Effect of Particle Size on Impact Fracture Energy of Reprocessed Thermosetting Resins

Abstract

Epoxy and unsaturated polyester resins are typical thermosetting resins used as matrix for composites, and generally difficult to recycle. In this study, reprocessed epoxy and unsaturated polyester resins were prepared with ground epoxy or unsaturated polyester resin. We measured the impact fracture energy of reprocessed epoxy and unsaturated polyester resins with different volume fraction of ground epoxy or unsaturated polyester resin. The impact fracture energy lowered with increasing the size and the volume fraction of ground resins. The impact fracture energy of reprocessed resin was described by the sum of the fracture energy of the matrix resin and the mixed ground particles and the energy necessary to strip the ground particles on the fracture surface. The calculated values of the impact fracture energy were almost agreed the experimental values. It was found that in any resin, the impact fracture energy of the matrix resin mainly contributes to the impact fracture energy.