| Seeded emulsion polymerization was adopted to prepare hollow latex particles with moderate size and enough rigidity. Methyl methacrylate/butyl acrylate/methacrylic acid copolymer emulsions were first prepared as seed latexes and the seeded emulsion polymerizations of methyl methacrylate, methylacrylic acid (MAA) and divinyl benzene (DVB) were carried out to prepare hydrophilic carboxylated core latex particles consequently. The hydrophobic shell was then formed on the basis of the core by using styrene, acrylonitrile and divinyl benzene as comonomers. Finally, the hollow latex particles were obtained by alkalization treatment of the core-shell latex particles. The effects of stirring rate, reaction temperature, dosages and feeding methods of MAA and sodium dodecyl benzene sulfonate (SDBS), DVB content, ratio of the core monomers to shell ones, reaction time, temperature and initial pH for alkalizng on the stability of the emulsion system, as well as sizes, morphologies and volume expansions of hollow latex particles were investigated. The morphologies and particle sizes of hollow latex particles were characterized by TEM and nanosizer. The results show that the hollow latex particles with largest volume expansion can be obtained when MAA content is 30%(wt), SDBS contents are 0.15wt% and 0.2wt% respectively during the core and shell stage, and the monomer ratio of core to shell layer is 1:8.
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