Abstract: The invention comprises the manufacture of cation exchangers by the copolymerization of a sulfonic acid with two other monomers such as acrylamide and n-methylolacrylamide which react simultaneously with the polymerization to form a cross-linking unit. The non-polymerizing (NP) solvent employed is water.

Abstract: A packing material for chromatographic use which comprises an inorganic carrier having hydroxyl groups at the surface thereof having grafted thereon an .alpha.-arylalkylamine derivative which is formed by bonding an optically active .alpha.-arylalkylamine and an aminoalkylsilane through a dibasic carboxylic acid, and a method for liquid chromatographic analysis of an enantiomer mixture using this packing material as a stationary phase. The packing material of the present invention can be easily produced by the usual chemical reaction, is chemically stable, and exhibits excellent effects in the separation of an enantiomer mixture of a compound having an --NH-- group, --CONH-- group, or an --OCO-- group bonded to an asymmetric carbon atom thereof.

Abstract: This invention relates to the manufacture of anion selective membranes in a "one-step" process by co-polymerization of a crosslinking methacrylate ester and a methacrylic ester containing a quaternary ammonium group. The anion selective membranes are obtained directly with no further processing needed.

Abstract: Fluorinated ion exchange polymers which have pendant side chains which contain --OCF.sub.2 COOR groups, or which have both pendant side chains containing carboxylic groups and pendant side chains which contain sulfonyl groups, when used in the form of membranes to separate the anode and cathode compartments of an electrolysis cell, permit operation at high current efficiency. Those containing both carboxylic and sulfonyl groups can be made by oxidation of fluorinated polymers which have pendant side chains containing sulfinic groups, or both sulfinic and sulfonyl groups. The fluorinated polymers which have pendant side chains containing sulfinic groups, or both sulfinic and sulfonyl groups, are in turn made from fluorinated polymers which have pendant side chains containing sulfonyl halide groups by reduction with, for example, hydrazine. Those polymers which have only pendant side chains which contain --OCF.sub.

Abstract: An ion exchanger comprising a crosslinked copolymer and an ion exchange group, wherein an alcoholic hydroxyl group is bonded directly to the skeleton of a matrix of totally porous organic synthetic crosslinked copolymer. The ion exchanger has a predetermined hydroxyl group content, predetermined ion exchange group content, predetermined water regain value and predetermined specific surface area. The ion exchanger having a high mechanical strength and high chemical stability and not causing non-specific adsorption of bio-substances is useful as a high-speed liquid chromatography packing material and separating membrane, especially for bio-substances, such as protein, enzyme, peptide, amino acid, nucleotide or the like.

Abstract: A novel fluorinated copolymer is prepared by copolymerization of a fluorinated olefin with a novel sulfur containing fluorinated vinylether of the formula: ##STR1## wherein k is 0 or 1 and l is an integer of 3 to 5, which is prepared from starting materials, which are also novel. Said copolymer is useful for preparation of a fluorinated cation exchange membrane having carboxylic acid groups and/or sulfonic acid groups which can be used advantageously in electrolysis of an aqueous alkali metal halide solution with improved electrolysis performance.

Abstract: An amphoteric ion exchanger constituted by linking (1) first macromolecular chain A.sup.- having cation exchange groups, (2) second macromolecular chain B.sup.+ having anion exchange groups and (3) third macromolecular chain C having no ion exchange group into a straight chain to have a linking mode of the first chain and the second chain being separated from each other by the third chain.

Abstract: .beta.-substituted polyfluoropropionate salts, derivatives and copolymers and processes for the preparation thereof.

Abstract: A filler for liquid chromatography, said filler consisting essentially of a hydrophilic ion-exchanger obtained by copolymerizing a mixture of (A) 5 to 90% by weight of a polymerizable monomer containing one polymerizable double bond and at least one carboxyl group per molecule and having a hydrophobic parameter of not more than 2.3, (B) 10 to 95% by weight of a crosslinkable polymerizable monomer containing at least two polymerizable double bonds per molecule and having a hydrophobic parameter of not more than 2.3, and (C) 0 to 85% by weight of a monomer being different from the monomer (A), containing one polymerizable double bond per molecule and having a hydrophobic parameter of not more than 2.3; and a method for separating a biological material such as proteins, enzymes and amino acids by liquid chromatography using the aforesaid filler.

