GB634757A - Improved catalytic polymerisation of ethylene - Google Patents

Abstract

Polymers and interpolymers of ethylene are made by subjecting ethylene alone or together with a substance which will interpolymerize therewith to superatmospheric temperature and to a pressure above 100 atmospheres in the presence of a catalyst of formula X - N = N - Y, where X is an aliphatic radical, and Y any radical in which a carbon atom is attached directly to the azo nitrogen. The polymerization may be effected in the presence of a liquid medium, which may participate in the reaction. Specified non-reactive media are benzene, toluene, water or water and the reaction product of ethylene oxide and phenol as dispersing agent. The reactive media may be t-butanol, 1-3-dioxolane, cyclohexane, neohexane, acetals, ethers, esters, acids or carbon tetrachloride. The preferred temperatures are between 40 DEG and 100 DEG C. and the pressures between 500 and 3000 atmospheres. The interpolymerizing substances may be vinyl chloride, vinyl acetate, vinyl methyl ketone, tetrafluorethylene, diethyl fumarate, diethyl maleate, carbon monoxide, or sulphur dioxide. Hydrogen may also be present. Specified catalysts are alpha, alpha1-azodiisobutyronitrile; alpha, alpha1 - bis - cyclohexanecarbonitrile; alpha, alpha1 - bis - alpha gamma dimethylvaleronitrile; alpha phenylazoisobutyronitrile; alpha-carbamylazoisobutyronitrile; alpha-carbamylazocyclohexanecarbonitrile; dimethyl alpha, alpha1-azodiisobutyrate; and azodisopropane. The products may be used in wax polishes and for forming films. Specification 622,374 is referred to.