Magdy A. M. Ali

Studies on sand/clay unsaturated polyester composite materials

The effect of a radiation-initiated polyester on the physicomechanical prop- erties of a sand/clay-polyester composite has been investigated. The unsaturated poly- ester resins containing various styrene contents were used at different sand/clay composites from 10 to 70 wt % with respect to the weight of sand and clay together; polymerization was conducted using g-irradiation at 50 kGy. Also, different particle sizes of clay (namely 1.25- 0.80, 0.80 - 0.50, and ,0.50) were used. The compressive strength, apparent porosity, and water absorption—in addition to infrared spectroscopy of the composite samples—were studied. Results indicate that the compressive strength decreases with an increase in sand/clay, as well as the styrene content in the unsatur- ated polyester resin, whereas the apparent porosity and water absorption of the com- posite samples increase. Infrared spectra showed the appearance of new bands, which indicated a chemical reaction between polyester and clay constituents.

Waste newsprint fibers for reinforcement of radiation-cured styrene butadiene rubber-based composites - Part I: Mechanical and physical properties

In this study, waste newsprint paper fiber was treated by polystyrene emulsion and included as a filler in styrene butadiene rubber. Then, the composites were subjected to electron beam irradiation at different irradiation doses, and follow-up was done on the effect of irradiation dose and fiber concentration on mechanical and physical properties of prepared composites. The results indicated that the mechanical properties like tensile strength, elongation at break, stiffness, and toughness were enhanced by the increase of radiation and fiber content. Also, the physical properties like soluble fraction, swelling ratio, and volume fraction of rubber in swollen gel were enhanced by the increase of radiation and fiber content. On the other hand, scanning electron microscope (SEM) results confirmed that adhesion was situated between fiber and rubber matrix.