Abstract: Tridimensional cross-linked random copolymers, insoluble in water, containing in copolymerized form: (a) 25% to 98% by weight of N-[tris(hydroxymethyl)methyl]acrylamide or N-[tris(hydroxymethyl)methyl]methacrylamide, or a mixture of these two compounds. (b) 2% to 50% by weight of one or more monomers containing two or several polymerizable ethylenic double bonds and free from anionic or cationic functional groups, and (c) 0.1% to 50% by weight of one or more monomers containing a polymerizable ethylenic double bond and one or more mono- or di-substituted amino, pyrimidinyl, guanidyl, purinyl, quaternary ammonium, SO.sub.3 H or SO.sub.3 M groups, M being an alkali metal. These copolymers are utilizable, in the form of aqueous gels, as ion exchangers.

Abstract: A process for the preparation of insoluble, only slightly swellable, granular polymers of basic vinyl-heterocyclic compounds and of their copolymers with up to 30% by weight of copolymerizable monomers and 0.1-10% by weight of crosslinking agent by exclusion of (atmospheric) oxygen from the mixture of monomer and crosslinking agent, without addition of any initiator or catalyst, and the use of the polymers obtained as ion exchangers, adsorbents and carriers for proteins.

Abstract: Spheroidal polymer beads having a uniform size are prepared by polymerizing uniformly sized monomer droplets formed by the vibratory excitation of a laminar jet of monomeric material flowing in a continuous liquid medium containing a suitable suspending agent. For example, a laminar jet of a monomer mixture comprising a monovinylidene aromatic such as styrene, a polyvinylidene aromatic such as divinylbenzene and a polymerization initiator can be subjected to vibratory excitation and the resulting monomer droplets polymerized to yield copolymer beads having a narrow particle size range distribution. The resulting copolymer beads can be employed to prepare high yields of ion exchange resins exhibiting superior properties, particularly in continuous ion exchange operations.

Abstract: Novel imidazolylmethylstyrene compounds which are basic compounds and have excellent resistance to oxidation and high polymerizability are disclosed. The basic compound of the present invention is prepared by reacting a halogenomethyl-styrene with an imidazole compound, and can be used, for example, as a curing agent for epoxy resins. The imidazolymethylstyrene compounds are readily homopolymerized or copolymerized to provide linear homopolymers, linear copolymers or cross-linked copolymers having pendant imidazolylmethylphenyl groups. These polymers have greater resistance to oxidation than the homologues, and are useful as an ion exchange resin, extractant of metals, sizing agent and antistatic agent.

Abstract: A method of obtaining deuterated compounds from compounds having an abstractable proton comprises contacting the proton-containing compound with a porous ion exchange resin which contains at least some deuterons. The reverse process of substituting protons for deuterons in deuterated compounds is also described. Highly pure products can be obtained.

Abstract: There is provided a cholesterol reducing agent which contains as an active ingredient an anion exchange resin having a functional group of an imidazolium salt represented by the formula: ##STR1## wherein the substituents R.sub.1a through R.sub.4a and X.sup..crclbar. are as defined in the specification and claims.The cholesterol reducing agent according to the present invention has a high selectivity for the adsorption of bile acids and has no bad smell.

Abstract: A polymeric ion exchange resin of the cross-linked type in which the active groups may be constituted either wholly or in part by an imidazole group which is, in turn, attached directly to a cross-linked, polymerized vinyl backbone. The optional substituents on the imidazole ring include optionally substituted pyridyl, imidazolyl or amino groups which can be substantially known type. A method of preparation of such resins includes the provision of at least the imidazole ring on the vinyl monomer before polymerization thereof. The active groups may be added or modified after polymerization with a cross-linking agent.

Abstract: These resins are in particular non toxic styrene, acrylic or epoxy resins, with strong cholesterol-decreasing properties, which have an apparent density in water of 0.18 to 0.20 g of dry material/ml and a water absorption capacity of 69 to 73% by weight of the polymer weight.The process for producing anionic ion exchange resins with strong cholesterol-decreasing properties in which a mixture of monomers containing a critical percentage of cross-linking monomer, consists of polymerizing at a low rate so as to give the polymer a critically predetermined and uniformly distributed degree of cross-linkage, corresponding to an apparent density in water of 0.18 to 0.20 of dry material/ml with a water absorption capacity of 69 to 73% by weight of the polymer weight, wherein the polymerization catalyst used in an organic peroxide in a concentration of 0.2 to 3%, and the cross-linking agent used is a divinyl compound in a percentage of 1.5 to 12%, at a polymerization temperature of 50.degree. to 80.degree. C.

