Studies on epoxy modified with recycled rubber

This work covers studies on systems with car tire regrind used as the tough ening phase in epoxy resins. Different surface modification techniques were used to improve the compatibility at the interface between the rubber part icles and the epoxy matrix Silane coupling agents, plasma surface modificat ion and acrylic acid/benzoylperoxide were used to enhance the surface prope rties of rubber particles. Rubber parts of ground used car tires, with or w ithout surface treatment, were mixed with epoxy. This mixture was poured in to molds to obtain mechanical test specimens according to ASTM standards. A fter curing, mechanical tests were performed and the fractured surfaces of the specimens were examined under Scanning Electron Microscopy. SEM. Throug hout the studies, changes in mechanical properties were followed by an incr ease in the volume percentage of rubber particles and by the effect of diff erent surface treatment processes applied on rubber. A decrease in tensile properties and impact resistance was observed in general as compared to unm odified epoxy. On the other hand, slight increases in fracture toughness va lues were observed in all surface treated cases.