الفهرس 
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Abstract
Tailoring the properties of a polymer for specific application is a major task for many researches in the field of polymer science and polymer engineering. Different external effects are followed to alter the macromolecular structure of a polymer to a desirable arrangement. Strong magnetic fields (up to 10 Tesla) were applied either on the final stable product or during the polymerization of the polymer. Some relatively weak effectiveness were observed and documented. In the present work, a practical trial is done in order to initiate remarkably macromolecular structural variations by less strength magnetic fields. Powerful set of permanent magnets were used instead of the traditionally used big electromagnets and the field was inserted when the polymer structure was reached the minimum chain inter-attraction force. To examine the efficiency of the magnets collection to affect the polymeric structure, a special optical system is constructed to record effects of the magnetic field on the growth rate of polyethylene glycol (PEG) spherulites. A magnetic field of 355 mille Tesla (mT) accelerated the growth rate of spherulites markedly when the field lines are crossing the sample normally to its surface. When the field lines are passed tangential to the sample`s surface, 100 mT was enough to produce the same acceleration for the rate of spherulites growth, approximately. Polystyrene, as glassy polymer, film samples were treated magnetically during the phase transition from liquid to solid and then some physical properties in order to detect the type and amount of the magnetically induced variations. Polystyrene films were casted by two different techniques in order to know the better preparation method for inducing markedly magnetic changes. Infrared (IR) spectrum is measured to determine the induced chemical variations, if any. No chemical changes were detected in the hot pressed PS films in magnetic field strength up to 160 mT. PS samples that casted from a dilute solution showed absence of a mode of vibration at 2337 cm-1 from the samples subjected to 73 and 146 mT.. Mechanical properties of treated samples showed distinct variations, but are not in a systematic correlation with the strength of the applied magnetic field, which may be due to the selective effects of the molecular structure of PS. A model for the idea of selective effects of the magnetic field on polymeric structure and orientation is discussed. Obtained values of mechanical parameters are tabulated in single table for ease comparison. Some optical properties for the PS as optical material are measured and commented on. Refractive index, and hence dispersion of PS is greatly changed by the applied magnetic field. A magnetic field of 160 mT was able to eliminate the dispersive power of polystyrene. Probable optical applications for the magnetically modified polystyrene are discussed. All data are presented in coloured graphs and table. Some digital images for the PEG spherulites during growth are extracted from a video clip taken during the growing process using the special constructed optical system.