First synthesized silver specific molecular structure of silicone oil. And then treated with silicone oil made of allyl polyether addition prepare a polyether-modified silicone antifoam via hydrosilylation under a temperature condition of 130 ℃. By standard defoamer structure showed that: when the reaction was n (C = C) :n ( Si-H) = 1:1; mass fraction of the catalyst was 0.002%, the resulting polyether-modified silicone elimination foaming agent has a very prominent defoaming properties in aqueous emulsion paints. Currently, polyether defoamers mainly used for high system compatibility requirements, anti-foaming capability is weak, less market share. Modified polyether segment; silicon-based antifoaming agent and the defoaming capacity increase complex; widening of the scope of application; oil-soluble or water-soluble polyether and a silicon-containing polyether compound defoamer technology is the study of the class direction