Repair of acrylic/glass composites by liquid resin injection and press moulding

This paper presents repair methods for in-situ polymerised acrylic (Elium®)/glass fibre (GF) composites focusing on mode-I fracture toughness recovery. GF/acrylic composites were first subjected to double cantilever beam (DCB) tests to measure their Mode-I fracture toughness. The delaminated samples after DCB tests were repaired and rejoined. Two repair methods were performed: liquid resin injection and press moulding at two different temperatures (130 °C and 160 °C). The repaired samples were subjected to a second set of DCB tests. The fracture behaviours of the four specimen groups (virgin, resin-injected, pressed at 130 °C, and pressed at 160 °C) were evaluated in terms of strain energy release rates (G _IC) during crack initiation and propagation. The results showed that specimens repaired by resin injection exhibited the highest G _IC values, about 30 % higher than the virgin state, due to the formation of a semi-interpenetrating polymer network (semi-IPN) at the joining interface. Scanning electron microscopy images provided insight into distinctive fracture behaviours for each test group.