热处理对高硅氧织物增强甲基硅树脂复合材料室温弯曲强度的影响

研究了不同热处理温度对高硅氧织物增强甲基硅树脂复合材料室温弯曲强度的影响。结果表明,复合材料室温弯曲强度随着热处理温度的升高而降低,且在200~300℃、400~500℃分别出现了2个降低最快的温度区间。采用扫描电镜对复合材料弯曲断口的表面形貌进行了观察,并通过热重分析仪分别对基体树脂及增强体的热稳定性进行了测量。综合分析结果表明,当热处理温度低于400℃时,复合材料弯曲强度的降低主要是由于基体树脂与增强体之间的界面失效所致;而当热处理温度高于400℃时,增强体与树脂之间发生反应,导致增强体失效,是致使复合材料室温弯曲性能进一步下降的主要原因。

Influence of heat treatment on room temperature flexural strength of vycor glass cloth/methyl silicone resin composites

The effect of heat treatment on room temperature flexural strength of vycor glass cloth/methyl silicone composites was studied. The results show that the room temperature flexural strength decrease with the increasing of the heat-treated temperature, and there exist two dramatical decrease zones between 200 ℃ to 300 ℃ and 400 ℃ to 500 ℃. The morphologies of the flexural fracture sudaces of composites after different temperature heat-treated were characterized by using SEM, and the thermostability of the matrix and reinforcement were investigated by using thermogravimetry. The results show that the decrease of room temperature flexural strength of composites are caused by the failure of interface between the matrix and reinforcement when the heat-treated tem-perature is lower than 400 ℃ ; while when the heat-treated temperature is higher than 400 ℃, the fiber fracture which caused by the reaction between the matrix and reinforcement in composites becomes another reason to make the further decreasing of the room tem-perature flexural strength of composites.