37-41Structural changes of polyester
yarn with false-twist draw texturing parameters have been studied using a high-temperature
heater, high texturing speeds, short residence time in the heater and a short
yarn path. The dependence of three structural parameters, viz. crystalline
orientation, crystal size and birefringence, on texturing temperature, yarn
residence time in the heater and draw ratio has also been studied. At high
texturing speeds, the crystalline orientation and crystal size decrease due to
low thermal input. Crystalline orientation tends to increase at high texturing
temperatures and draw ratios