Abstract
Poly(ethylene terephthalate)/organo-modified-montmorillonite (o-MMT) nanocomposites were prepared via melt compounding. A polyester ionomer was used as a compatibilizer to increase the interaction between the nanoclay and PET. The nominal o-MMT content was 2 wt.% and the ionomer/organoclay (mass ratio) was 3:1. The samples were characterized by WAXD, SEM, TEM, TGA, rheometry, DSC, O2 permeation and tensile testing. It was found that the addition of the ionomer improved the dispersion of the nanoclay particles in the PET matrix, leading to an exfoliated structure for the samples prepared by twin screw extrusion and by an internal mixer (Brabender). This was confirmed by larger complex viscosity and storage modulus at low frequency for molten samples. However, a subsequent processing using single screw extrusion to produce films resulted in thermal degradation of the organo-modifier of the clay and collapse of the gallery spacing. DSC results revealed that the cold crystallization temperature of nanocomposites-based films decreased and the melt crystallization temperature increased with the introduction of the organoclay, due to the strong heterogeneous nucleation effect of the clay particles. The tensile modulus of extruded films increased, while the yield strength remained constant with the incorporation of the organoclay. The oxygen permeability of PET-ionomer nanocomposites decreased as compared with samples containing no ionomer.
References
Ammala, A., et al.: “Poly(ethylene terephthalate) Clay Nanocomposites: Improved Dispersion Based on a Aqueous Ionomer”, Compos. Sci. Technol., 68, 1328–1337(2008), DOI: 10.1016/j.compscitech.2007.12.012Search in Google Scholar
Barber, G. D., et al., “Poly(ethylene terephthalate) Ionomer Based Clay Nanocomposites Produced via Melt Extrusion”, Polymer., 46, 6706–6714(2005), DOI: 10.1016/j.polymer.2005.05.024Search in Google Scholar
Basu, S. K., Tewari, A., “Transmission Electron Microscopy Based Direct Mathematical Quantifiers for Dispersion in Nanocomposites”, Appl. Phys. Lett., 91, 053105(2007), DOI: 10.1063/1.2760182Search in Google Scholar
Boykin, T. L., Moore, R. B., “The Role of Specific Interactions and Transreactions on the Compatibility of Polyester Ionomers with Poly(ethylene terephthalate) and Nylon 6,6”, Polym. Eng. Sci., 38, 1658–1665(1998), DOI: 10.1002/pen.10336Search in Google Scholar
Chisholm, B. J., et al., “Nanocomposites Derived from Sulfonated Poly(butylene terephthalate)”, Macromolecules, 35, 5508–5516(2002), DOI: 10.1021/ma012224nSearch in Google Scholar
Cho, J. W., Paul, D. R., “Nylon 6 Nanocomposites by Melt Compounding”, Polymer, 42, 1083–1094(2001), DOI: 10.1016/S0032-3861(00)00380-3Search in Google Scholar
Dennis, H. R., et al., “Effect of Melt Processing Conditions on the Extent of Exfoliation in Organoclay-based Nanocomposites”, Polymer, 42, 9513–9522(2001), DOI: 10.1016/S0032-3861(01)00473-6Search in Google Scholar
Eckel, D. F., et al., “Assessing Organo-clay Dispersion in Polymer Nanocomposites”, J. Appl. Polym. Sci., 93, 1110–1117(2004), DOI: 10.1002/app.20566Search in Google Scholar
