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Investigation of the structure and tensile strength of ultrahigh molecular weight polyethylene and amide functionalized single-walled carbon nanotubes nanocomposites. Polym Bull (Berl) 2023. [DOI: 10.1007/s00289-023-04681-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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2
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Taverna ME, Altorbaq AS, Kumar SK, Olmedo-Martínez JL, Busatto CA, Zubitur M, Mugica A, Nicolau VV, Estenoz DA, Müller AJ. Supernucleation Dominates Lignin/Poly(ethylene oxide) Crystallization Kinetics. Macromolecules 2022. [DOI: 10.1021/acs.macromol.2c00925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- María E. Taverna
- INTEC (UNL-CONICET), Güemes 3450, 3000 Santa Fe, Argentina
- UTN Regional San Francisco, Av. de la Universidad 501, 2400 San Francisco, Córdoba, Argentina
| | - Abdullah S. Altorbaq
- Department of Chemical Engineering, Columbia University, New York, New York 10027, United States
| | - Sanat K. Kumar
- Department of Chemical Engineering, Columbia University, New York, New York 10027, United States
| | - Jorge L. Olmedo-Martínez
- POLYMAT and Department of Polymers and Advanced Materials: Physics, Chemistry and Technology, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel de Lardizabal, 3, 20018 Donostia-San Sebastián, Spain
| | | | - Manuela Zubitur
- Chemical and Environmental Engineering Department, Polytechnic School, University of the Basque Country UPV/EHU, 20018 Donostia-San Sebastián, Spain
| | - Agurtzane Mugica
- POLYMAT and Department of Polymers and Advanced Materials: Physics, Chemistry and Technology, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel de Lardizabal, 3, 20018 Donostia-San Sebastián, Spain
| | - Verónica V. Nicolau
- UTN Regional San Francisco, Av. de la Universidad 501, 2400 San Francisco, Córdoba, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Godoy Cruz 2290, CABA, Argentina
| | | | - Alejandro J. Müller
- POLYMAT and Department of Polymers and Advanced Materials: Physics, Chemistry and Technology, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel de Lardizabal, 3, 20018 Donostia-San Sebastián, Spain
- IKERBASQUE, Basque Foundation for Science, Plaza Euskadi 5, 48009 Bilbao, Spain
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3
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Altorbaq AS, Krauskopf AA, Wen X, Pérez-Camargo RA, Su Y, Wang D, Müller AJ, Kumar SK. Crystallization Kinetics and Nanoparticle Ordering in Semicrystalline Polymer Nanocomposites. Prog Polym Sci 2022. [DOI: 10.1016/j.progpolymsci.2022.101527] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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4
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Shape fidelity and sterility assessment of 3D printed polycaprolactone and hydroxyapatite scaffolds. JOURNAL OF POLYMER RESEARCH 2021. [DOI: 10.1007/s10965-021-02675-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
AbstractPolycaprolactone (PCL) and hydroxyapatite (HA) composite are widely used in tissue engineering (TE). They are fit to being processed with three-dimensional (3D) printing technique to create scaffolds with verifiable porosity. The current challenge is to guarantee the reliability and reproducibility of 3D printed scaffolds and to create sterile scaffolds which can be used for in vitro cell cultures. In this context it is important for successful cell culture, to have a protocol in order to evaluate the sterility of the printed scaffolds. We proposed a systematic approach to sterilise 90%PCL-10%HA pellets using a 3D bioprinter before starting the printing process. We evaluated the printability of PCL-HA composite and the shape fidelity of scaffolds printed with and without sterilised pellets varying infill pattern, and the sterility of 3D printed scaffolds following the method established by the United States Pharmacopoeia. Finally, the thermal analyses supported by the Fourier Transform Infrared Spectroscopy were useful to verify the stability of the sterilisation process in the PCL solid state with and without HA. The results show that the use of the 3D printer, according to the proposed protocol, allows to obtain sterile 3D PCL-HA scaffolds suitable for TE applications such as bone or cartilage repair.
