长链烷基改性硅油的制备、表征与性能研究

Preparation,characterization and properties of long chain alkyl modified silicone oil

采用无溶剂硅氢加成法,以1-辛烯、1-十二烯、1-十六烯、含氢硅油为原料,氯铂酸为催化剂,制备长链烷基改性硅油。产物的结构采用FTIR和1 H-NMR进行表征。通过正交试验和单因素实验,研究了反应温度、反应时间、催化剂用量、n(Si—H)∶n(C C)对Si—H转化率的影响,确定了产物的最佳合成工艺。研究了不同烷基摩尔质量比和烷基长度对产物的黏度指数、表面张力、润滑性能、折光率的影响。结果表明:在优化工艺条件(n(Si—H)∶n(C C)=1∶1.2,反应时间6 h,反应温度100℃,十二烯活化催化剂用量3 mg/L)下,产物的Si—H转化率高达92.6%;随着烷基摩尔质量比和烷基长度的增加,硅油的黏度指数逐渐下降至358,从而降低了硅油的黏温性能,但其表面张力变化不大。改性后的硅油的润滑性能和折光率得到了显著提升,其磨斑直径最小为0.33 mm,折光率最大值为1.4396。

Long-chain alkyl modified silicone oil was prepared by solvent-free hydrosilylation reactionusing 1-octene,1-dodecene,1-hexadecene with hydrogen-containing silicone oil as raw materials and chloroplatinicacid as catalyst.The structure of the product was characterized by FTIR and 1 H-NMR.Through orthogonal and single factor experiments,the effects of reaction temperature,time,amount of catalyst and n(Si—H)∶n(C C)on Si—H conversion rate were studied.The results showed that under the optimized process conditions(n(Si—H)∶n(C C)=1∶1.2,reaction time 8 h,reaction temperature 100℃,dodecene activation catalyst dosage 3 mg/L),the Si—H conversion rate of the product reached to 92.6%.Further,with optimized condition,we found that with the increase of alkyl content and alkyl length,the viscosity index of silicone oil decreases gradually(as low as 358),which reduces the viscose-temperature property of silicone oil,but has little effect on its surface tension.The lubrication performance and refractive index of the modified silicone oil have been significantly improved,with the minimum spot diameter of 0.33 mm and the maximum refractive index of 1.4396.