Stable aqueous emulsions of ethylene copolymers

摘要

Stable aqueous emulsions of ethylene copolymers are made by polymerizing ethylene at pressures of over 100 atmospheres, in aqueous medium, in the absence of conventional emulsifiers, with the aid of water soluble free-radical catalysts, and in the presence a a comonomer of 0.1 to 10% by weight of at least one strongly basic amine containing a polymerizable carbon to carbon double bond, or a salt or quaternary product of the amine. Additional ethylenically unsaturated monomers may also be present in the aqueous medium. The free-radical catalyst is generally a Redox system. The amine may be allylmethyl amine, allyl dimethylamine, 4-vinyl-benzyl dimethyl amine, 4-allyl-benzyl dimethylamine, methyl-benzyl allylamine, N-vinyl-piperidine, N-vinyl-morpholine, N-allylpiperidine, N-allyl-N1-methylpiperazine, or compounds of the general formula: where R is a hydrogen atom or an alkyl radical containing from 1 to 3 carbon atoms, R1 and R11 may be the same or different, aliphatic, alicyclic, or heterocyclic radical and which with the nitrogen to which they are attached may form a heterocyclic ring, X is -R-, -O-, or -S-, and Y is a divalent alkyl or cycloalkyl radical which contains not more than 8 carbon atoms, or a reaction product of methacrylic acid ethyl ester betaisocyanate and dimethylamino-propylamine, or an allyl ester of glutamic acid or methacrylic ornithine. The free radical catalyst may be potassium, sodium, or ammonium-peroxy disulphates, perborates, or hydrogen peroxide in admixture with sodium pyrosulphite, sodium bisulphite, sodium formaldehyde-sulphoxylate, or triethanolamine. The polymerization is generally effected in a pH in the range of 5 to 9. Exemplified copolymers are ethylene and allylamine, ethylene and the sulphuric acid salt of dimethylamino-propyl-methacrylamide, ethylene and methacrylamidopropyl-dimethyl-carboxymethyl-ammonium betaine, ethylene and methacryl-oxethyl-beta-trimethyl ammonium chloride, ethylene and a compound of the formula: and a terpolymer of ethylene vinyl acetate, and methacrylamido propyl dimethyl-ammonium betaine. The emulsions may be used for coating substrates such as paper, leather, or textiles. The copolymers may be crosslinked by heat.ALSO:Cotton fabric is treated by the Foulard process with an aqueous emulsion of a copolymer of ethylene and 0.1 to 10% by weight of at least one strongly basic amine containing a polymerizable carbon to carbon double bond, or a salt or quaternary product of the amine (see Division C3), and the fabric dried at 95 DEG C. The feel of the fabric and its wear resistance is stated to be increased. The copolymers are cross-linked by heat-treatment, and they may also contain other ethylenically unsaturated monomers.