Patent GB-780905-A (GB)
Title: Plasticising and tackifying agents and rubber compositions containing the same
IPC: C08K5/098
Filed: 1955-09-01
Abstract: A plasticiser for synthetic rubber comprises 15 to 50 per cent by weight of a calcium salt of naphthenic acids derived from petroleum, at least 10 per cent by weight of a naphthenic acid, and any remainder being a neutral oil.  The calcium salt may be prepared by treating an alkali extract of crude petroleum oils or their distillates with slaked lime, and the neutral oil may be that contained in the product when the calcium salt is so prepared.  The naphthenic acid may be a mixture of naphthenic acids prepared by acidifying an alkali extract of crude petroleum oils or their distillates, which mixture contains a neutral oil. Alternatively the neutral oil may comprise residual asphalts, either per se or as liquid emulsions or solutions with an oil distillate, or extracts obtained by treating crude oil with sulphur dioxide, furfural, phenol, propane, or cresol.  The plasticizer may be used in synthetic rubber compositions together with other plasticisers such as dibutyl phthalate, dioctyl phthalate, tricresyl phosphate, triacetin, tetralin, resins known under the Registered Trade Mark "Cumar," wool glass, stearic acid, lauric acid, or pine tar.  The synthetic rubbers that may be treated include butadiene polymers; butadiene copolymers with styrene, methyl methacrylate, 3,4-di-chloro-a -methyl styrene, methyl isopropenyl ketone, and acrylonitrile; chloroprene polymers and copolymers; and polyisobutylene.  2 to 20 parts by weight of plasticiser are preferably added to 100 parts of synthetic rubber on a roll mill, or in a Banbury mixer, or to a latex or other dispersion from which the synthetic rubber is subsequently precipitated.ALSO:A plasticizer for natural or synthetic rubber comprises 15 to 50 per cent by weight of a calcium salt of naphthenic acids derived from petroleum, at least 10 per cent by weight of a naphthenic acid and any remainder being a neutral oil.  The calcium salt may be prepared by treating an alkali extract of crude petroleum oils or their distillation with slaked lime and the neutral oil may be that contained in the product when the calcium salt is so prepared.  The naphthenic acid may be a mixture of naphthenic acids prepared by acidifying an alkali extract of crude petroleum oils or their distillates, which mixture contains a neutral oil.  Alternatively the neutral oil may comprise residual asphalts, either per se or as liquid emulsions or solutions with an oil distillate, or extracts obtained by treating crude oil with sulphur dioxide, furfural, phenol, propane or cresol.  The plasticizer may be used in rubber compositions together with other plasticizers such as dibutyl phthalate, dioctyl phthalate, tricresyl phosphate, triacetin, tetralin, resins known under the Registered Trade Mark "Cumar", wool glass, stearic acid, lauric acid, or pine tar.  The synthetic rubbers that may be treated with the plasticizer include butadiene polymers, butadiene copolymers with styrene, methyl methacrylate, 3, 4-dichloroalpha-methyl styrene, methyl isopropenyl ketone, and acrylonitrile; chloroprene polymers and copolymers; and polyisobutylene 2 to 20 parts by weight of plasticizer are preferably added to 100 parts of natural or synthetic rubber on a roll mill, or in a Banbury mixer, or to latex or other rubber dispersion from which the rubber is subsequently precipitated.  In one example 10 parts by weight of a plasticizer, comprissing 2,5 parts of a mixture of a calcium salt of naphthenic acids derived from petroleum and a neutral petroleum oil and 7,5 parts of a mixture of naphthenic acids and neutral petroleum oil, are compounded with 100 parts of smoked sheet and vulcanizing and other ingredients, and the mix vulcanized.