Structural (SRIM) composites, comprising up to 40 percent by volume of random continuous glass-fibre mats in a specially-developed copoly (urea-isocyanurate) (PUrI) matrix, have been formed via RIM. Mode I and Mode II interlaminar fracture tests, carried out in accordance with the ESIS Protocol, gave values of G_(Ic) and G_(IIc) an order of magnitued greater than those determined for unidirectional carbon-fibre/epoxy composites. G_(Ic) values for the SRIM composites are a factor of 2 to 3 greater than the unreinforced matrix and show significant variation due to extensive fibre-bridging during cracdk propagation. Low-energy (9.56J) impact tests on SRIM composites show an increase in maximum force with increasing V_f, but very little change in delamination-growth energy (E_g).
展开▼