Abstract: Perfluoroketovinyl ether of the formula (as in claim 1) wherein n is an integer 1 to 4, copolymers of such ether and a fluorinated monomer, such as tetrafluoroethylene; ion-exchange resins of such copolymers; and ion-exchange membranes of such resins.

Abstract: Linear addition polymer beads having repeating units of vinylbenzyl alcohol and at least one other structure different from vinylbenzyl alcohol, wherein the vinylbenzyl alcohol units comprise at least 0.5% by weight of the linear polymer, and thermally crosslinked derivatives thereof. The beads are thermally crosslinked by heating during formation thereof or thereafter in the presence of a free radical initiator, such that alpha-hydroxy benzylic methylene or benzyloxy crosslinks are formed between aromatic rings of the vinylbenzyl alcohol units, and between the vinylbenzyl alcohol units and other active sites in the polymer. The linear addition polymers may be formed directly from vinylbenzyl alcohol monomer and at least one other monomer, or indirectly by hydrolysis of vinylbenzyl chloride during linear polymer formation therefrom. The crosslinked products are useful as adsorbents, hydrogels and as intermediates in the preparation of other adsorbents, ion exchange resins, catalysts and slow release agents.

Abstract: A process for preparing reticular crosslinked copolymer beads by suspension copolymerization in an aqueous medium a polyvinylidene monomer and a monovinyl aromatic hydrocarbon monomer in a liquid precipitant which has a low solubility in the aqueous medium, is a solvent for the monomer mixture and does not appreciably swell the copolymer, the liquid precipitant and said polyvinylidene monomer each being present in an amount exceeding the critical concentration of each needed for phase separation of the copolymer from the monomer phase, and the products produced by said process.

Abstract: The reaction of glycidyl methacrylate (GMA) with an ionogenic methacrylate ester containing amine groups of the tertiary type such as dimethylaminoethyl methacrylate (DMAEMA) in the presence of an acidic water solution produces a new and novel water soluble, ionic, cross-linking, methacrylate bifunctional monomer which is useful in the manufacture of anion exchange polymers while employing an aqueous solvent system.

Abstract: Base stable aliphatic anion exchangers are produced by reacting a water soluble methacrylate ester quaternary amine monomer with a non-water soluble glycol dimethacrylate ester cross-linking monomer.

Abstract: Water-soluble polyacetylenic alkali metal salts from monomers and polymers of carboxymethyl urethanes of di-, tetra-, and hexayne diols, or from the corresponding diacids; useful in thermal and irradiation exposure indicators and/or in detection and/or removal of nonalkali metal ions dissolved in aqueous media.

Abstract: A ternary block copolymer and a method for manufacturing it. The copolymer has a molecular structure consisting of a macro-molecule having a cation exchange group, a macro-molecule having an anion exchange group and another macro-molecule which does not have any ion exchange group. These macro-molecules are linked together into a straight chain.

Abstract: A porous cross-linked copolymer of chloromethylstyrene and divinylbenzene having a divinylbenzene unit represented by Xm of from about 9.0 percent by mole to about 17.0 percent by mole based on the total moles of monomer units; a content of active chlorine atom of from about 5.25-0.08 Xm mmole/g-dry resin to about 6.43-0.10 Xm mmole/g-dry resin; a water regain of from about 0.10 ml/g-dry resin to about 1.20 ml/g-dry resin; and a total volume of micro pores having a diameter of from about 500 angstroms to about 3000 angstroms of from 0.10 ml/g-dry resin to about 1.20 ml/g-dry resin; and a porous iminodiacetic acid type chelating resin having a Xm of from about 9.0 percent by mole to about 17.0 percent by mole based on the total moles of all monomer units; an ion exchange capacity of from about 5.35-12.0 Xm/(205.6-1.30 Xm) meq/g-dry resin to about 7.93-18.1 Xm/(247.1-2.0 Xm) meq/g-dry resin; a water regain of from about 0.60 ml/g-dry resin to about 2.

Abstract: A method for the manufacture of an ion exchange resin having a granular activated carbon as the matrix thereof, comprises causing a granular activated carbon to retain therein up to about 30% by weight, based on the weight of granular activated carbon, of a polymerizable solution containing monovinyl monomers and/or polyvinyl monomers in the presence of a polymerization initiator and, optionally, an organic solvent, and allowing the mixed solution as retained in the granular activated carbon to undergo polymerization in an aqueous medium and subsequently introducing therein an ion exchange group.

