In a high grade monodispersed latices of not - film-forming polymers and process for their preparation

摘要

1488554 Latexes of narrow particle size distribution DOW CHEMICAL CO 6 June 1975 [10 June 1974 17 June 1974 29 Aug 1974] 24459/75 Heading C3P A water-insoluble copolymer of an emulsion polymerizable, ,#-ethylenically unsaturated hard (non-film-forming) monomer and at least 1 weight per cent of an emulsion polymerizable, ,#-ethylenically unsaturated amide in the form of non-film forming discrete particles having an average particle diameter in the range from 0À25 to 1 micrometer with no more than 10 weight per cent of the particles having diameters outside that range may be prepared in the form of a highly monodisperse latex by (1) dispersing the hard monomer and the amide in an aqueous phase containing surfactant in an amount which is from 0À1 to 0À90 of the critical micelle concentration of the surfactant, the hard monomer being inert to the amide and the proportion of amide to hard monomer being sufficient to provide a water-insoluble copolymer containing at least 1 weight per cent of the amide; and (2) subjecting the dispersion to emulsion polymerization conditions such that at least a stabilizing amount of the amide is present in the aqueous phase during polymerization. The polymerization can be carried out as a seed polymerization process or by the addition of one or more of the monomers during polymerization.