| 摘要 |
The invention relates to a method for preparation of hydrophilic macroporous ion exchangers of the amphoteric character which are suitable above all for isolation and separation of biological materials. The preparation consists in copolymerization of anionogenous monomers, as sulfoalkyl acrylates and methacrylates, sulfoalkylacrylamides, sulfoalkylmethacrylamides, acrylic and methacrylic acid, with cationogenous monomers, as aminoalkyl acrylates and methacrylates, aminoalkylacrylamides, aminoalkylmethacrylamides and their quaternary ammonium derivatives, and with crosslinking monomers, as alkylene or oligo and polyglycol diacrylates and dimethacrylates, bisacrylamides, bismethacrylamides and divlnylbenzene, in the water dispersion system containing inert organic compounds, as alcohols, acids, amines or nitriles. Amphoteric ion exchangers are also prepared by sorption and neutralization of the macroporous hydrophilic cation exchangers with basic monomers, as vinylpyridines, aminoalkyl acrylates and methacrylates, aminoalkylacrylamides, aminoalkylmethacrylamides and their quaternary ammonium derivatives, and their subsequent copolymerization with the pendant double bonds of the cation exchangers. An analogous procedure was performed with macroporous hydrophilic anion exchangers and the acidic monomers, as sulfoalkyl acrylates and methacrylates, sulfoalkylacrylamides, sulfoalkylmethacrylamides, acrylic and methacrylic acid. Another methods for preparation of amphoteric ion exchangers consists in modification of hydroxyl groups of crosslinked acrylate, methacrylate, acrylamide and methacrylamide copolymers by parallel reactions with anionogenous and cationogenous compounds, as halogenoalkylamines, their ammonium compounds and halogenoalkane acids or in the reaction of these copolymers first with a compound containing several reactive groups in its molecule, as phosgene, epichlorohydrine, di- and polyepoxide, di- and polyisocyanate, and then with compounds rendering anions and cations or dipolar ions by dissociation, as diamines, aminoacids, hydroxyacids, and dicarboxylic acids. For this purpose, the activation of hydroxyl groups with cyanogen bromide can be used in the first step. Hydrophilic amphoteric ion exchangers may be also prepared by quaternization of amino groups in crosslinked copolymers by means of halogenoalkane acids. |
