Preparation Of Nano-Sized Hollow Latex Particles

Nano-sized hollow latex particles were prepared by alkali swelling method. Firstly the carboxylated nano-core particles were prepared by using methyl methacrylate, methylic acid and divinyl benzene as comonomers. And then methyl methacrylate, butyl acrylate styrene and divinyl benzene were copolymerized to form the shell layers with high glass transition temperature onto the core particles. Finally, the alkali treatment was carried out to the core-shell latex particles to obtain the hollow particles with the size of about 120 nm.In the present work, the effects of the feeding strategies for the monomers, emulsifier and initiator, the dosage of methacrylic acid, emulsifier and crosslinking agent, the shell monomers composition, agitation and polymerization temperature on the particles and their distribution, the emulsion stability and the hollow structure of the particles were investigated. The optimized technology for preparing the nano-sized hollow latex particles was obtained.The hollow structure of the particles was characterized with TEM, and DLS and TEM were used to measure the particle size and its distribution. While the content of methacrylic acid was 10mass% to the core monomers, and the dosages of sodium dedecane suflfate were 3.0mass% and 0.3mass% to the monomers in the core and shell stage, respectively, and the mass ratio of the core monomer to shell monomer was 1:6, the particles prepared could be hollow-structured and monodispersed.