Patent GB-583175-A (GB)
Title: Chemical compounds for use in the vulcanization of rubber
IPC: C08K5/00
Filed: 1943-09-06
Abstract: Low temperature accelerators for the vulcanization of rubber, viz., N-(di-aliphatic-thio-carbamyl-thio-methylene) aromatic amines are obtained by the interaction of a secondary aliphatic amine with formaldehyde, carbon disulphide and a primary or secondary aromatic amino compound.  The expression "secondary aliphatic amines" includes straight and branched chain, saturated and unsaturated aliphatic amines, secondary amines in which two carbon chains form with the N-atom a heterocyclic ring, cycloaliphatic or alicyclic amines, and ring substituted aliphatic amines such as aralkylamines, furfurylamines and tetrahydrofurfurylamines (prepared by the hydrogenation of hydrofuramide).  Further examples are dimethylamine, diethylamine, dibutylamine, dibenzylamine, piperidine, di-isopropylamine, dicyclohexylamine, N-methyl-cyclohexylamine, morpholine, di-a -furfurylamine, di-allylamine, and b -cyano-ethyl-cyclohexylamine (prepared by mixing cyclohexylamine with acrylic nitrile.  Specified aromatic amino compounds are: aniline, diphenylamine, o-, m-, p-toluidine, a -and b -naphthylamine, o-, m- and p-phenylenediamine, the anisidines, the phenetidines, N-phenyl -a - naphthylamine, N - phenyl - b  - naphthylamine, N,N1-diphenyl-p-phenylene diamine, o-amino diphenyl, benzidine, amino azo-benzene, the aminophenols, N-methylaniline, N-ethyl toluidines, N-cyclohexyl aniline, N-furfuryl-b -naphthylamine, benzamide, p-toluene sulphonamide, ethyl-b -anilino crotonate, ethyl-b -p-hydroxy anilino crotonate (prepared by heating p-amino phenol with ethyl aceto-acetate with the elimination of water), acetanilide, benzenesulphonamide.  The primary aromatic amino compounds may react either with one or two molecular proportions of the other ingredients.  In example 1, one mol. of aniline reacts with one mol. each of formaldehyde, carbon disulphide and dimethylamine in aqueous solution with cooling to form a compound believed to have the formula <FORM:0583175/IV/1> This compound may react with an additional mole. each of formaldehyde, carbon disulphide and dimethylamine to form a compound having the formula <FORM:0583175/IV/2> which may be obtained also by heating one mol. of aniline with two mols. each of formaldehyde, carbon disulphide and dimethylamine. If polyamines are used, each of the amino groups may enter into the reaction, this being true either of the secondary aliphatic amine or the primary or secondary aromatic amino compound.  In example 2, diphenylamine reacts with formaldehyde, carbon disulphide and dimethylamine as in 1 to form a compound believed to have the formula  <FORM:0583175/IV/3> Specification 412,914 is referred to.  The Specification as open to inspection under Sect. 91 relates also to the use of the following aliphatic amines: aralkylamines in general, furfurylamine, tetrahydrofurfurylamine, N-cyclohexyl decahydronaphthylamine and N,N1-dicyclohexyl cyclohexylene diamine.  This subject-matter does not appear in the Specification as accepted.ALSO:Low temperature accelerators for the vulcanization of rubber consisting of N-(dialiphatic - thio-carbamyl - thio - methylene) aromatic amines are obtained by the interaction of a secondary aliphatic amine with formaldehyde, carbon disulphide and a primary or secondary aromatic amino compound.