Latex particles with core-shell structure of polybutyl acrylate (PBA)/casein (CA) were prepared through emulsion polymerization of BA in the presence of CA without any surfactant and with tert-butyl hydroper oxide (TBHP) as the initiator. Influences of polymerization temperature, initiator amount and ratio of BA/CA on monomer conversion, PBA grafting and particles size etc. were studied. The preparation process for PBA/CA core/shell particles was optimized, and the mechanisms of particle formation were discussed.

Key words: casein, butyl acrylate, redox initiation, graft polymer, core-shell latex particle