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Sangroniz L, Landa M, Fernández M, Santamaria A. Matching Rheology, Conductivity and Joule Effect in PU/CNT Nanocomposites. Polymers (Basel) 2021; 13:polym13060950. [PMID: 33808778 PMCID: PMC8003351 DOI: 10.3390/polym13060950] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 03/15/2021] [Accepted: 03/16/2021] [Indexed: 11/16/2022] Open
Abstract
We investigated polyurethane (PU)–carbon nanotube (CNT) nanocomposites (PU/CNT) in a range of concentrations from 1 to 8 wt% CNT as hot melt adhesives. We studied the thermal properties of the nanocomposites, which is relevant from an applied point of view. The phase angle plots versus complex modulus results revealed the existence of a maximum above a given CNT concentration. The intensity of the peak and associated relaxation time was analyzed with percolation theory, leading to a new method to determine the rheological percolation threshold. A lower threshold value was obtained from the electrical conductivity data, which was justified recalling that the hopping/tunnelling effect takes place in the nanocomposite, as stated by previous studies in the literature. Joule effect studies indicated that the heating effect was very significant, reaching temperature increases, ΔT, of 60 °C for low voltages. For the first time, the percolation equation was applied to the ΔT to obtain the corresponding threshold. Stimulus-responsive systems were conceived considering the correlation between the ΔT and the conductivity. The case of PU/CNT nanocomposites acting as hot melt adhesives that are welded/unglued by applying/removing an electrical voltage is presented.
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Affiliation(s)
- Leire Sangroniz
- POLYMAT and Department of Polymers and Advanced Materials: Physics, Chemistry and Technology, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel de Lardizábal, 3, 20018 Donostia-San Sebastián, Spain; (L.S.); (M.F.)
| | - Maite Landa
- FIBER PROFIL, Calle Bikuña Almirantea, 27, 20230 Legazpi, Gipuzkoa, Spain;
| | - Mercedes Fernández
- POLYMAT and Department of Polymers and Advanced Materials: Physics, Chemistry and Technology, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel de Lardizábal, 3, 20018 Donostia-San Sebastián, Spain; (L.S.); (M.F.)
| | - Antxon Santamaria
- POLYMAT and Department of Polymers and Advanced Materials: Physics, Chemistry and Technology, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel de Lardizábal, 3, 20018 Donostia-San Sebastián, Spain; (L.S.); (M.F.)
- Correspondence:
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6
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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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Arrigo R, Malucelli G. Rheological Behavior of Polymer/Carbon Nanotube Composites: An Overview. MATERIALS 2020; 13:ma13122771. [PMID: 32570902 PMCID: PMC7344594 DOI: 10.3390/ma13122771] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 06/15/2020] [Accepted: 06/16/2020] [Indexed: 11/16/2022]
Abstract
This paper reviews the current achievements regarding the rheological behavior of polymer-based nanocomposites containing carbon nanotubes (CNTs). These systems have been the subject of a very large number of scientific investigations in the last decades, due to the outstanding characteristics of CNTs that have allowed the formulation of nanostructured polymer-based materials with superior properties. However, the exploitation of the theoretical nanocomposite properties is strictly dependent on the complete dispersion of CNTs within the host matrix and on the consequent development of a huge interfacial region. In this context, a deep knowledge of the rheological behavior of CNT-containing systems is of fundamental importance, since the evaluation of the material's viscoelastic properties allows the gaining of fundamental information as far as the microstructure of nanofilled polymers is concerned. More specifically, the understanding of the rheological response of polymer/CNT nanocomposites reveals important details about the characteristics of the interface and the extent of interaction between the two components, hence allowing the optimization of the final properties in the resulting nanocomposites. As the literature contains plenty of reviews concerning the rheological behavior of polymer/CNT nanocomposites, this review paper will summarize the most significant thermoplastic matrices in terms of availability and relevant industrial applications.
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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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9
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Yang B, Zhang X, Wang C, Liu R, Fan B, Zhang H, Sun H. Effect of polyvinyl acetals on non-isothermal crystallization behaviour and mechanical properties of poly(ε-caprolactone). RSC Adv 2019; 9:36815-36824. [PMID: 35539042 PMCID: PMC9075173 DOI: 10.1039/c9ra08133j] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Accepted: 11/04/2019] [Indexed: 11/21/2022] Open
Abstract
Melt shearing made the crystallinity of as-received PCL increased and the crystallization temperature raised by 7.7 °C. Polyvinyl acetals increased the spherulite size of PCL from a few microns to 200 μm and PVB improved the Young’s modulus of PCL by 67%.
