A method for the preparation of stable emulsions of copolymers of maleic ethylenediaminopolypropylene lens

摘要

Stable aqueous emulsions of ethylene copolymers are prepared by polymerizing ethylene in aqueous medium at a pH of 4 to 8 in the absence of conventional emulsifiers, under elevated pressure and in the presence of a water-soluble radical forming catalyst, in the presence of 50 to 70 weight per cent of vinyl chloride and 2 to 10 weight per cent of a semi-ester of maleic acid and an aliphatic monohydric alcohol containing up to 6 carbon atoms in the alcohol residue, or a salt of such a semi-ester. The semi-ester may be derived from propanol, butanol, pentanol, hexanol or cyclohexanol, and specified salts are the alkali metal and ammonium salts. Specified catalysts are potassium, sodium and ammonium persulphates, perborates and hydrogen peroxide, and mixtures thereof with reducing agents, e.g. sodium pyrosulphite, sodium metabisulphite, sodium formaldehyde sulphoxylate and triethanolamine. The medium may also contain buffers, e.g. primary and secondary potassium phosphates, and organic solvents, e.g. t.-butanol. Examples describe the preparation of stable emulsions by copolymerizing ethylene and vinyl chloride with (1, 2, 7 and 8) monopropyl maleate, (3) mono-ethyl, (4) mono-n-butyl, (5) mono-n-hexyl and (6) monocyclohexyl maleates. The emulsions may be used for coating and impregnating, and in adhesives.