GB679850A - Improved production of anion exchange resins - Google Patents

Abstract

Water-insoluble anion exchange resins are prepared by reacting at a temperature of 25-100 DEG C. a solid nuclearly halomethylated vinyl aromatic copolymer containing in chemically combined form 0.5 to 20 parts of a polyvinyl aromatic hydrocarbon of the benzene or naphthalene series and 99.5 to 80 parts of a monovinyl aromatic hydrocarbon of the benzene or naphthalene series, with a tertiary mono- or di-alkyl N-substituted alkanol or alkane-diol amine in such amount that at least one molecular proportion of the tertiary amine is present for each nuclear halomethyl radical in the copolymer. Monovinyl aromatic hydrocarbons specified are styrene, nuclear methyl, dimethyl, trimethyl, ethyl, and sec.-butyl styrenes, vinyl naphthalene and nuclear methyl vinyl naphthalene. Polyvinyl aromatic hydrocarbons specified are divinylbenzene, nuclear divinyl toluene, xylene and ethylbenzene, and divinyl naphthalene. Tertiary amines specified are dimethylaminoethanol, dimethylethanolamine, dimethylisopropanolamine, diethylethanolamine, methyldiethanolamine, methyldiisopropanolamine, dimethylpropanolamine, dioctylethanolamine, 1-dimethylamino - 2,3 - propanediol, 1 - diethylamino - 2,3 - propanediol, diethylisopropanolamine, and dibutylethanolamine. The copolymers may be prepared by mass or dispersion methods with the aid of heat or light and polymerization catalysts such as benzoyl peroxide lauroyl peroxide, hydrogen peroxide, sodium perborate, ammonium persulphate and potassium persulphate. In aqueous dispersion a protective colloid such as sodium cellulose glycollate, hydroxyethyl cellulose, or methyl cellulose, may be used to provide a granular copolymer. The copolymers are halomethylated either by treatment with a halomethylating agent such as chloromethyl or bromomethyl ethers in the presence of a catalyst such as zinc chloride, zinc oxide, stannic chloride, aluminium chloride, tin, zinc or iron, and an organic liquid such as tetrachloroethylene, chlorobenzene, or an excess of halomethylating agent, or alternatively, when the copolymer contains methyl groups attached to the aromatic nuclei, by halogenation in the presence of an organic liquid such as benzene, chlorobenzene, o-dichlorobenzene, acetic acid, tetrachloroethylene, or carbon tetrachloride, and a catalyst such as phosphorus, phosphorus trichloride, or light. The amination of the halomethylated copolymers is preferably carried out by dispersing the halomethylated copolymer in a mixture of the tertiary amine and a liquid such as water, acetone, or ethyl alcohol and heating at 70 DEG to 100 DEG in the presence of a catalyst such as cupric iodide, cuprous chloride, potassium bromide, potassium iodide and calcium iodide. Specification 654,706 is referred to. The Specification as open to inspection under Sect. 91, includes the general use of polyvinyl aromatic compounds and monovinyl aromatic compounds, such as nuclear chlorostyrene. This subject-matter does not appear in the Specification as accepted.