The effect of interfaces in multiphase polymers and composites upon their mechanical behaviour was investigated. A study was made of high speed crack propagation in polymethyl methacrylate toughened with 4-stage particles.
The optical method of transmitted caustics can be used to follow the increases in toughness which are found on the addition of second-phase rubber particles to a polymethyl methacrylate matrix, because these particulate composites retain good transparency. There is a continuous increase in the initiation value of the dynamic stress intensity factor as the volume fraction of particles increases. The principal toughening mechanism is shear yielding which causes crack tip blunting in the composites.
Funding SchemeCSC - Cost-sharing contracts