| 摘要 |
PURPOSE: Provided are emulsions containing silicone particles in which the emulsion is prepared by first emulsifying organosilicon oligomers, and then polymerizing the emulsified larger particles of oligomers to a siloxane polymer of higher viscosity and/or higher molecular weight using a condensation specific acid catalyst. CONSTITUTION: The emulsion containing particles of an organopolysiloxane is prepared by (i) combining a silanol endblocked siloxane, an alkyltrialkoxysilane, water, and a nonionic surfactant or an anionic surfactant; (ii) emulsifying these ingredients by agitating these ingredients or by using a high shear device; (iii) adding a condensation specific acid catalyst to the emulsion; (iv) polymerizing the catalyzed emulsion to form an organopolysiloxane polymer; and (v) continuing polymerizing step (iv) until the resulting organosiloxane polymer has the desired viscosity. Organosiloxane polymers exhibiting improved release properties can be obtained by using alkyltrialkoxysilanes R'Si(OR'')3 where R' and R'' each represent alkyl groups, and R' contains at least eight, preferably at least twelve, and most preferably at least sixteen or more carbon atoms.
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