Patent GB-583645-A (GB)
Title: Improvements in softeners for rubbers
IPC: C08K5/372
Filed: 1944-11-13
Abstract: Synthetic rubbers are plasticized by incorporating therein a di(acyl amino aryl) sulphide in the general formula <FORM:0583645/IV/1> where R is an acyl radical which may be formyl, acetyl, propionyl, butyryl, valeryl, caproyl, capryl, pelargonyl, myristyl, palmitoyl, stearoyl, margaryl, crotonyl, benzoyl, naphthoyl, p-phenyl benzoyl, mono-chloracetyl, dichlorbenzene sulphonyl, p-tolyl sulphonyl, thioacetyl or thiopropionyl.  The aromatic nucleus may be of the benzene, naphthalene or biphenyl series such as orthophenyl, metaphenyl, paraphenylene, 1, 2, naphthylamine, 1, 3, naphthylamine, 1.4.naphthylamine and 2.3.naphthylamine, and may be further substituted by groups such as alkyl, aryl, hydroxyl, halogen, aryloxy, alkoxy or tertiary amino.  The preferred di(acyl amino aryl) sulphide is 2.21-dithio-bis-acetanilide, though 3.31-dithio-bisbutyranilide, 4.41-dithio-bis-stearanilide, 2.21-dithio - bis - (4 - methyl - acetanilide), 2.21-dithio - bis - (4 - phenoxy - acetanilide), 2.21-dithio - bis - (4 - chloro - acetanilide, 2.41-dithio-bis - acetanilide, 2.21 - dithio - bis - (4 - dimethylamino acetanilide), 2.21 - dithio - bis - (1 - acetyl - naphthylamine, 2.21 - dithio - bis - formanilide, 2.21 - dithio - bis - propionanilide, 2.21 - dithio - bis - butyranilide, 2.21 - dithio - bis - benzene - sulphonanilide, 2.21 - dithio - bis-(4 - phenyl - acetanilide) or 2.21 - dithio - bis - benzanilide may be used.  The synthetic rubber may be a polymer of butadiene 1.3; methyl-2-butadiene-1.3; chloro-2-butadiene-1.3; piperylene or 2,3-dimethylbutadiene-1.3 or a copolymer of butadiene 1.3 with aryl olefins such as styrene and vinyl naphthalene; the methylene carboxylic acids and their esters, nitriles and amides such as acrylic acid, methyl acrylate, methyl methacrylate, acrylonitrile, methacrylonitrile or methacrylamide; isobutylene; methyl vinyl ether; methyl vinyl ketone and vinylidene chloride.  Preferably 0.5 to 5.0 per cent of the di(acyl-amino-aryl) sulphide is incorporated at a temperature of about 250 DEG  F. during milling. Other softening agents, vulcanising agents such as sulphur, zinc oxide and other fillers, accelerators antioxidants and pigments may also be added.ALSO:Rubber and synthetic rubbers are plasticized by incorporating therein a di (acyl amino aryl) sulphide of the general formula <FORM:0583645/V/1> where R is an acyl radical which may be formyl, acetyl, propionyl butyryl, valeryl, caproyl, capryl, pelargonyl, myristyl, palmitoyl stearoyl, margaryl, crotonyl, benzoyl, naphthoyl, p-phenyl benzoyl, mono-chloracetyl, dichloracetyl, benzene, sulphonyl, p-tolyl sulphonyl, thioacetyl or thiopropionyl.  The aromatic nucleus may be of the benzene, napththalene or biphenyl series such as orthophenylene, metaphenylene, paraphenylene, 1 :2 naphthylamine, 1 :3 naphthylamine, 1 : 4 naphthylamine and 2 :3 naphthylamine, and may be further substituted by groups such as alkyl, aryl, hydroxyl halogen, aryloxy alkoxy or tertiary amino. The preferred di (acyl amino aryl) sulphide is 2, 21 dithio bis acetanilide, though 3, 31-dithio bis butyranilide, 4, 41 dithio bis stearanilide, 2, 21 dithio bis (4 methyl acetanilide), 2, 21 dithio bis (4 phenoxy acetanilide), 2, 21 dithio bis (4 chloro acetanilide), 2, 41 dithio bis acetanilide, 2, 21-dithio bis (4 dimethylamino acetanilide), 2, 21 dithio bis (1-acetyl naphthylamine), 2, 21-dithio bis formanilide, 2, 21- dithio bis propionanilide, 2, 21 dithio bis butyranilide, 2, 21 dithio bis benzene-sulphonanilide, 2, 21 dithio bis (4 phenyl acetanilide) or 2, 21 dithio bis benzanilide may be used.  The natural rubber may be hevea braziliensis or guayule, and the synthetic rubber a polymer of butadiene 1, 3; methyl 2 butadiene 1, 3; chloro 2 butadiene 1,3; piperylene or 2,3- dimethylbutadiene 1,3 or a copolymer of butadiene 1,3 with aryl olefins such as styrene and vinyl naphthalene; the a methylene carboxylic acids and their esters nitriles and amides such as acrylic acid, methyl acrylate, methyl methacrylate, acrylonitrile, methacrylonitrile or methacrylamide; isobutylene; methyl vinyl ether; methyl vinyl ketone and vinylidene chloride. Preferably 0.5 to 5.0 per cent. of the di (acyl amino aryl) sulphide is incorporated at a temperature of about 250 DEG F. during milling.  Other softening agents, vulcanizing agents such as sulphur, zinc oxide and other fillers, accelerators, antioxidants and pigments may also be added.