含氢氟硅油对加成型氟硅橡胶性能的影响

摘要

以四甲基环四硅氧烷 (DH4) 、三氟丙基甲基环三硅氧烷 (DF3) 、四甲基二硅氧烷为原料, 磺酸树脂球为催化剂, 合成了不同活性氢质量分数的含氢氟硅油, 再将其与端乙烯基或侧乙烯基氟硅液体胶进行加成反应, 考察了含氢氟硅油活性氢质量分数和用量对加成型氟硅橡胶性能的影响.结果表明, 当含氢氟硅油用量一定时, 随着活性氢质量分数的提高, 端乙烯基氟硅橡胶硬度升高, 拉伸强度先增后减, 拉断伸长率减小;当活性氢质量分数一定时, 随着含氢氟硅油用量的增加, 端乙烯基氟硅橡胶硬度和拉伸强度降低, 拉断伸长率提高;当活性氢质量分数为0.3％, n (Si—H) ∶n (Si—Vi) =3.5时, 端乙烯基氟硅橡胶邵尔A硬度为40度, 拉伸强度为6.4 MPa, 拉断伸长率为589％.%The hydrofluorosilicone oil with different mass fraction of the active hydrogen was synthesized by trifluoropropylmethylcyclotrisiloxane and tetramethylcyclotetrasiloxane as the raw materials, tetramethyldisiloxane as the capping agent, sulfonic acid resin as the catalyst.Then the addition reaction was carried out with vinyl-terminated or side-vinyl fluorosilicone rubber.Effect of active hydrogen content and amount of hydrofluorosilicone oil on the properties of additive fluorosilicone rubber was investigated.Results show that when the content of hydrofluoro silicone oil is constant, with the increasing active hydrogen mass fraction of the fluorosilicone rubber, the hardness of the vinyl-terminated fluorosilicone rubber increases, whose tensile strength increases at first and then decreases.When the active hydrogen mass fraction was constant, with the increasing amount of hydrofluoro silicone oil, the hardness and tensile strength of vinyl-terminated fluorosilicone rubber decreases, but its elongation at break increases.When the content of active hydrogen is 0.3％, n (Si—H) ∶n (Si—Vi) =3.5, the content of active hydrogen is 0.3％, the Shore A hardness of vinyl-terminated fluorosilicone rubber is 40 degree, while the tensile strength is 6.4 MPa, the elongation at break is 58.9％.