Nylon 6/PET Polymer Blends: Mechanical Properties of Fibers

Abstract

Nylon 6/PET (polyethylene terephthalate) polymer blends (PET varying from 10–50%) were melt spun into fibers. Their tensile properties (at room temperature) and dynamic mechanical properties (at 110 Hz from room temperature to 200°C) were studied. An increase in the initial modulus with increasing PET content was observed. The tenacity showed an increase and then a subsequent decrease after 70/30 nylon 6/PET composition. The blend fibers showed lower extensibility. Various theories connecting modulus and tenacity (independently) with composition, interfacial adhesion, and dispersed phase morphology helped to explain the observed tensile properties. The loss tangent maxima is shifted to a higher temperature with increased PET content in the blend fiber, while the relaxation peaks become broader up to a certain composition. Further, the storage modulus increases throughout with the increase in the PET content. The Takayanagi series and parallel models have been applied, and the results describe the structural and morphological features of the blend fiber, besides explaining some of the properties.