Study Of Synthesize Large Particle Size Latex With One-step Emulsion Polymerization

Large particle size polymer (n-butyl acrylate)(PBA) latex were prepared by one-step emulsion polymerization. The effect of monomer feedcontent, co-monomer composition (BA/St) and emulsifier type, on the resulting of monomer conversion rate, particle size and surface tension was studied.Two different complex emulsifier were used in the emulsion polymerization of n-butyl acrylate. By changing the ratio of adding material, large particle size PBA latex was synthesized in high solid content system. With the increase of solid content, monomer conversion rate increasing, and appropriate electrolyte’s adding is great benefit to the forming of large particles, moreover, surface tension decrease obviously.A series of poly (butyl acrylate-styrene) with different composition and solid content were prepared on the basic of butyl acrylate homopolymerization, the change of particle diameter and surface tension were investigated. The result showed that, particle size decrease and surface tension increase distinctly even lead to demulsification with increasing St concentration.Complex emulsifier was replaced by SDS, a series of PBA latex were prepared with different solid content and different emulsifier concentration under the adding of electrolyte. Final particle diameter shows that the diameter increase with the decreasing of emulsifier concentration, and it was more obviously on high solid content. In the same time, the latex which particle size higher than300nm was obtained on60%solid content, electrolyte can made latex more stability.