Research on Copolymerization of Polysiloxane/Acrylates Soap-free Emulsion

The soap-free organosiloxane modified acrylats emulsion was prepared by using sodium p-styrene sulfonate(NaSS)and β-hydroxyl ethyl methacrylate(HEMA)as ionic and nonionic functional monomer and K2S2O8 as initiator.The effects of the reaction conditions,such as the reaction temperature,the amount and ratio of the functional monomers,etc,and the adding order of organosiloxane on the emulsion polymerization and the property of the emulsion were investigated systematically.The study found that a stable polyacrylates emulsion was obtained with the addition of 0.4% of functional monomer(NaSS:HEMA=3:1)and adopted seeded emulsion polymerization techniques at 78～80,℃.The study showed that there was a lot of gelatin after the addition of organosiloxane.A stable organosiloxane modified acrylates emulsion can be obtained whether the organosiloxane was added in the beginning or at the end using NaSS/HEMA as functional monomer.The gel was easily produced at the stage of heat preservation.The polymerization stability was better when the organosilox-and was added in the end and initiated by multi-initiating system:first initiated by K2S2O8 and then initated by redox initia-tion system when the organosiloxane was added.