GB489157A - Improvements in and relating to the preservation of rubber - Google Patents

Abstract

The deterioration of rubber is retarded by the addition of an aryloxy substitued diarylamine of the general formula R-O-R1-NH-R2, in which R, R1 and R2 represent aromatic radicals. In preferred forms of the invention R and R2 are phenyl, tolyl, xylyl, diphenyl, naphthyl and anthracyl radicals, and R1 is a phenylene, toluylene xylylene, naphthylene and diphenylene radical. Compounds mentioned as being particularly suitable for use according to the present invention are 4-phenoxy-phenyl-b -naphthylamine, 4-phenoxy-diphenylamine, 4-p-cresoxy-phenyl-b -naphthylamine, 2 - phenoxy - phenyl - b - naphthylamine, 4 - b - naphthoxy - phenyl - b -naphthylamine, 4 - phenoxy - 41 -methoxydiphenylamine, and 4 : 41-diphenoxy-diphenylamine. In examples: (1) 4-amino-diphenyl ether and b -naphthol are reacted in the presence of iodine for five hours at 225-260 DEG C. to yield 4-phenoxy-phenyl-b -naphthylamine; (2) 4 - amino - diphenyl - ether and aniline hydrochloride are reacted as in example (1) to give 4-phenoxy-diphenyl-amine; (3) 4-amino-41-methyl diphenyl ether is reacted as in example (1) with beta-naphthol to give 4-para-cresoxy-phenyl-beta-naphthylamine; (4) 2-amino-diphenyl ether is reacted as in example (1) with beta naphthol to give 2-phenoxyphenyl-beta-naphthylamine; (5) 4-amino-phenyl alpha-naphthyl ether is reacted as in example (1) with beta naphthol to give 4-alpha-naphthoxy-phenyl-beta naphthylamine. The anti-oxidants of the present invention may be used either alone or in combination with other anti-oxidants. The term "rubber" includes caoutchouc, both natural and synthetic, reclaimed rubber, balata, guttapercha and rubber isomers. Tables are given to show the efficiency of the anti-oxidants of the present invention when used in a standard rubber mix.ALSO:The deterioration of rubber is retarded by the addition of an aryloxy substituted diarylamine of the general formula R-O-R1-NH-R2 in which R, R1 and R2 represent aromatic radicals. In preferred forms of the invention R and R2 are phenyl, tolyl, xylyl, diphenyl, naphthyl and anthracyl radicals, and R1 is a phenylene, toluylene, xylylene, naphthylene and diphenylene radical. Compounds mentioned as being particularly suitable for use according to the present invention are 4-phenoxy-phenyl-b -naphthylamine 4-phenoxy-diphenylamine, 4-p-cresoxyphenyl-b -naphthylamine, 2-phenoxyphenyl-b -naphthylamine, 4-a -naphthoxyphenyl - b - naphthylamine, 4 - phenoxy - 41 - methoxy - diphenylamine and 4 - 41 - diphenoxy - diphenylamine. Examples are given to show methods of preparation of the invention. The anti-oxidants may be used either alone or in combination with other anti-oxidants. The term rubber includes caoutchouc, both natural and synthetic, reclaimed rubber, balata, guttapercha, and rubber isomers. Tables are given to show the efficiency of the anti-oxidants of the present invention when used in a standard rubber mix.