الفهرس 
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Abstract
The work presented in this thesis focuses attention on developing the prorates of
polymer materials by means of the drawing and blending of some synthctic polymers.
Both drawing and blending processes change the molecular invironment and hence. The creation of new structure which tends to optimise polymeric properties is expected. The drawing process, on the one hand, produces an orientation in crystalline polymers. The orientation phenomenon has proved a great advantage in gaining greater insight at a micro-structure level when investigating mechanical properties. On the other hand, the blending of two or more polymers seeks to optimise properties by combining the best features of the different components. As a result, the drawing and blending of polymers are very important commercially and are of much industrial interest. , The work presented comes under two main headings:
I-a A Study of the Optical Properties of Polyethylene (PE) and Nylon 6 Fibers
Different specimens were subjected to mechanic~.!l drawing at room temperature
using an opto-mechanical device attached to a microscope stage. The effect of drawing on specific optical properties such as the refractive indices for the two principal vibration directions (parallel and at right angles to the fiber axis), and the ,birefringence, were investigated. from the interferograms obtained and through the application of the appropriate I)1athematical equations, the refractive indices and the birefringence values were determined and drawn as functions of the draw ratios. The results show that, with light vibrating parallel to the fiber axis the refractive index drastically increased with the draw ratio until it was nearly saturated. whereas with light vibrating normal to the fiber axis the refractive index decreased drastically and at specific draw ratios it was nearly saturated.