MALEATED POLYISOBUTYLENE - A NOVEL TOUGHENER FOR UNSATURATED POLYESTER RESINS

A polyisobutene rubber was modified by grafting succinic anhydride ont o its end groups and has been used as a toughening agent for an unsatu rated polyester resin. Both the functionalization and the successive r eaction between the modified rubber and the polyester was investigated by Fourier transform infrared spectroscopy (FTIR). The yield behavior of the cured resins was studied by compression measurements, while th e fracture properties were determined at low and high strain rate. A m orphological analysis of the investigated blends has been carried out by scanning electron microscopy (SEM). A considerable enhancement of t ougheness has been achieved when the modified rubber was used in place of the plain polyisobutene. The effect was found to depend on the gra fting degree of the rubber and on the time period during which the two -component mixture was allowed to react prior to the curing process. ( C) 1995 John Wiley & Sons, Inc.