Fornes, T. D., et al., “Nylon 6 Nanocomposites: The Effect of Matrix Molecular Weight”, Polymer, 42, 09929–09940(2001), DOI: 10.1016/S0032-3861(01)00552-3Search in Google Scholar
Fornes, T. D., et al., “Polymer Matrix Degradation and Color Formation in Melt Processed Nylon 6/Clay Nanocomposites”, Polymer, 44, 7545–7556(2003), DOI: 10.1016/j.polymer.2003.09.034Search in Google Scholar
Fornes, T. D., et al., “Effect of Sodium Montmorillonite Source on Nylon 6/Clay Nanocomposites”, Polymer, 45, 2321–2331(2004), DOI: 10.1016/j.polymer.2004.01.061Search in Google Scholar
Gashemi, H., et al., “Effect of Processing Conditions on Properties of PET/Clay Nanocomposite Films”, Int. Polym. Proc., 25, 219–228(2011), DOI: 10.3139/217.2446Search in Google Scholar
Ge, C. H., et al., “Isothermal Crystallization Kinetics and Melting Behavior of Poly(ethylene terephthalate)/Barite Nanocomposites”, J. Polym. Sci., Part B: Polym. Phys., 47, 655–668(2009), DOI: 10.1002/polb.21669Search in Google Scholar
Gilman, J. W., “Flammability and Thermal Stability Studies of Polymer Layered-silicate (Clay) Nanocomposites”, Appl. Clay Sci., 15, 31–49(1999), DOI: 10.1016/S0169-1317(99)00019-8Search in Google Scholar
Gilman, J. W., et al., “Flammability Properties of Polymer-Layered-Silicate Nanocomposites. Polypropylene and Polystyrene Nanocomposites”, Chem. Mater., 12, 1866–1873(2000), DOI: 10.1021/cm0001760Search in Google Scholar
Gurmendi, U., et al., “Structure and Properties of a New Polymer Nanocomposite Based on a Poly(hydroxy ether of bisphenol A) Matrix”, Compos. Sci. Technol., 66, 1221–1228(2006), DOI: 10.1016/j.compscitech.2005.10.033Search in Google Scholar
Imai, Y., et al., “High-modulus Poly(ethylene terephthalate)/Expandable Fluorine Mica Nanocomposites with a Novel Reactive Compatibilizer”, Chem. Mater., 14, 477–479(2002), DOI: 10.1021/cm010408aSearch in Google Scholar
Krikorian, V., Pochan, D. J., “Poly(l-Lactic Acid)/Layered Silicate Nanocomposite: Fabrication, Characterization, and Properties”, Chem. Mater., 15, 4317–4324(2003), DOI: 10.1021/cm034369+Search in Google Scholar
Lee, S., et al., “Exfoliation of Layered Silicate Facilitated by Ring-opening Reaction of Cyclic Oligomers in PET Clay Nanocomposites”, Polymer, 46, 2201–2210(2005), DOI: 10.1016/j.polymer.2005.01.006Search in Google Scholar
Luo, Z. P., Koo, J. H., “Quantification of the Layer Dispersion Degree in Polymer Layered Silicate Nanocomposites by Transmission Electron Microscopy” Polymer, 49, 1841–1852(2008), DOI: 10.1016/j.polymer.2008.02.028Search in Google Scholar
Messersmith, P. B., Giannelis, E. P., “Synthesis and Barrier Properties of Poly(e-caprolactone)-layered Silicate Nanocomposites”, J. Polym. Sci., Part A: Polym. Chem., 33, 1047–1057(1995), DOI: 10.1002/pola.1995.080330707Search in Google Scholar
Nielsen, L. E., “Models for the Permeability of Filled Polymers”, J. Macromol. Sc. Chem., 5, 929–942(1967), DOI: 10.1080/10601326708053745Search in Google Scholar
Phang, I. Y., et al. “Crystallization and Melting Behavior of Polyester/Clay Nanocomposites”, Polym. Int., 53, 1282–1289(2004), DOI: 10.1002/pi.1513Search in Google Scholar
Pluta, M., “Melt Compounding of Polylactide/Organoclay: Structure and Properties of Nanocomposites”, J. Polym. Sci., Part B: Polym. Phys, 44, 3392–3405(2006), DOI: 10.1002/polb.20957Search in Google Scholar
