Aa. Hamza et al., 1-OPTO-THERMAL PROPERTIES OF FIBERS ANNEALING EFFECT ON THE BIREFRINGENCE VARIATIONS OF POLYESTER FIBERS, Journal of polymer science. Part B, Polymer physics, 36(4), 1998, pp. 555-565
Polyester(Egyptian) fibers were annealed at constant temperature( 190
degrees C) with different annealing times. Density, crystallinity, mea
n square density fluctuation, mechanical loss factor, and molecular or
ientation were calculated. Densities and mechanical loss factor were d
etermined using an acoustic method. Changes in the molecular orientati
on were evaluated from the resulting optical data using the polarizing
Pluta interference microscope. Correlation of data obtained by one me
thod with another leads to relational changes in optothermal propertie
s and in the molecular orientation. Changes of refractive index profil
es of annealed PET fibers are provided. Illustrations using graphs and
microinterferograms are shown. (C) 1998 John Wiley & Sons, Inc.