再生硅橡胶/甲基乙烯基硅橡胶共混物的性能

Properties of recycled silicone rubber/methyl vinyl silicone rubber blends

采用机械剪切破碎法制备再生硅橡胶,并将其掺入到甲基乙烯基硅橡胶中制备再生硅橡胶/硅橡胶共混物,研究了再生硅橡胶含量、硫化促进剂2,5-双(叔丁基过氧化)-2,5-二甲基己烷和沉淀法白炭黑用量对共混物硫化特性和力学性能的影响,通过傅里叶变换红外光谱、动态力学分析仪和扫描电子显微镜对共混物和硅橡胶进行了分析。结果表明,随着共混物中再生硅橡胶含量的增加,共混物的硫化速率变慢,力学性能降低,当再生硅橡胶质量分数为46.9%时,共混物的综合力学性能较好。当2,5-双(叔丁基过氧化)-2,5-二甲基己烷用量为0.5份(质量)且沉淀法白炭黑用量为15份时,共混物具有良好的力学性能。机械剪切破碎法没有引起再生硅橡胶化学性质的变化;共混物的玻璃化转变温度与硅橡胶接近,但其损耗因子峰值下降;共混物中填料的分散均匀性介于再生硅橡胶与硅橡胶之间。

Recycled silicone rubber was prepared by me- chanical shearing, which was added into methyl vinyl silicone rubber （MVQ） to prepare recycled silicone rubber/MYQ blends, the effect of recycled silicone rubber content, cure ac- celarator 2,5-bis-（ tert-butyl peroxy） -2,5-dimethyl hexane and precipitated silica amount on the curing behavior and mechani- cal properties of the blends was investigated, the blends and MVQ were characterized by Fourier transform-infrared spec- troscopy, dynamic mechanical analysis and scanning electron microscopy. The results showed that the curing speed of the blends became slower and the mechanical properties of the blends decreased with the increase of recycled silicone rubber content. When recycled silicone rubber content was 46. 9% , 2,5-bis-（ tert-butyl peroxy）-2, 5-dimethyl hexane was 0. 50 phr, and precipitated silica was 15 phr, the blends had better mechanical properties. The recycled silicone rubber had no change in chemical character by mechanical shearing, the glass transition temperature of the blends was similar to that of MVQ, but its loss factor peak declined, and filler dispersion in the blends was between MVQ and recycled silicone rubber.