Process for preparing spherical and porous vinyl resin particles

A process for producing spherical particles of polymer having a high porosity which comprises polymerizing in an aqueous medium, in a reaction vessel having an agitator position therein, one or more ethylenically unsaturated monomers having a terminal CH.sub.2 .dbd.C<

• grouping in the form of discrete particles having a diameter in the range of about 30 microns to about 1000 microns, said aqueous medium containing a monomer-soluble free radical yielding catalyst, a dispersant comprising a substantially unneutralized, water-insoluble, cross-linked polymer of one or moe carboxylic acid monomers with a polyunsaturated crosslinking monomer havng a plurality of terminally unsaturated polymerizable groups, at least one non-polyethylene oxide containing surfactant selected from the group consisting of the sorbitan ester family, glycerol ester family, and polyglycerol ester family, and at least one polyethylene oxide containing surfactant selected from the group consisting of polyoxyethylene alkylphenols, polyoxyethylene alcohols, polyoxyethylene esters of fatty acids, polyoxyethylene alkylamines, and polyoxyethylene alkylamides and polyoxyethylene sorbitan ester, conducting the polymerization at a temperature in the range of about 0.degree. C. to about 150.degree. C. with vigorous agitation in said aqueous medium throughout the entire polymerization reaction.