The Synthesis Of Polyether Modified Silicone Emulsifier And Its Application In Defoamer

In this paper, polyether modified silicone emulsifiers with different HLB ranges were synthesized and were used to prepare for a variety of types of polyether modified silicone defoaming agent.Serializable polyether modified silicone emulsifiers with HLB from1.3to17.1was synthesized with hydrogen silicone oils with different hydrogen contents and allyl polyethers. Through the single factor experiment and orthogonal test, the optimal reaction conditions were obtained as follows:n(Si-H):n(C=C)=1:1.3; temperature120℃; reaction time6h; the amount of catalyst20ppm.Defoamer applied in water wooden color paint was prepared with polyether modified silicone and silicon paste and polyether compound. By studying the affecting factors of reaction and according to the results of inhibiting foam and its stability, the better prescription includes silicon paste5%; polyether modified silicone SA01830%; polyether4118or401030%.Defoamer applied in water wooden varnish were synthesized with lowmolecular hydrogen silicone and polyether compound P and A. By the single factor experiment, the optimization process conditions are:temperature130℃; reaction time5h; the amount of catalyst20ppm; n(Si-H):n(C=C)=1:1.1. The influence of D4content grafted in hydrogen silicone and the molar ratio of polyether P to polyether A on inhibiting foam has been discussed, the optimum prescription was determined as follows:n(hydrogen silicone Sg):n(D4)=1:1, n(polyether P):n(polyether A)=7:3.Emulsion defoamer applied in adhesive was obtained with polyether modified silicone emulsifiers with the different HLB by mixing and self-emulsifying. According to the results of inhibiting foam and its stability, it revealed that fixed inhibiting foam component m(SP018):m(SP024):m(SP050)=1:1:1, under these conditions of emulsification component m(SE018):m(SE024):m(SE050)=1:2:2; m(inhibitting foam component):m(emulsification component)=1:1; Mixed type of defoamer applied in adhesive was obtained, which was prepared by using siloxane mix with polyether. According to the results of brushing to defoamer and the test of inhibiting foam. A better data was as follows:polyether4010as polyether component; polyether modified silicone, which was synthesized with0.24%hydrogen silicone and polyether P and A.as siloxane component,including the mole ratio of polyether P and polyether A was4:6; the mass ratio of siloxane component and polyether component was3:7.On the basis of researching of the import emulsifier, the stable emulsion of silicone defoamer was prepared, which was emulsified with three kinds of self-made polyether modified silicone emulsions. By studying the affecting factors on stability of emulsion, A better conclusion was:the three kinds of self-made emulsifiers were SDA018, SY050and SP018,and the compound HLB value is9.6; the amount of emulsifier is6%;the amount of thichener is3%. Compared with the above three kinds of emulsifier, The compound emulsifier made through blending SDA018and SP018compound, emulsion stability is greatly improved.