Abstract: A non-toxic anionic resin selected from resins having a polymeric reticulated skeleton of styrenic or acrylic type, inert to the digestive enzymes, having a molecular weight higher than 1000 and containing ionizable amino groups, resins having a cellulosic reticulated skeleton modified by the introduction of free or substituted amino groups and resins having a polysaccharide reticulated skeleton modified by the introduction of free or substituted amino groups. The resin is capable of binding itself permanently to the biliary acids and is salified with an acid corresponding to the general formula: ##STR1## wherein: R' represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, a hydroxyalkyl group having 1 to 3 carbon atoms,R represents a chlorine atom or a group selected from p-chlorobenzoyl, p-bromobenzoyl and p-fluorobenzoyl,W represents a group selected from OH, --N(R"')--CH(R")-(CH.sub.2).sub.n --COOH and O--CH.sub.

Abstract: Diesters of the formula: ##STR1## wherein R is CH.sub.3 or C.sub.2 H.sub.5 and n is 0 to 10; vinyl ether monomers derived therefrom; copolymers of the vinyl ether monomers with one or more selected perfluorinated monoolefins; articles of manufacture made from the copolymers; process for making the diesters; process for using copolymer membranes in a chlor-alkali cell.

Abstract: A novel fluorinated copolymer is prepared by copolymerization of a fluorinated olefin with a novel sulfur containing fluorinated vinyl ether of the formula: ##STR1## wherein k is 0 or 1 and l is an integer of 3 to 5, which is prepared from starting materials which are also novel. Said copolymer is useful for preparation of a fluorinated cation exchange membrane having carboxylic acid groups and/or sulfonic acid groups which can be used advantageously in electrolysis of an aqueous alkali metal halide solution with improved electrolysis performance.

Abstract: A fluorinated copolymer having ion-exchange group is produced by copolymerizing a fluorinated ethylenic unsaturated monomer and a functional monomer having a functional group of carboxylic acid group or a group which can be converted to carboxylic acid group in an aqueous medium in the presence of a polymerization initiator source and in the presence of a specific molecular weight regulator. The specific molecular weight regulator is selected from the group consisting of aliphatic alkanes alicyclic alkanes and water soluble organic solvents and controls the molecular weight without lowering the copolymerization velocity and without lowering the stability of the aqueous latex.

Abstract: New Synthetic resins useful as inert material for separating layers in ion exchanger mixed bed filters. The new synthetic resins are copolymers of(a) substituted styrenes and/or methacrylates,(b) methacrylates of polyhydric alcohols and/or aromatic polyvinyl compounds and(c) unsaturated hydrocarbons which have at least two allyl groupings in the molecule, and/or polyvinyl ethers of polyhydric alcohols, and optionally(d) styrene.

Abstract: Novel polyfunctional compounds and polymers are disclosed of the general formula ##STR1## wherein Q designates -X' or -X-.epsilon.-R; where X' designates ##STR2## where .alpha. is --OH, or --SH;.beta. is --OH, --SH, --NH.sub.2, --NO.sub.2, --CO--R.sub.2, --R.sub.2 C.dbd.N--OH, --COOH, -hal, alkyl, aryl, or aralkyl; halogen being chlorine or bromine;.gamma. is a non-interfering substituent;where .beta. and .gamma. may form together a hydrocarbyl ring system;where .delta. is --(CH.sub.2).sub.n -- or --SO.sub.2 --;where X is --O--, --S--, --NH--, --N.sup.+ R.sub.2 R.sub.3 Cl.sup.- or --P--;where.epsilon. is --(CH.sub.2).sub.n --, --SO.sub.2 --, --NH-- or --CH.sub.2 (O-CH.sub.2 --CH.sub.2).sub.n --; ##STR3## wherein the upwardly directed bonds are connected to the R polymer molecule and the downwardly directed bonds are connected to .delta. groups;n is an integer of from 1 to 15 or zero;R is a polymeric backbone, alkyl or aralkyl; andR.sub.2, R.sub.3 and R.sub.

