abstract |
Dry monodispersed polymeric particles, a stabilized dispersion of such and a method for making are described. The dispersion comprises a polar dispersion medium having dispersed therein monodispersed particles comprising a thermoplastic resin core substantially insoluble in the dispersion medium formed from a styrene or butylmethacrylate containing monomer or mixtures thereof and having irreversibly anchored thereto, a nonionic amphipathic steric stabilizer comprising a graft copolymer having a portion formed from a styrene or butylmethacrylate containing monomer or mixture thereof and a portion formed from hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxybutyl methyl cellulose, hydroxypropyl methyl cellulose, ethyl cellulose or cellulose propionate. The stable dispersion is made by dissolving the nonionic cellulose ether in the polar dispersion medium and in the presence of a free radical initiator adding styrene or butylmethacrylate containing monomer a mixture thereof thereto, and permitting polymerization to take place. |