GB849759A - A process for the production of elastomeric plastics - Google Patents

Abstract

In a process for the production of elastomeric plastics, a reaction product of a diisocyanate, a linear or predominantly linear condensation or polymerisation product containing hydroxyl groups and having a molecular weight exceeding 1000, and, if desired, a compound having at least two hydrogen atoms reactive with isocyanates and a molecular weight lower than 500, the reaction product containing reactive hydrogen atoms and at least one of the components containing thioether bonds in the molecule, is reacted with a polyisocyanate in the presence of an acid filler. Suitable condensation or polymerisation products are condensation products containing terminal hydroxyl groups of b hydroxy-alkyl sulphides, copolymers of cyclic alkylene sulphides with alkylene oxides or polyesters derived from thiodiglycol, dihydroxy dipropyl sulphide or other sulphur containing glycols, thiodipropionic acid, thiodibutyric acid, methylene-bis-thioglycolic acid or other sulphur-containing polycarboxylic acids. Specified diisocyanates containing thioether bonds are those of the formulae OCN(CH2)3S(CH2)3NCO, OCN.C6H.4S.C6H4NCO and OCN.C6H3(CH3). .OCO (CH2)2O. CO. NH. C6H3(CH3) NCO. Specified compounds of molecular weight below 500 are those of the formulae HO(CH2)2S(CH2)2 OH, H2N(CH2)3S(CH2)3NH2, H2NC6H4SC6H4 NH2 and <FORM:0849759/IV(a)/1> Further suitable starting materials (when another component has the thioether groups) are polyesters, polyesteramides, polyethers or polyacetals; toluylene, toluidine, anisidine, 4,41-diphenylmethane, 3,31,5,51-tetramethyl 4,41-diphenylmethane, hexamethylene, p-phenylene and 1,5naphthalene diisocyanates and 1-methyl-3,5diethyl-2,4-diisocyanatobenzene ; water, glycols, aminoalcohols, diamines and polyethers of low molecular weight. Suitable acid fillers are acid varieties of carbon black, acid silicas, acid silicates, polyacrylic acids and insoluble copolymers containing COOH, SO3H or other acid groups, e.g. copolymers of methacrylic acid and styrene or sulphonated styrene. The acid fillers are preferably worked into the intermediate reaction products, together with the additional polyisocyanate, on friction rollers. Plasticisers such as phthalic, adipic, thiobutyric acid esters, tricresyl phosphate or butadiene-acrylonitrile polymers of low molecular weight can also be added.