Abstract: A basic copolymer whose main chain is cross-linked which comprises about 6 to about 98% by weight of recurring units of Formula (A) or (B), ##STR1## wherein R.sub.1, R.sub.2 and R.sub.3, which may be the same or different, each represents a hydrogen atom or a hydrocarbon group selected from the group consisting of C.sub.1-20 alkyl groups, C.sub.3-10 cycloalkyl groups, C.sub.3-8 alkenyl groups, C.sub.6-15 aryl groups, C.sub.7-12 arylalkyl groups and C.sub.1-15 aminoalkyl groups; and X is an acid radical, and about 2 to about 94% by weight of cross-linked units based on the total weight of the recurring units of Formula (A) or (B) and the cross-linked units and, if desired, up to about 92% by weight of units of a monoethylenically unsaturated monomer or a conjugated monomer based on the total weight of the recurring units of Formula (A) or (B), the cross-linked units and the units of the monoethylenically unsaturated monomer or the conjugated monomer.

Abstract: The reaction of glycidyl methacrylate (GMA) with an ionogenic methacrylate ester containing amine groups of the tertiary type such as dimethylaminoethyl methacrylate (DMAEMA) in the presence of an acidic water solution produces a new and novel water soluble, ionic, cross-linking, methacrylate bifunctional monomer wnhich is useful in the manufacture of anion exchange polymers while employing an aqueous solvent system.

Abstract: Ion exchange resins having improved physical stability and perfect bead count are prepared by a free-radical catalyzed polymerization of a monomer mixture utilizing certain peroxyester and peroxydicarbonate catalysts, followed by functionalizing the so prepared polymer.

Abstract: Fluorinated ion exchange polymers which have pendant side chains which contain --OCF.sub.2 COOR groups, or which have both pendant side chains containing carboxylic groups and pendant side chains which contain sulfonyl groups, when used in the form of membranes to separate the anode and cathode compartments of an electrolysis cell, permit operation at high current efficiency. Those containing both carboxylic and sulfonyl groups can be made by oxidation of fluorinated polymers which have pendant side chains containing sulfinic groups, or both sulfinic and sulfonyl groups. The fluorinated polymers which have pendant side chains containing sulfinic groups, or both sulfinic and sulfonyl groups, are in turn made from fluorinated polymers which have pendant side chains containing sulfonyl halide groups by reduction with, for example, hydrazine. Those polymers which have only pendant side chains which contain --OCF.sub.

Abstract: Process for preparing cation exchange resin having macroreticular structure, high surface area and lowered apparent density from a macroreticulated copolymer produced by copolymerizing a mixture of a monoethylenically unsaturated monomer and a polyethylenically unsaturated monomer dissolved in an organic liquid which is a solvent for said monomers but unable to substantially swell the resulting copolymer, and macroreticulated cation exchange resin beads produced by the process.

Abstract: Processes for making copolymers comprising treating a reaction mixture of a monomer and a substrate comprising ferromagnetic material located in a polymeric matrix so as to polymerize the monomer in a manner that it forms a polymeric shell grafted on to and surrounding the substrate, the polymerization of the monomer being initiated by adding the components of a redox system sequentially to the reaction mixture.

Abstract: A novel porous, weakly acidic, itaconic acid ion exchange resin and a process for its preparation are disclosed. The process comprises the copolymerization of the beta-monoalkyl ester of itaconic acid and a cross-linking agent such as divinyl benzene in the presence of a pore forming agent selected from the group consisting of aliphatic hydrocarbons of from 5 to 8 carbon atoms, alicyclic hydrocarbons of from 5 to 8 carbon atoms and halogenated hydrocarbons of from 1 to 3 carbon atoms, followed by hydrolysis of the resulting copolymer. The macroreticular itaconic acid ion exchange resin of this invention is characterized by an excellent combination of exchange capacity, heavy metals capturing capacity, ion exchange rate and gas adsorptive capacity.

Abstract: Ion exchange resins exhibiting increased crush strength and/or higher density are prepared from a cross-linked polymer by imbibing a halo-substituted olefin within the cross-linked polymer's structure and subsequently polymerizing the imbibed olefin. For example, imbibing vinylidene chloride within a chloromethylated, cross-linked copolymer of styrene and subsequently polymerizing the vinylidene chloride forms a high density resin, which resin is useful in the preparation of ion exchange and chelate type resins having improved crush strength.

Abstract: Making amphoteric thermally regenerable ion-exchange resins by encapsulating poly (weak acid) ion exchange particles in a matrix of a polymer of opposite ion-exchange type in the presence of certain agents which inhibit the formation of deleterious salts between the resins.

Abstract: A photographic element comprises a support having thereon a layer containing a novel polymer comprising a recurring unit having the formula: ##STR1## said element comprising a source of metal ions. The elements are useful in diffusion transfer processes, and particularly useful with chelating dyes or dye-forming materials to provide a metallized dye image.

