GB779995A - Anion-exchange resins containing weakly and strongly basic functional groups - Google Patents

Abstract

Anion exchange resins comprise a cross-linked polymer matrix containing aromatic nuclei, whose ring carbon atoms constitute a major proportion of the total number of carbon atoms in the matrix, to which are attached groups of the form <FORM:0779995/IV(a)/1> in which Y represents an anion, A the radical <FORM:0779995/IV(a)/2> or an alkylene radical of 2 to 6 carbon atoms, and R and R1 hydrogen atoms or methyl or ethyl groups. They may be prepared by reacting amines of the form <FORM:0779995/IV(a)/3> e.g. N,N1 - tetramethylethylenediamine and N,N-dimethylethylenediamine, with a chloromethylated copolymer of 98 to 99.5 per cent of a monovinyl aromatic hydrocarbon, e.g. styrene, vinyl toluene, vinyl naphthalene, vinyl anthracene or ethyl styrene, and 0.5 to 2 per cent of a polyvinylidene compound, e.g. divinyl benzene, divinyl toluenes, divinyl xylenes, divinyl ethyl benzenes, divinyl naphthalenes, divinyl ether, divinyl "Cellosolve" (Registered Trade Mark), ethylene glycol diacrylate, ethylene glycol dimethacrylate or dially maleate. The copolymers may be prepared by aqueous emulsion or suspension, e.g. in the presence of magnesium silicate, polymerization in the presence of a catalyst, e.g. benzoyl peroxide, and chloromethylated by reacting with paraformaldehyde and hydrochloric acid or chloromethyl methyl ether in the presence of aluminium chloride and preferably petroleum ether. The amination is preferably conducted by reacting the amine with the chloromethylated copolymer in suspension in water, toluene or ethylene dichloride. Specifications 654,706 and 779,994 are referred to.