OPTOTHERMAL PROPERTIES OF FIBERS - XI - THE EFFECT OF THERMAL ANNEALING OF DRAWING BEHAVIOR FOR EGYPTIAN POLYESTER FIBERS ON THE CRYSTALLINITY AND SOME OPTICAL-PARAMETERS
Aa. Hamza et al., OPTOTHERMAL PROPERTIES OF FIBERS - XI - THE EFFECT OF THERMAL ANNEALING OF DRAWING BEHAVIOR FOR EGYPTIAN POLYESTER FIBERS ON THE CRYSTALLINITY AND SOME OPTICAL-PARAMETERS, Journal of applied polymer science, 68(9), 1998, pp. 1371-1386
The structure developed of annealed Egyptain poly(ethyleneterephthalat
e) (PET) fibers is studied interferometerically due to the drawing pro
cess. Using a two-beam Pluta polarizing interference microscope connec
ted to a device to dynamically study the draw ratio with the birefring
ence changes, the relations of drawing changes with some optical param
eters are given. The evaluation of density, the mean square density fl
uctuation [eta(2)], crystallinity, amorphous orientation, crystalline
orientation functions, number of chains per unit volume N-c, and numbe
r of random links between the network junction points N has been found
. The results obtained clarify the effect of annealing time and temper
ature with different draw ratios on the structure of PET fibers. Empir
ical formula is suggested to correlate the changes in f(theta), theta,
Delta n(a), and A with the draw ratio. Microinterferograms and curves
are given for illustration. (C) 1998 John Wiley & Sons, Inc.