Adhesion between rubber-modified thermoplastics and a glass-reinforced polyester resin

Adhesion between some rubber-toughened thermoplastics and a glass-reinforced polyester resin directly applied on the former was studied in two ways. First the absorption of the uncatalyzed polyester prepolymer by the thermoplastic materials was evaluated, and adhesion strength was then characterized according to the fracture mechanics approach, using double cantilever beam joints to determine Mode I fracture toughness. The results of both absorption tests and fracture mechanics tests enable the authors to propose a mechanism for the adhesion between these materials, to define the optimum conditions (curing temperature and initiator content) for adhesion and to pinpoint the characteristics the thermoplastic materials ought to have in order to obtain a good joint.