Nanocomposite fibers of poly(ethylene terephthalate) with montmorillonite and mica: thermomechanical properties and morphology

Abstract

The thermal stabilities, mechanical properties, and morphologies of nanocomposites of poly(ethylene terephthalate) (PET) with two different organoclays are compared. Dodecyltriphenylphosphoniummontmorillonite (C12PPh-MMT) and dodecyltriphenylphosphonium-mica (C12PPh-Mica) were used as reinforcing fillers in the fabrication of PET hybrid fibers. The variations of their properties with organoclay content in the polymer matrix and draw ratio (DR) are discussed. Transmission electron microscopy micrographs show that some of the clay layers are dispersed homogeneously within the polymer matrix on the nanoscale, although some clay particles are agglomerated. It was also found that the addition of only a small amount of organoclay is enough to improve the thermal stabilities and mechanical properties of the PET hybrid fibers. Even polymers with low organoclay contents (1 - 5 wt%) were found to exhibit much higher strength and modulus values than pure PET. In the case Of C12PPh-MMT/PET, the values of the tensile mechanical properties of the hybrid fibers were found to decrease linearly with increases in DR from 1 to 16. However, the tensile mechanical properties of the C12PPh-Mica hybrid fibers were found to be independent of DR. (c) 2006 Society of Chemical Industry.