GB575736A - Improvements in the preservation of rubber compositions - Google Patents

Abstract

An antioxidant or age-resistor for incorporation in natural or synthetic rubber compositions comprises an N-aryl-N1-alkyl-N1-arylsulphonyl-arylenediamine of the general formula <FORM:0575736/IV/1> wherein A represents an open-chain aliphatic, cycloalkyl, or aralkyl hydrocarbon group, optionally substituted; "aryl" represents a benzene, naphthalene or biphenyl residue and "arylene" represents an aromatic residue containing one or more rings. As further nuclear substituents, the N-aryl group may carry alkyl, alkenyl, alkoxy, aryloxy, dialkylamino or anilino groups, or halogen atoms; the arylene nucleus may carry alkyl or alkoxy groups or halogenatoms, the N1-aryl nucleus of the arylsulphonyl group may carry, for example, alkyl groups, and the N1-alkyl radical may carry chlorine atoms or alkoxy or amino groups. The substances are prepared, in general, by treating an arylsulphonylaminodiarylmaine in alkaline solution with an aliphatic halide or sulphate. As antioxidants are specified (a) the following p-phenylenediamine derivatives, viz. the N-phenyl-N1-methyl-N1-benzenesulphonyl-, N - phenyl - N1 - ethyl - N1 - benzenesulphonyl-, N - phenyl - N1 - butyl - N1 - benzenesulphonyl-, N - phenyl - N1 - lauryl - N1 - benzenesulphonyl-, N - phenyl - N1 - allyl - N1 - benzenesulphonyl-, N - phenyl - N1 - b - methallyl - N1 - benzenesulphonyl-, N-phenyl-N1-cyclohexyl-N1-benzenesulphonyl-, N-phenyl-N1-benzyl-N1-benzenesulphonyl-, N-p-tolyl-N1-methyl-N1-benzenesulphonyl-, N-p-methoxyphenyl-N1-methyl-N1-benzenesulphonyl-, N-phenyl-N1-methyl-N1-p-toluenesulphonyl-, N-phenyl-N1-methyl-N1-p-toluenesulphonyl-, N-phenyl-N1-methyl-N1-p-biphenylsulphonyl-, N - phenyl - N1 - b - hydroxyethyl-N1-benzenesulphonyl-, N-phenyl-N1-b -methoxyethyl-N1-benzenesulphonyl- and N-phenyl-N1-b -chloroethyl-N1-benzenesulphonyl -derivatives; (b) N-phenyl-N1-methyl-N1-benzenesulphonyl-o -phenylenediamine and the corresponding m-phenylenediamine derivative; (c) N-phenyl-N1-methyl-N1-benzene - sulphonyl-1 : 4-naphthylene diamine and the corresponding benzidine derivative. N-p-tolyl-N1-b -methallyl-N1-p-toluenesulphonyl-p -phenylenediamine is obtained by heating under reflux b -methallylchloride with N-p-tolyl - N1 - p - toluenesulphonyl - p - phenylene - diamine (Cf. Specification 406,479) in alcohol, containing aqueous potassium hydroxide and sodium hydrosulphite. N-p-tolyl-N1-methyl-N1-p-toluenesulphonyl-p -phenylenediamine is obtained by interaction of dimethyl sulphate and N-p-tolyl-N1-p-toluenesulphonyl - p - phenylenediamine in aqueous potassium hydroxide. N-p-tolyl-N1-ethyl-N1-p-toluenesulphonyl-p -phenylenediamine is obtained by interaction of diethyl sulphate and N-p-tolyl-N1-p-toluenesulphonyl - p - phenylenediamine in aqueous alcoholic potassium hydroxide containing sodium hydrosulphite. N-phenyl-N1-methyl-N1-p-toluenesulphonyl-p -phenylenediamine is obtained by interaction of dimethyl sulphate and N-phenyl-N1-p-toluenesulphonyl - p - phenylenediamine (Cf. Specification 406,479) in aqueous potassium hydroxide containing sodium hydrosulphite.ALSO:Compositions of natural and synthetic rubber, including