الفهرس 
Introduction
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Abstract
In this thesis, low density polyethylene, low density polyethylene<U+2013> poly ( ethylene vinyl acetate )(80/20 ) and low density polyethylene <U+2013> poly (ethylene propylene diene rubber) (80/20) were mixed with polyfunctional monomers namely 1,6 <U+2013> hexandiol diacrylate (2 %) and Azodicarbonamide as foaming agent of different concentrations 0.5, 1, 1.5, 2.5, 5, 7.5 % . The specimens were hot pressed and exposed to electron beam irradiation at different irradiation doses namely 25, 50, 75 and 100 kGy for LDPE and LDPE/EVA and 5, 10, 15 and 20 kGy in case of using LDPE / EPDM . The irradiated samples were subjected to heating up to 225 oC to induce foaming . The effect of irradiation doses and foaming agent concentration on the various properties were followed up . The Rheology measurements reveals that incorporation of EVA in LDPE reduce the melt viscosity of the blend . On the other hand , EPDM increase the melt viscosity . This change was reflected on the low tensile strength of unirradiated and unfoamed LDPE/EVA blend and high tensile values of LDPE/EPDM compared to LDPE . Also , it can be seen that both irradiation dose and foaming agent concentration influence the stress strain curve, in which the stress value increases as irradiation dose increase, whereas, the elongation at rupture decreases .Increasing foaming agent concentration deteriorates both stress and strain for all specimens.