Effect of SiC whisker on benzoxazine-epoxy-phenolic ternary systems: Microwave curing and thermomechanical characteristics

Microwave radiation at 2.45 GHz with variable power input was investigated as a tool to facilitate the curing reaction of benzoxazine-epoxy-phenolic molding compound i.e., BEP893. Dielectric filler for microwave coupling was silicon carbide whisker (SiCw). Factors such as whisker loading and input irradiation power were found to have a profound effect on the microwave heating of the BEP893 particularly on the rate of temperature rise and maximum heating temperature. The SiCw loading of 10% by weight with the microwave irradiation condition of 300 W for 10 min renders the ultimate curing of the molding compound. Significant reduction in processing time of the microwave cured sample compared with the conventional heat cured sample i.e., 150 min at 200 degrees C using conventional heating is the key benefit of this technique. Mechanical properties of the microwave cured and conventional heat cured samples show similar characteristics with slightly lower T-g in the microwave cured samples. (c) 2007 Wiley Periodicals, Inc.