硬脂酸锌脱模剂对HTV硅橡胶性能的影响  

Effect on Properties of HTV Silicone Rubber by Zinc Stearate

作　　者：詹学贵[1] 周汴香[1] 蔡含宙[1] 胡盛[1] 

机构地区：[1]浙江新安化工集团股份有限公司,浙江建德311600

出　　处：《有机硅材料》2014年第2期100-104,共5页Silicone Material

摘　　要：以硬脂酸锌为脱模剂、聚甲基乙烯基硅氧烷为基胶、气相法白炭黑为填料，制备了通用型热硫化（HTV）硅橡胶（简称气相胶）。研究了硬脂酸锌用量对气相胶力学性能、回弹及压缩性能、硫化性能、热稳定性能、脱模性能及二次抗黄变性能的影响。结果表明：随着硬脂酸锌用量的增加，气相胶的邵尔A硬度逐渐降低，拉断伸长率略有增加，撕裂强度减少，二次回弹降低，压缩永久变形值降低，硫化速度降低，高温下的硬度和回弹降低明显，二次抗黄变性能逐渐变差。因此在进行通用型气相胶配方设计的时候硬脂酸锌脱模剂的用量应控制在0．05—0．20份之间，最佳用量为0．10～O．15份，此时，气相胶的一次硫化后的邵尔A硬度为49．5—47．5度，拉断伸长率为520．0％～540．0％，撕裂强度为30．55—30．33kN／m，一次回弹为70．0％～70．5％；二次回弹为65．5％一68．0％，175℃×22h（25％压缩比）压缩永久变形为36．0％～40．2％，MI值为0．571～0．569N·m，MH值为10．556～10．217N·m，t10为30．05～30．23S，t50为50．57～51．88S，t∞为107．63～108．58s，一次硫化与250℃×2h老化后硬度差为6．0—9．5度，回弹差为21．O％～29．0％。General HTV silicone rubber was prepared with zinc stearate as the release agent, polymethyl- vinylsiloxane as gum and fumed silica as a filler. The effect on mechanical properties, resilience, compression set, vulcanization properties, thermal stability, release property and yellowing resistance after post-cure of silicone rubber by different amounts of zinc stearate were studied. Results showed that if the amount of zinc stea- rate increased, the shore hardness,＇ tear strength, resilience after post-cure and the value of compression set decreased, the yellowing resistance after post-cure got worse and the vulcanization rate of the rubber was slower. At high temperature, the shore A hardness and resilience of silicone rubber compound decreased more obviously. However, the elongation at break slightly increased and the release property became better. When the amount of zinc stearate was between 0. 05 phr to 0.20 phr, 0. 10 phr to 0. 15 phr was optimal. The shore hardness of the silicone rubber was 49.5 to 47.5, the elongation at break was 520% to 540%, the tear strength was 30. 55 kN/m to 30.33 kN/m, the resilience was 70. 0% to 70. 5%, the resilience after post-cure was 65.5% to 68.0%, the value of compression set was 36.0% to 40.2% %, after the experiment condition of 175 % × 22 h （25 % compression ratio）, the value of ML was 0. 571 N. m to 0. 569 N. m, the value of MH was 10. 556N-m to 10. 217 N.m, tl0 was 30. 05s to 30.23s, ts0 was 50. 5% to 51.88s, and tgo was 107.63s to 108.58s. The hardness difference in the aging process between one-step curing and 250℃ × 2 h was 6.0A to 9.5A, whose resilience was 21.0% to 29.0%.

关 键 词：硬脂酸锌 回弹 热稳定性 脱模性 热硫化 硅橡胶 气相法白炭黑 

分 类 号：TQ333.93[化学工程—橡胶工业]