Analysis of structural development during superdrawing of poly(ethylene terephthalate) fibers

Superdrawing;Stress-strain modeling;Crystallization;Fiber drawing;PET

Jain, Vibhor ; Polymer, Textile and Fiber Engineering

University:Georgia Institute of Technology

Department:Polymer, Textile and Fiber Engineering

关键词: Superdrawing;    Stress-strain modeling;    Crystallization;    Fiber drawing;    PET;   

Others  :  https://smartech.gatech.edu/bitstream/1853/28185/1/jain_vibhor_200905_phd.pdf

美国|英语

来源: SMARTech Repository

【 摘 要 】

A comprehensive experimental study was conducted to determine the limitations in processing conditions for superdrawing. Experimental studies were carried out by uniaxial drawing tests at temperatures from 90 to 120°C and at strain rates ranging from 0.008/s to 0.425/s. Crystallinity and orientation of the drawn samples were evaluated using differential scanning calorimetry and birefringence measurements. This study revealed that increasing temperature from 110°C to 120°C leads to more crystallization at low strain rates (0.001/s), and less crystallization at high strain rates (0.1/s). Furthermore, it was shown for the first time that the mechanism of crystallinity development in PET undergoes a transition at draw temperature of 113°C and strain rate of 0.17/s. A new one-dimensional constitutive model was developed to predict the stress-strain behavior of PET fibers as they are drawn to very large draw ratios (up to 10) over a wide range of temperature (90-120°C) and strain rate (0.008-0.425/s). The model was based on the rubber elasticity theory and non-linear viscoelasticity.