聚醚改性硅油乳化剂的合成及其在特种有机硅消泡剂中的应用

Synthesis of Polyether Modified Silicone Oil Emulsifier and its Application as Special Silicone Defoaming Agent

以端烯丙基聚醚F6、含氢硅油为原料,氯铂酸为催化剂,甲苯为溶剂,合成出聚醚改性硅油(PMS),并用红外光谱对其结构进行表征。正交实验优化合成条件为:原料中Si—H与CC的量之比为1∶1.2,催化剂用量为30×10-6,反应温度100℃,甲苯质量分数30%,该条件下反应3 h,含氢硅油中Si—H的转化率达98.7%。将其与白炭黑、甲基硅油等复配,制得粒径小、分布范围窄、球状颗粒的消泡剂。该乳液在65℃下贮存稳定,在高温、不同pH值(2～13)条件下不分层、不漂油,且能保持消泡速度快、抑泡活性强的特点。在PMS用量为起泡液质量的0.06%,鼓泡速度为3.0 L/min条件下,消泡剂可在5.5 s内使高度为500 mL的泡沫迅速破裂,抑泡时间长达1 510 s。

Polyether modified silicon surfactant（PMS） was synthesized with allyl endcapped polyoxyethylene polyoxypropylene ether（PE） and（PHMS） as the raw materials,H2PtCl6 isopropyl alcohol as the catalyst and toluene as the solvent.The optimal experimental conditions for synthesizing PMS were obtained through orthogonal test： the reaction was carried out at 100 ℃ for 3 h with a molar ratio of m（PE）/m（PHMS）=1.2,30 ppm of H2PtCl6 catalyst,30 wt% of toluene.Under such circumstances,PHMS conversion reached 98.7%.The properties of PMS were characterized by FT-IR spectroscopy,fluorescence microscopy,and laser particle size analyzer.PMS synergized with other emulsifier was endowed with good emulsifying capacity for preparing stable silicone defoamer emulsion with no delamination and emulsion breaking under different acid-base condition（pH value of 2-13） and at high temperature.Moreover,the particle size distribution of the silicone defoamer showed much smaller particle size（16.2 μm） with narrower size distribution and more regular shape,and excellent defoaming and foam suppression properties to sodium dodecyl-sulphonate foamer system,compared with that without PMS.When PMS was 0.06% of the foam liquid,and the bubble speed 3.0 L/min,the defoamer made the collapse of 500 mL bubbles in 5.5 seconds,with foam depressing long as 1510 seconds.