Patent GB-853428-A (GB)
Title: Curing air-blown oils with blocked isocyanates
IPC: C08G18/69
Filed: 1958-06-30
Abstract: Oxidised oily polymers or copolymers of conjugated diolefines containing at least 10% by weight of oxygen are cured in the presence of a reaction product of an organic polyisocyanate and an organic polyhydroxy compound, the amount of such product being such that there is present, per 5 grams of oil, 0,0038-0,0304 equivalent of free isocyanate.  The polymer may be formed from C4-C6 conjugated dienes such as butadiene, isoprene, dimethylbutadiene, piperylene or methylpentadiene alone, mixed with each other, or mixed with minor amounts of styrene, para.-methylstyrene, dimethylstyrene, diethylstyrene, acrylonitrile, methacrylonitrile, methyl acrylate or methacrylate, vinyl isobutyl ether, methyl vinyl ketone or methyl isopropenyl ketone.  Suitable polymerization catalysts are benzoyl peroxide, cumene hydroperoxide and sodium preferably in a solvent. The oil is oxidized by blowing with air in the presence of a solvent, preferably aromatic hydrocarbons and their mixtures, to introduce 10-20 weight per cent of oxygen; suitable catalysts are the naphthenates and octoates of lead, cobalt, iron and manganese in amounts of 0,001-1% and to which may be added benzoyl peroxide. Suitable polyisocyanates are tolylene-2,4-diisocyanate; 3,31-bitolyl-4,41-diisocyanate; diphenylmethane-4,41-diisocyanate and hexamethylene diisocyanate.  The polyhydroxy compound may be glycerol, trimethylolethane, trimethylol propane or pentaerythritol and is reacted with the polyisocyanate in about equimolar proportions. The polymer oils may be air dried at room temperature or baked at 150-250 DEG F. for 10-30 minutes.ALSO:Oxidised oily polymers or copolymers of conjugated diolefines containing at least 10% by weight of oxygen are cured in the presence of a reaction product of an organic polyisocyanate and an organic polyhydroxy compound, the amount of such product being such that there is present, per 5 grams of oil, 0.0038-0.0304 equivalent of free isocyanate.  The polymer may be formed from C4-C6 conjugated dienes such as butadiene, isoprene, dimethylbutadiene, piperylene or methylpentadiene alone, mixed with each other, or mixed with minor amounts of styrene, para-methylstyrene, dimethylstyrene, diethylstyrene, acrylonitrile, methacrylonitrile, methyl acrylate or methacrylate, vinyl isobutyl ether, methyl vinyl ketone or methyl isopropenyl ketone.  Suitable polymerization catalysts are benzoyl peroxide, cumene hydroperoxide and sodium preferably in a solvent. The oil is oxidised by blowing with air in the presence of a solvent, preferably aromatic hydrocarbons and their mixtures, to introduce 10-20% weight of oxygen; suitable catalysts are the naphthenates and octoates of lead, cobalt, iron and manganese in amounts of 0.001-1% and to which may be added benzoyl peroxide. Suitable polyisocyanates are tolylene-2,4-diisocyanate; 3,31-bitolyl-4,41-diisocyanate; diphenylmethane-4,41-diisocyanate and hexamethylene diisocyanate. The polyhydroxy compound may be glycerol, trimethylolethane, trimethylol propane or pentaerythritol and is reacted with the polyisocyanate in about equimolar proportions. The polymer oils may be air dried at room temperature or baked at 150-250 DEG F. for 10-30 minutes.  Films of 0.25-5.0 mils thick may be formed by brushing or spraying at 10-40 DEG C.  In the example coatings are formed on steel panels and dried at various temperatures without a drier.  The coatings may also be used for pipelines, tank linings, wood finishes, glass laminates, pressed boards and impregnants.