Research of Modificating Unsaturated Polyester Resinby Copolymerizing Bismaleimide

The modification of an unsaturated polyester(UP) resin by copolymering a second co-reactive monomer as thermosetting bismaleimide(BMI) was studied. The resulting inter-crosslinked network showed an obvious enchancement of the glass transition temperature ,elastic modulus and strength. FTIR is used to investigate the c=c double bond conversion of the various reactive species in the copolymerization.The conversions are 70.83%,95.64% and 97.69%for UP resin ,styrene and BMI respectively.It was shown that BMI is strongly accelerated in the curing reaction of the UP resin. SEM analysis performed on the fracture surface of the various investigated resin system showed that there was no evidence of phase seperation.