GB697452A - Improvements in or relating to the production of emulsions of polyvinyl ester polymers - Google Patents

Abstract

Emulsions of a polymer of an ester of a monocarboxylic acid in which either the acid residue or the alcoholic residue contains a vinyl group are made by dispersing the ester in an aqueous medium comprising an alkali or amine salt of crotonic, fumaric, itaconic or maleic acid or of a monoester of fumaric, itaconic or maleic acid present in an amount not exceeding that derived from 5 per cent of the acid by weight of the vinyl ester, and heating the emulsion in the presence or absence of a percompound as catalyst, e.g. sodium persulphate. Optionally the aqueous media may contain one or more dispersing agents, emulsifying agents and plasticizers, e.g. dibutyl phthalate. If desired the salt, vinyl ester or catalyst may be added portionwise and the heating may be sufficient to cause no reflux or the heating may be effected under reflux with stirring. Vinyl esters specified are vinyl acetate, methyl and ethyl acrylates and mixtures. Dispersing and emulsifying agents mentioned are a copolymer of an ester of methacrylic acid, e.g. methyl, and an alkali metal salt of methacrylic acid, e.g. sodium, potassium, lithium, a sodium salt of an alkyl benzene sulphonic acid, e.g. sodium salt of dodecyl-toluene sulphonic acid, the sodium salt of dioctyl-sulphosuccinic acid, sodium dibutyl naphthalene sulphonate, the sodium salt of oleylated taurine, gums, e.g. gum arabic, dibutylphenyl phenol sodium disulphonate, polyalkyl aryl ether sulphate and sulphonate, the monolauric ester of triethanolamine, the monolauric ester of pentaerythritol, glyceryl monostearate and the lauric ester of a polyethylene oxide of molecular weight about 400. The amine may be triethylamine or diethylaminoethanol. Films may be made from the emulsions. The emulsions may also be mixed with pigments and cements. Specifications 627,612 and 648,001 are referred to.