Modified carbon black and methods of preparing and using same

摘要

The "X value" of carbon black is raised to above 75, preferably to 80-200, by severe attrition in the presence of oxygen at a temperature of 0-200 DEG C., preferably 20-100 DEG C. where A is surface area in acres/lb., and S is porosity in gallons of oil absorbed/100 lb. The black treated may be furnace or thermal black, may have a pH of about 4.25-10, preferably above 6, a surface area of 1.57-15.35, and a porosity of 4.8-300. After treatment, the black may have a pH of 2-5.9, a surface area of 2.13-27.3 and a porosity of 4-8.04. The attrition may be carried out by milling with balls having a density of at least 7, e.g. of steel having a diameter of 0.25-2 inches, rolling between tight steel rolls set to a clearance of up to 0.01, by jet impact, or by supersonic vibration alone or together with another attrition means, in the presence of oxygen, oxygen-enriched air, air, or nitrogen, at a temperature of 0-200 DEG C., preferably 20-100 DEG C., and for a period of 1-54 hours. Operation may be batch-wise or continuous. Examples are given.ALSO:A rubber composition comprises an attrited carbon black (see Group III) and natural rubber, or a butyl or halogenated butyl rubber, or butadiene-styrene, butadiene-acrylonitrile, or neoprene rubber. The composition may comprise 10-150 parts of black per 100 parts of rubber. The butyl rubber may have a Staudinger molecular weight of 20,000-300,000 and a Wijs iodine number of 0.5-50, and may be prepared from 0.5-15% of butadiene, isoprene, or cyclopentadiene, 0.8-8% (optional) of divinylbenzene or dimethallyl, 0.5-10% (optional) of styrene, p-methyl styrene, or indene, and the balance isobutylene or 2-methyl butene-1. The halogenated butyl rubber may have a mol. percentage unsaturation of 0.5-15.0 and may contain at least 0.5%, preferably at least 1.0% of halogen. Halogenating agents specified are gaseous chlorine, liquid bromine, iodine monochloride, sulphuryl chloride, sulphuryl bromide, bromohydantoins, N-bromo-succinimide, a -chloroaceto-acetanilide, N,N1-dichloro - 5,5 - dimethylhydantoin, N - chloroacetamide, and b -bromo-methyl phthalimide. The rubber composition may also contain 5-100 parts of a plasticizer oil per 100 parts of rubber, which may be a petroleum oil of a paraffinic, naphthenic, or aromatic type, or an ester type plasticizer, e.g. dibutyl phthalate, dihexyl sebacate, or trioctyl phosphate. Before vulcanizing, the rubber composition may be subjected to a heat treatment at a temperature of 250-500 DEG F. for a period of 5 mins. 8 hours. The treatment may be static, or with agitation, e.g. in a Banbury mixer or between heated steel rolls. Treatment with and without agitation may be carried out alternately in succession. A heat treatment promoter, e.g. 0.1-1.0% of paradinitrosobenzene, paraquinone - dioxime, sulphur, tetramethylthiuramdisulphide, paranitrosophenol, or N-4-dinitroso-N-methylaniline, may be used.