GB869112A - Alkylene oxide-copolymers - Google Patents

Abstract

Thermoshardening solid copolymers suitable for use as moulding materials or rubber substitutes are obtained by co-polymerizing at least 50 mol per cent of ethylene oxide with one or more other epoxide monomers, at least one of which has olefinic unsaturation. Suitable unsaturated oxides are butadiene monoxide, glycidyl crotonate, beta-methyl glycidyl crotonate, allyl glycidyl ether, allyl beta-methyl glycidyl ether, divinyl benzene monoxide, 2, p 5-dimethyl-5, 6, epoxy-1-hexene, allyl glycidyl sulphone and chloroprene oxide. The mixture of monomeric starting materials may also include propylene or butylene oxides or styrene oxide and the copolymers may be terpolymers. The polymerization is effected in presence of catalysts which are carbonates of divalent metals having atomic numbers greater than 11 and less than 57 e.g. Mg, Ca, Sr, Ba, Zn, Cd, Fe, Co, Ni, Cr, and Mn the preferred catalysts being those of Group IIA and manganous carbonate. Improved catalyst activity is obtained by using catalysts containing only absorbed water in an amount of 0,01% to 0,1%, e.g. by drying the carbonates at about 55 DEG C. for 12 hours. Polymerization can also be effected in presence of alkaline earth derivatives of organic hydroxy compounds, e.g. strontium methylate, or the calcium derivative of a glycol. Certain of these catalysts benefit from exposure to CO2 and water before use. The polymerization may be effected in bulk or in presence of diluents comprising benzene, alkyl benzenes, chlorbenzene, hydrocarbon ethers and liquid saturated straight or branch chain aliphatic hydrocarbon as described in Specification 869,114. Ethylene oxide purified by distillation through a drying agent is preferably employed and the polymerization is stabilized by addition of a hydrocarbon gas, e.g. butane. In Examples (1) to (8) butadiene monoxide and ethylene oxide in various proportions were heated in presence of SrCO3 in a sealed tube at 92 DEG C.; (9) a mixture of butadiene monoxide, 1, 2-epoxybutane and ethylene oxide was similarly treated. The product was cured by heating to 140 DEG C. admixed with phenyl beta naphthylamine, sulphur, stearic acid and mercaptobenzothiazole, zinc oxide and butyraldehyde-aniline condensate as accelerator; (10) and (11) mixtures of chloroprene oxide and ethylene oxide were similarly polymerized at 90 DEG C. Specifications 869,113, 869,115 and 869,116 also are referred to.