polychloroprene, olefine polysulphides, butadiene polymers, "Buna" (Registered Trade Mark) N and Buna S and also reclaims and latices of such compositions, are preserved by incorporating therein as an antioxidant or age-resister an N - aryl - N1 - alkyl - N1 - arylsul - phonyl-arylene diamine of the general formula <FORM:0575736/V/1> wherein A represents an open-chain aliphatic, cycloalkyl, or aralkyl hydrocarbon group, optionally substituted, "aryl" represents a benzene, naphthalene or biphenyl residue and "arylene" represents an aromatic residue containing one or more rings. As further nuclear substituents, the N-aryl group may carry alkyl, alkenyl, alkoxy, aryloxy, dialkylamino or anilino groups, or halogen atoms, the arylene nucleus may carry alkyl or alkoxy groups, or halogen atoms and the N1-aryl nucleus of the arylsulphonyl group may carry, for example, alkyl groups and the N1-alkyl radical may carry chronine atoms or alkoxy or amino groups. The substances are prepared, in general, by treating an arylsulphonylaminodiarylamine in alkaline solution with an aliphatic halide or sulphate (see Group IV). As antioxidants are specified (a) the following p-phenylenediamine derivatives, viz., the N-phenyl-N1-methyl-N1-benzenesulphonyl-, N - phenyl - N1 - ethyl - N1 - benzenesulphonyl-, N - phenyl - N1 - butyl - N1 - benzenesulphonyl-, N - phenyl - N1 - lauryl - N1 - benzenesulphonyl-, N - phenyl - N1 - allyl - N1 - benzenesulphonyl-, N - phenyl - N1- b - methallyl - N1 - benzenesulphonyl-, N - phenyl - N1 - cyclo - hexyl - N1 - benzenesulphonyl-, N - phenyl - N1 - benzyl - N1 - benzenesulphonyl, N - p - tolyl - N1 - methyl - N1 - benzenesulphonyl-, N - p - methoxy - phenyl - N1 - methyl - N1 - benzenesulphonyl-, N - phenyl - N1 - methyl - N1 - p - toluenesulphonyl-, N - phenyl - N1 - methyl - N1-p-biphenylsulphonyl-, N - phenyl - N1 - b - hydroxyethyl - N1 - benzenesulphonyl-, N - phenyl - N1 - b - methoxyethyl - N1 - benzenesulphonyl- and N-phenyl-N1-b -chloroethyl - N1 - benzenesulphonyl - derivatives, and the compounds; (b) N-phenyl-N1-methyl-N1-benzenesulphonyl-o -phenylenediamine and the corresponding m-phenylenediamine derivative; (c) N-phenyl-N1-methyl-N1-benzenesulphonyl-1 : 4-naphthylene diamine and the corresponding benzidine derivative. The antioxidant may advantageously be in proportion from about 0.1 per cent to 5 per cent and it may be added in solution or incorporated by milling or mastication or prepared in forms suitable for incorporation by diffusion. In examples: (1) (a) 1 per cent of N-p-tolyl-N1-methyl-N1-p-toluenesulphonyl-p -phenylenediamine, (b) 1 per cent of N-p-tolyl-N1-b -methallyl-N1-p-toluenesulphonyl-p -phenylenediamine is incorporated in a composition comprising pale crepe rubber, tetramethylthiuram monosulphide, zinc oxide, calcium carbonate, lithopone, the zinc salt of coconut oil acids and sulphur; (2) (a) 1 per cent of N-p-tolyl-N1-ethyl-N1-p-toluenesulphonylamino - p - phenylenediamine, (b) 1 per cent of N-phenyl-N1-methyl-N1-p-toluenesulphonyl-p -phenylenediamine is incorporated in a composition comprising smoked sheet rubber, mercaptobenzothiazole, carbon black, zinc oxide, pine tar, the zinc salt of coconut oil acids and sulphur.