填料改性低黏度耐高温硅橡胶胶粘剂的制备与性能研究  

Preparation and properties of filler modified low viscosity and high-temperature resistance silicone rubber adhesive

作　　者：李然 郭安儒[1] 胡杰[1] Li Ran;Guo Anru;Hu Jie(Aerospace Research Institute of Materials&Processing Technology,Beijing 100076,China)

机构地区：[1]航天材料及工艺研究所,北京100076

出　　处：《中国胶粘剂》2024年第12期38-44,共7页China Adhesives

摘　　要：针对硅橡胶胶粘剂高温烧蚀环境的使用性能和工艺性需求,合成了低黏度的苯基硅橡胶基础胶,并表征基础胶分子量分布、苯基含量和黏度。所制备的基础胶苯基含量22.5%~23.8%,黏度6530~11500mPa·s,挥发分0.30%~0.37%,说明基础胶的黏度和挥发分均处于较低水平,具有良好的工艺性。然后采用苯基硅橡胶基础胶与白炭黑、铁红、短切碳纤维混炼,制备室温硫化硅橡胶胶粘剂。采用三因素三水平正交试验考察了无机填料对硅橡胶胶粘剂黏度、拉剪强度、耐温性能的影响。研究结果表明:(1)从黏度和拉剪强度的极差分析可以看出,对黏度影响最大的为白炭黑,其次为短切碳纤维。添加白炭黑,会使拉剪强度与黏度同时增加,因此在黏度许可的范围内,提高白炭黑用量,可以提高拉剪强度。(2)对残碳率进行极差分析,铁红对于残碳率的影响远大于白炭黑、短切碳纤维。铁红能够显著提高硅橡胶胶粘剂的热稳定性,当铁红添加量为10份时,加温过程中的鼓胀和排气被明显抑制。In response to the performance and process requirements of silicone rubber adhesive in high-temperature ablation environments,a low viscosity phenyl silicone rubber base adhesive was synthesized,and the molecular weight distribution,phenyl content,and viscosity of base adhesive were characterized.The prepared base adhesive had a phenyl content of 22.5%to 23.8%,a viscosity of 6530 to 11500 mPa·s,and a volatile content of 0.30%to 0.37%.This indicated that both the viscosity and volatile content of base adhesive were at a low level,which was conducive to good processability.Subsequently,the room temperature vulcanizing silicone rubber adhesive was prepared by mixing phenyl silicone rubber base adhesive with white carbon black,iron oxide red,and chopped carbon fiber.A three-factor,three-level orthogonal experiment was used to investigate the effects of inorganic fillers on the viscosity,tensile shear strength,and temperature resistance of silicone rubber adhesive.The research results showed that,(1)From the range analysis of viscosity and tensile shear strength,it could be seen that white carbon black had the greatest impact on viscosity,followed by chopped carbon fiber.Adding white carbon black would increase both tensile shear strength and viscosity.Therefore,within the allowable range of viscosity,increasing the amount of white carbon black could improve tensile shear strength.(2)The range analysis of residual carbon rate showed that iron oxide red had a much greater impact on residual carbon rate than white carbon black and chopped carbon fiber.Iron oxide red could significantly improve the thermal stability of silicone rubber adhesive.When the amount of iron oxide red added was 10 parts,the swelling and exhaust during the heating process were significantly suppressed.

关 键 词：苯基硅橡胶胶粘剂 填料 改性 白炭黑 铁红 短切碳纤维 耐高温 

分 类 号：TQ437[化学工程]