1-opto-thermal properties of fibers annealing effect on the birefringence variations of polyester fibers

摘要

Polyester(Egyptian) fibers were annealed at constant temperature( 190 degrees C) with different annealing times. Density, crystallinity, mean square density fluctuation, mechanical loss factor, and molecular orientation were calculated. Densities and mechanical loss factor were determined using an acoustic method. Changes in the molecular orientation were evaluated from the resulting optical data using the polarizing Pluta interference microscope. Correlation of data obtained by one method with another leads to relational changes in optothermal properties and in the molecular orientation. Changes of refractive index profiles of annealed PET fibers are provided. Illustrations using graphs and microinterferograms are shown. (C) 1998 John Wiley & Sons, Inc. [References: 44]