Qiu, G., et al., “Dual Melting Endotherms in the Thermal Analysis of Poly(ethylene terephthalate)”, J. Appl. Polym. Sci., 69, 729–742(1998), DOI: 10.1002/(SICI)1097-4628(19980725)69:4<729::AID-APP11>3.0.CO;2-KSearch in Google Scholar
Ray, S. S., Okamoto, M., “Polymer–layered Silicate Nanocomposite: A Review from Preparation to Processing”, Prog. Polym. Sci., 28, 1539–641(2003), DOI: 10.1016/j.progpolymsci.2003.08.002Search in Google Scholar
Ray, S. S., Bousmina, M., “Biodegradable Polymers and Their Layered Silicate Nanocomposites: in Greening the 21st Century Materials World”, Prog. Mater. Sci., 50, 962–1079(2005), DOI: 10.1016/j.pmatsci.2005.05.002Search in Google Scholar
Sanchez-Solis, A., et al., “Production of Nanocomposites of PET-montmorillonite Clay by an Extrusion Process”, Macromol. Symp., 192, 281–292(2003), DOI: 10.1002/masy.200390038Search in Google Scholar
Saujanya, C., et al., “Structure and Thermal Properties of Compatibilized PET/Expandable Fluorine Mica Nanocomposites”, Polym. Bull., 49, 69–76(2002), DOI: 10.1007/s00289-002-0072-5Search in Google Scholar
Saujanya, C., et al., “Structure Development and Isothermal Crystallization Behaviour of Compatibilized PET/Expandable Fluorine Mica Hybrid Nanocomposite”, Polym. Bull., 51, 85–92(2003), DOI: 10.1007/s00289-003-0197-1Search in Google Scholar
VanderHart, D. L., et al., “NMR Measurements Related to Clay-dispersion Quality and Organic-Modifier Stability in Nylon-6/Clay Nanocomposites”, Macromolecules, 34, 3819–3822(2001), DOI: 10.1021/ma002089zSearch in Google Scholar
Vermogen, A., et al., “Evaluation of the Structure and Dispersion in Polymer-layered Silicate Nanocomposites”, Macromolecules, 38, 9661–9669(2005), DOI: 10.1021/ma051249+Search in Google Scholar
Vidotti, S. E., et al., “Preparation of Poly(ethylene terephthalate)/Organoclay Nanocomposites Using a Polyester Ionomer as a Compatibilizer”, J. Polym. Sci., Part B: Polym. Phys., 45, 3084–3091(2007), DOI: 10.1002/polb.21311Search in Google Scholar
Wagener, R., Reisinger, T. J. G., “A Rheological Method to Compare the Degree of Exfoliation of Nanocomposites”, Polymer, 44, 7513–7518(2003), DOI: 10.1016/j.polymer.2003.01.001Search in Google Scholar
Xie, S. B., et al., “Quantitative Characterization of Clay Dispersion in Polypropylene-clay Nanocomposites by Combined Transmission Electron Microscopy and Optical Microscopy”, Materials Letters, 64, 185–188(2010), DOI: 10.1016/j.matlet.2009.10.042Search in Google Scholar
Zhao, J., et al., “Rheological Characterization of Polystyrene–Clay Nanocomposites to Compare the Degree of Exfoliation and Dispersion” Polymer, 46, 8641–8660(2005), DOI: 10.1016/j.polymer.2005.04.038Search in Google Scholar
Zhu, J., et al., “Fire Properties of Polystyrene-Clay Nanocomposites”, Chem. Mater., 13, 3774–3780(2001), DOI: 10.1021/cm000984rSearch in Google Scholar
Zhu, J., et al., “Studies on the Mechanism by which the Formation of Nanocomposites Enhances Thermal Stability”, Chem. Mater., 13, 4649–4654(2001), DOI: 10.1021/cm010451ySearch in Google Scholar
© 2011, Carl Hanser Verlag, Munich