Studies on Thermal and Mechanical Properties of Glass Fiber-Reinforced Unsaturated Polyester/Benzoxazine Composites

Unsaturated polyester/benzoxazine copolymer was employed to prepare polyester/benzoxazine/glass fiber composite laminates and their mechanical, morphological, and thermal properties were investigated. Compared with those of 100UPR/0PBZ/10GF composites, the tensile strength and flexural strength of 90UPR/10PBZ/10GF composites with 10 wt % polybenzoxazine content were increased by 10 % and 6 %, respectively. The enhancements in mechanical properties are mainly due to the strong interfacial adhesions between glass fiber and UPR/PBZ matrices, which were confirm by the SEM images of fracture surfaces of the composites. Curing behavior of glass fiber filed composite was investigated by differential scanning calorimetry analysis. All UPR/PBZ/GF composite laminates are thermally stable up to 270 0C in air. Furthermore, TGA thermograms revealed that the degradation temperatures of UPR/PBZ/GF composite increased with compare UPR/GF composite. UPR/PBZ/GF composite laminates will have potential applications in the areas where require of excellent mechanical properties and high temperature resistance.