Abstract: In this paper, a modified phenolic resin was studied, including viscosity property, heat resistance and ablative property. It is found that the viscosity of resin system is lower than 800mPa·s in the range of 60~120℃, process applicable period is longer than 150 mins at 70℃ and 80℃. The glass transition temperature is 253℃, carbon residue rate at 800℃ is 67.1% in the Nitrogen atmosphere, quality ablation rate and linear ablation rate are 0.0766g/s and 0.119mm/s. Carbon fiber needling preform reinforced the modified phenolic resin composite was made by RTM, its interlayer shear strength and axial compressive strength are 39.3MPa and 177MPa, respectively. The linear ablation rate and quality ablation rate are 0.044mm/s and 0.0762g/s. Experimental results show that this modified phenolic resin system, which has low viscosity, long process applicable period, good heat resistance and ablative property, can meet the requirement of RTM process well, and its carbon fiber needling perform composite has the potential of being used as ablation resistant material.

Key words: modified phenolic resin, RTM process, viscosity property, ablative property