Abstract: 1. In a process for preparing a cation exchange resin having a water-insoluble matrix and cation exchange groups bonded thereto, the improvement comprising employing as said matrix a solid copolymer of macroreticular structure which is permeated by small channels or voids into which liquids are able to penetrate, which matrix is prepared by copolymerizing a mixture consisting essentially of (1) a monovinyl carbocyclic aromatic compound or an ester of acrylic or methacrylic acid, with (2) a polyethylenically unsaturated monomer selected from the group consisting of a polyvinyl carbocyclic aromatic compound, an ester of a dihydric alcohol and an .alpha.-.beta.

Abstract: A process of removing unsaturation from resins by reaction with diimine. Thermally regenerable ion exchange resins are prepared by the hydrogenation of unsaturated polymers containing unquaternized amino groups with diimine. Procedures for generating the reactive diimine intermediate from precursors such as hydrazine are described.

Abstract: What is disclosed is a pearl polymer product, a method of making the same, and the use thereof as a carrier for biologically active materials, said product being composed of hollow pearl particles having a diameter from 5 to 1000 microns and consisting of a cross-linked polymer which is a cross-linked homopolymer or copolymer comprising at least one member selected from the group consisting of acrylamide, methacrylamide, methylene-bis-acrylamide and methylene-bis-methacrylamide, said polymer containing at least 5 percent by weight of a monomer having at least two carbon-carbon double bonds which are activated by a neighboring phenyl group or carbonyl group, said polymer further being of a composition such that x+3y.gtoreq.40, where x is the percent by weight in the polymer of acrylamide and methacrylamide and y is the percent by weight in the polymer of methylene-bis-acrylamide and methylene-bis-methacrylamide.

Abstract: A process for demineralizing an aqueous saline solution containing a deoxygenating agent by treating it with a thermally regenerable ion-exchange resin comprising a resinous material derived from a substituted diallylamine.

Abstract: An adsorbent comprising a porous copolymer produced by copolymerizing a cross-linkable monomer and a mono-ethylenically unsaturated monomer, said copolymer having pores of an average pore diameter (d) of 500 A to 6,000 A and having such a broad pore diameter distribution that the pore volume having a pore diameter in the range of from 0.5 d to 2 d is not more than 60% of the total pore volume in the copolymer. By the use of such a porous copolymer having a specific composition and pore characteristics, organic compounds (e.g. toxic compounds) adsorbed on the proteins (e.g. plasma proteins) present in intercellular and/or extracellular liquids (e.g. blood) can be effectively adsorption-removed. Especially when the present adsorbent is used for purification of blood, it is advantageously subjected to such a pretreatment that plasma proteins are adsorbed on the adsorbent and then crosslinked with a crosslinking agent.

Abstract: Hard, infusible, discrete beads of crosslinked copolymer are prepared by free-radical catalyzed polymerization of a monomer mixture in aqueous dispersion wherein oxygen is incorporated in the monomer mixture. Ion exchange resins having improved mechanical strength are obtained by attaching functional groups to the copolymer.

Abstract: What is disclosed is a pearl polymer product, a method of making the same, and the use thereof as a carrier for biologically active materials, said product being composed of hollow pearl particles having a diameter from 5 to 1000 microns and consisting of a cross-linked polymer which is a cross-linked homopolymer or copolymer comprising at least one member selected from the group consisting of acrylamide, methacrylamide, methylene-bis-acrylamide and methylene-bis-methacrylamide, said polymer containing at least 5 percent by weight of a monomer having at least two carbon-carbon double bonds which are activated by a neighboring phenyl group or carbonyl group, said polymer further being of a composition such that x+3y.gtoreq.40, where x is the percent by weight in the polymer of acrylamide and methacrylamide and y is the percent by weight in the polymer of methylene-bis-acrylamide and methylene-bis-methacrylamide.

Abstract: An ion-exchange hollow fiber is prepared by introducing into the wall of the fiber polymerizable liquid monomers, and polymerizing the monomers therein to form solid, insoluble, cross-linked, ion-exchange resin particles which embed in the wall of the fiber. Excess particles blocking the central passage or bore of the fiber are removed by forcing liquid through the fiber. The fibers have high ion-exchange capacity, a practical wall permeability and good mechanical strength even with very thin wall dimensions. Experimental investigation of bundles of ion-exchange hollow fibers attached to a header assembly have shown the fiber to be very efficient in removing counterions from solution.