a wide range of monomers commonly used in suspension and emulsion polymerisation for example one or more of the monomers selected from the group of the c 1 c 12 preferably the c 1 c 4 alkyl acrylates and methacrylates meth allyl acrylates and methacrylates butyl methacrylate stearyl methacrylate methacrylic acid methoxyproply methacrylate cyclohexyl methacrylate benzyl methacrylate hydroxyethyl methacrylate hydroxypropyl methacrylate dimethylaminoethyl methacrylate n butoxymethyl methacrylamide n butoxymethyl acrylamide glycidyl methacrylate vinyl acetate vinyl propionate styrene and vinyl styrene vinyl toluene methoxy styrene and vinyl pyridine di butyl maleate and vinyl chloride the known techniques of suspension and emulsion polymerisation including the selection of appropriate polymerisation initiators are applicable to the preparation of the aqueous dispersions of this invention as is understood in the art polar monomers may need to be used in combination with less polar monomers to achieve suitable aqueous polymeric dispersions either thermally activated or redox initiators may be used due to the reactivity of the compounds of formula i they have been found to provide a particularly stable dispersion of polymer particles therefore providing a significant improvement in aqueous coating compositions the aqueous dispersion may comprise additives which adapt it for use as a coating composition coating compositions may be prepared by blending standard additives such as pigments extenders antifoams thickeners and fungicides into the dispersion in art recognized quantities using known methods an example of polymer particles which.