PREPARATION METHOD OF ULTRAFINE SILOXANE REACTION POLYMER

摘要

PURPOSE: An ultrafine siloxane reaction polymer, its preparation method and a paint prepared from the polymer are provided, to improve intermolecular binding force, blending stability and water dispersibility of a siloxane reaction polymer. CONSTITUTION: The method comprises the steps of (I) dissolving a siloxane resin intermediate(A1) in a protic solvent(A2) to prepare a siloxane resin protic solution(A); (II) adding a linear polysiloxane(B) to the solution and heating it to adhere the siloxane resin intermediate to the linear polysiloxane particle; (III) adding a metallic base(C) to the reaction mixture and heating it to open the siloxane chain of the siloxane resin intermediate and the linear polysiloxane and to crosslink it; and (V) adding a tin oxide-based condensation catalyst(D) to the reaction mixture to prepare an ultrafine siloxane reaction polymer by condensation. Preferably the siloxane resin intermediate is a methylsiloxane resin or methylphenylsiloxane resin; the protic solvent is diethylene glycol monobutylether or diethylene glycol monoethylether; the linear polysiloxane is selected from the group consisting of dimethyl polysiloxane, methylphenyl polysiloxane, diphenyl polysiloxane and a copolymer of siloxane and diphenylsiloxane; the metallic base is a NaOH or KOH aqueous solution; and the catalyst is at least one selected from the group consisting of dibutyl tin oxide, dibutyl tin dilaurate, dibutyl tin dicarboxylate, dibutyl tin bismercaptide and stannous octoate.