presence of alkali metal acetates alkali metal carbonates or alkali metal phosphates polymerization regulators like mercaptan aldehydes chloroform ethylene chloride and trichloroethylene can also be added when needed the emulsifying agents used in the polymerization can be any of those generally known and used in emulsion polymerizations suitable emulsifying agents are anionic cationic or nonionic emulsifiers or surfactants or mixtures of them examples of suitable anionic emulsifiers are alkyl sulfonates alkylaryl sulfonates alkyl sulfates sulfates of hydroxyalkanols alkyl and alkylaryl disulfonates sulfonated fatty acids sulfates and phosphates of polyethoxylated alkanols and alkylphenols and esters of sulfosuccinic acid examples of suitable cationic emulsifiers are alkyl quaternary ammonium salts and alkyl quaternary phosphonium salts examples of suitable nonionic emulsifiers are the addition products of 5 to 50 moles of ethylene oxide adducted to straight chain and branched chain alkanols with 6 to 22 carbon atoms or alkylphenols or higher fatty acids or higher fatty acid amides or primary and secondary higher alkylamines and block copolymers of propylene oxide with ethylene oxide combinations of these emulsifying agents may also be used in which case it is advantageous to use a relatively hydrophobic emulsifying agent is in combination with a relatively hydrophilic agent the amount of emulsifying agent is generally from about 1 to 10 preferably from about 2 to 8 by weight of the monomers used in the polymerization various protective colloids may also be used in place of or in addition to the emulsifiers described above suitable colloids include.