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Affiliation(s)
- Biao Yang
- School of Materials Science and Mechanical Engineering
- Beijing Technology and Business University
- Beijing 100048
- P. R. China
| | - Xin Zhang
- School of Materials Science and Mechanical Engineering
- Beijing Technology and Business University
- Beijing 100048
- P. R. China
| | - Chun Wang
- School of Materials Science and Mechanical Engineering
- Beijing Technology and Business University
- Beijing 100048
- P. R. China
| | - Ran Liu
- School of Materials Science and Mechanical Engineering
- Beijing Technology and Business University
- Beijing 100048
- P. R. China
| | - Baomin Fan
- School of Materials Science and Mechanical Engineering
- Beijing Technology and Business University
- Beijing 100048
- P. R. China
| | - Huijuan Zhang
- School of Materials Science and Mechanical Engineering
- Beijing Technology and Business University
- Beijing 100048
- P. R. China
| | - Hui Sun
- School of Materials Science and Mechanical Engineering
- Beijing Technology and Business University
- Beijing 100048
- P. R. China
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Klonos P, Sulym IY, Sternik D, Konstantinou P, Goncharuk OV, Deryło–Marczewska A, Gun'ko VM, Kyritsis A, Pissis P. Morphology, crystallization and rigid amorphous fraction in PDMS adsorbed onto carbon nanotubes and graphite. POLYMER 2018. [DOI: 10.1016/j.polymer.2018.02.020] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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11
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Gumede TP, Luyt AS, Hassan MK, Pérez-Camargo RA, Tercjak A, Müller AJ. Morphology, Nucleation, and Isothermal Crystallization Kinetics of Poly(ε-caprolactone) Mixed with a Polycarbonate/MWCNTs Masterbatch. Polymers (Basel) 2017; 9:polym9120709. [PMID: 30966008 PMCID: PMC6418913 DOI: 10.3390/polym9120709] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Revised: 11/20/2017] [Accepted: 12/08/2017] [Indexed: 11/16/2022] Open
Abstract
In this study, nanocomposites were prepared by melt blending poly (ε-caprolactone) (PCL) with a (polycarbonate (PC)/multi-wall carbon nanotubes (MWCNTs)) masterbatch in a twin-screw extruder. The nanocomposites contained 0.5, 1.0, 2.0, and 4.0 wt % MWCNTs. Even though PCL and PC have been reported to be miscible, our DSC (Differential Scanning Calorimetry), SAXS (Small Angle X-ray Scattering), and WAXS (Wide Angle X-ray Scattering) results showed partial miscibility, where two phases were formed (PC-rich and PCL-rich phases). In the PC-rich phase, the small amount of PCL chains included within this phase plasticized the PC component and the PC-rich phase was therefore able to crystallize. In contrast, in the PCL-rich phase the amount of PC chains present generates changes in the glass transition temperature of the PCL phase that were much smaller than those predicted by the Fox equation. The presence of two phases was corroborated by SEM, TEM, and AFM observations where a fair number of MWCNTs diffused from the PC-rich phase to the PCL-rich phase, even though there were some MWCNTs agglomerates confined to PC-rich droplets. Standard DSC measurements demonstrated that the MWCNTs nucleation effects are saturated at a 1 wt % MWCNT concentration on the PCL-rich phase. This is consistent with the dielectric percolation threshold, which was found to be between 0.5 and 1 wt % MWCNTs. However, the nucleating efficiency was lower than literature reports for PCL/MWCNTs, due to limited phase mixing between the PC-rich and the PCL-rich phases. Isothermal crystallization experiments performed by DSC showed an increase in the overall crystallization kinetics of PCL with increases in MWCNTs as a result of their nucleating effect. Nevertheless, the crystallinity degree of the nanocomposite containing 4 wt % MWCNTs decreased by about 15% in comparison to neat PCL. This was attributed to the presence of the PC-rich phase, which was able to crystallize in view of the plasticization effect of the PCL component, since as the MWCNT content increases, the PC content in the blend also increases. The thermal conductivities (i.e., 4 wt % MWCNTs) were enhanced by 20% in comparison to the neat material. The nanocomposites prepared in this work could be employed in applications were electrical conductivity is required, as well as lightweight and tailored mechanical properties.
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Affiliation(s)
- Thandi P Gumede
- Department of Chemistry, University of the Free State (Qwaqwa Campus), Private Bag X13, Phuthaditjhaba 9866, South Africa.
| | - Adriaan S Luyt
- Center for Advanced Materials, Qatar University, P.O. Box 2713 Doha, Qatar.
| | - Mohammad K Hassan
- Center for Advanced Materials, Qatar University, P.O. Box 2713 Doha, Qatar.
| | - Ricardo A Pérez-Camargo
- Polymat and Polymer Science and Technology Department, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel de Lardizabal 3, 20018 Donostia-San Sebastián, Spain.
| | - Agnieszka Tercjak
- Group 'Materials + Technologies' (GMT), Department of Chemical and Environmental Engineering, Faculty of Engineering, Gipuzkoa, University of the Basque Country UPV/EHU, 20018 Donostia-San Sebastián, Spain.
| | - Alejandro J Müller
- Polymat and Polymer Science and Technology Department, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel de Lardizabal 3, 20018 Donostia-San Sebastián, Spain.
- Ikerbasque, Basque Foundation for Science, 48013 Bilbao, Spain.
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