GB420386A - Improvements in or relating to the production of compositions comprising organic polysulphide plastics and synthetic resins - Google Patents

Abstract

Plastic compositions of organic polysulphide plastics, of the kind obtained by the reaction of reactive halogenized hydrocarbons with a polysulphide or thiosulphate of an alkali or alkaline earth metal, and synthetic resins of the phenol-aldehyde, polyhydric alcohol-polycarboxylic acid and aldehyde-arylamine types are manufactured by dissolving the organic polysulphide plastic in one of the parent substances for the resin and completing the formation of the latter after the addition of the remaining parent substance or substances. The process may be carried out by dissolving the plastic in an aromatic hydroxy compound or compounds, e.g. phenol, and reacting the solution with an aldehyde, e.g. formaldehyde or acetaldehyde, or a mixture of aldehydes, the aldehyde being, if desired, generated in situ; or by dissolving the plastic in a polybasic acid or anhydride or a mixture thereof, e.g. phthalic anhydride or a mixture thereof with an aliphatic dicarboxylic acid, and treating the solution with one or more polyhydric alcohols, e.g. glycerol or a mixture of glycerol and glycol; or by dissolving the plastic in an aromatic amine, e.g. aniline, or a mixture of amines, and reacting the solution with one or more aldehydes, e.g. acetaldehyde. The polysulphide plastics may be prepared by reacting di- or polyhalogenated saturated or unsaturated hydrocarbons with a polysulphide or thiosulphate of an alkali or alkaline earth metal, and in the latter case removing the metallic radicle by hydrolysis, oxidation or reduction. The products are suitable for addition to rubber for improving its impermeability and oil- and solvent-resistance. In examples: (1) diethylene tetrasulphide (obtained by refluxing a mixture of an alcoholic solution of ethylene dichloride and aqueous sodium thiosulphate and heating the product with hydrogen peroxide) is dissolved in molten phenol and the solution is treated with formalin in the presence of hydrochloric acid; the product may be added to a rubber mix containing sulphur, zinc oxide, mercaptobenzthiazole, stearic acid and carbon black, which is then vulcanized; (2) diethylene tetrasulphide is dissolved in molten phthalic anhydride and the mixture as heated with glycerol and succinic acid; (3) diethylene tetrasulphide is dissolved in molten phenol and the solution is heated with paracetaldehyde in the presence of sulphuric acid; (4) diethylene tetrasulphide is dissolved in hot aniline and the mixture is refluxed with aqueous formaldehyde.ALSO:The impermeability and oil- and solventresistance of rubber are improved by the addition of plastic compositions of organic polysulphide plastics, of the kind obtained by the reaction of reactive halogenized hydrocarbons with a polysulphide or thiosulphate of an alkali or alkaline earth metal, and synthetic resins of the phenol-aldehyde, polyhydric alcohol-polycarboxylic acid and aldehyde-arylamine types, obtained by dissolving the organic polysulphide plastic in one of the parent substances for the resin and completing the formation of the latter after the addition of the remaining parent substance or substances. In an example, a plastic composition produced by dissolving diethylene tetrasulphide in molten phenol and treating the solution with formalin is added to a rubber mix containing sulphur, zinc oxide, mercaptobenzthiazole, stearic acid, and carbon black, which is then vulcanized.