Synthesis of Acrylic Emulsion Containing High Hydroxyl Content

Using butyl acrylate (BA), methyl methacrylate (MMA), acrylic acid (AA), and hydroxylethyl methacrylate as comonomers, along with ammonium persulfate as initiator, emulsions with high hydroxyl content (10-35%) and carboxyl groups were synthesized from semi-continuous seed emulsion polymerization methods. Emulsifier types and levels, reaction temperature, level of hydroxyl monomer, and level of monomer carboxyl on stability of the emulsion polymerizations were investigated. Viscosity of the emulsion was discussed. It was found that when the sodium lauryl sulfate (SLS) and p-octyl polyethylene glycol phenyl ether (OP) mixed emulsifiers were used, at a level of 3%, and a ratio of SLS/OP of 4/6, along with a reaction temperature at 65-75°C, the polymerization process had lower coagulum. As the levels of hydroxyl monomer and carboxyl monomer increased, the coagulum increased, and the viscosity of the resulting emulsion.