Multiwall carbon nanotube reinforced polyester nanocomposites

Abstract

This chapter presents the preparation of polymer nanocomposites and the effects of multiwall carbon nanotube (MWCNT) on the structure and properties of poly(ethylene 2,6-naphthalate) (PEN) nanocomposites. The combination of a very small quantity of relatively MWCNT with conventional cheap thermoplastic polymers provides attractive possibilities to improve physical properties of polymer composites, from a commercial perspective. MWCNT-reinforced PEN nanocomposites were prepared by a melt blending process in a twin screw extruder to create advanced materials for possible practical applications in numerous industrial fields. There are significant dependence of the crystallization behaviors and their kinetics of PEN/MWCNT nanocomposites on the MWCNT content, the cooling rate, and the crystallization temperature. The MWCNT in the PEN nanocomposites exhibited much higher nucleation activity than any nano-scaled reinforcement. In the PEN/MWCNT nanocomposites, the incorporation of the MWCNT promoted the nucleation and the growth with higher crystallization rate of the polymer nanocomposites, and simultaneously reduced the fold surface free energy and the works required in folding macromolecular chains in the polymer nanocomposites. The nonterminal behavior observed in the PEN/MWCNT nanocomposites was related to the dominant nanotube-nanotube interactions at higher MWCNT content, leading to the formation of the interconnected or network-like structures of the MWCNT in the PEN nanocomposites. The incorporation of very small quantity of the MWCNT significantly improved the mechanical properties of the PEN/MWCNT nanocomposites. There is a significant dependence of the thermal stability and degradation behavior of the PEN/MWCNT nanocomposites on the MWCNT content. The interconnected networklike structures of the MWCNT resulted in the physical barrier effect against thermaldegradation both by retarding thermal degradation and by preventing diffusion out of volatile decomposed products in the PEN nanocomposites, leading to the improvement in the thermal stability of the PEN/MWCNT nanocomposites. This present paper attempts for the first time to summarize the preparation, the non-isothermal crystallization kinetics, the crystallization and melting behavior, the rheological and mechanical properties, the thermal stability, and the thermal degradation kinetics of MWCNTreinforced PEN nanocomposites.