Physical Properties of R-PET/CD-PET Polyblended Hollow Filaments and Their Kinetics of Alkaline Hydrolysis

Abstract

Cationic dyeable poly(ethylene terephthalate) (CD-PET) was formed by copolymerizing dimethylterephthalate (DMT),5-sodium sulfonate dimethyl isophthalate (SIPM) with a molar ratio of 2% and ethylene glycol (EG). Blends of regular poly(ethylene terephthalate) (R-PET) and CD-PET were spun into hollow filaments. The filaments were then treated with aqueous NaOH. This study investigated the physical properties of R-PET/CD-PET polyblended hollow filaments and their kinetic behavior of alkaline hydrolysis using differential scanning calorimetry (DSC), wide angle x-ray diffraction (WAXD), the density gradient method, gel permeation chromatography (GPC), rheometer measurement and statistical analysis using the regression method. Experimental results indicate that the rate constant of alkaline hydrolysis was CD-PET hollow filaments >R-PET/CD-PET polyblended hollow filaments > R-PET hollow filaments. For the alkaline hydrolysis kinetics equation of R-PET, CD-PET/R-PET polyblended and CD-PET hollow filaments: −dW/dt=KCαAβ, β is equal to 1. Moreover, R2 of the kinetics equation for α from 1.06∼1.29 was better than that of α=1.