Preparation and Mechanical Properties of New Types Unsaturated Poly(ester-imide) Resin Composites

Novel bis-(carboxyphthalimide)s as unsaturated polyester resin raw material were synthesized with 4,4′-diaminodiphenylsulfone, 4,4′-diaminodiphenylmethane, and 4,4′-dianminodiphenylrther named BSI, BTI, BEI, respectively, and then a series of resins containing imide groups were synthesized. The poly(ester-imide) resin composites were prepared by molding technology, and the effect of imides on mechanical properties such as impact strength, flexural strength, and wear resistance were investigated. Microstructure was characterized by means of scanning electron microscopy (SEM). The dynamic mechanical analysis (DMA) indicates that storage modulus of hybrid composites increase significantly because of the addition of the bis-(carboxyphthalimide)s. The composites containing BTI give the optimal flexural strength 86.17 MPa, and the wear volume of composites containing BEI is 2.82 mm³. SEM micrographs of impact fractured and worn surfaces clearly demonstrate the interfacial adhesion between fibre and resin. The results show that thermal stabilities of the composites are improved significantly, but the mechanical properties are affected slightly due to the introduction of rigid imide groups into the polyester chain.