039/c8sm02478b] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Two series of polymer nanocomposites (PNCs) based on amorphous styrene-butadiene rubber (SBR) and semicrystalline linear low-density polyethylene (PE) matrices were filled with 2-15 wt% carbon nanotubes (CNT) and were studied by employing calorimetry, dielectric spectroscopy and laser flash analysis. The electrical conductivity, σ, increased with CNT loading and similar values were exhibited for the two matrices, uniquely depending on the concentration of the CNTs, suggesting practically no effects of the crystalline fraction (CF) on σ. For both types of matrix, a fraction of the polymer was found to be immobilized (rigid amorphous fraction, RAF). For the amorphous SBR, the RAF in PNCs originates uniquely from the presence of the filler (RAFfiller up to 0.19 wt). On the other hand, for the semicrystalline PE, the RAF is significantly larger (0.4-0.6 wt) due to the severe contribution of the RAF around the crystals (RAFcrystal). The thermal diffusivity, α, is quite low in both types of PNCs and exhibits higher values in the semicrystalline matrix (PE-based PNCs). Our results suggest that in these PNCs, heat transport mechanisms are activated mainly in the crystalline domains, more so with the additive contribution of the RAFcrystal. In the amorphous SBR-based PNCs, heat transport is facilitated mainly by CNTs, whereas the RAFfiller is found to be a good measure of the thermal resistance behavior of CNT/polymer interphases and consequently, of thermal diffusivity. Direct correlation of the results obtained by the three techniques with each other revealed the systematic dependence of α on the amount of RAF in each matrix; the α(RAF) trends, however, are different for the two matrices. Furthermore, the results suggest that the two RAFs exhibit different structural characteristics, e.g. the RAFcrystal exhibits a more ordered structure than the RAFfiller; this issue is still an open debate in the literature.
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Affiliation(s)
- Panagiotis A Klonos
- Department of Physics, National Technical University of Athens, Zografou Campus, 15780, Athens, Greece.
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