Abstract: A modified polymer rubber is obtained by(1) graft-polymerizing at least one grafting monomer to a shreaded rubbery polymer (A) in an aqueous suspension at a temperature of 30.degree.-130.degree. C. to obtain a graft polymer, and(2) kneading the graft polymer with at least one polymerizable monomer in the presence of a free radical initiator at a temperature of 180.degree.-280.degree. C. This process does not cause gel formation and is advantageous in manufacturing cost.The modified polymer rubber thus obtained is excellent in processability and storage stability, and highly useful as a compatibilizer for various resins.

Abstract: A method of addition of polymerization initiator in the process of suspension polymerization or emulsion polymerization polymerizing a polymerizable monomer in aqueous medium, comprising introducing a low-temperature-active polymerization initiator taking part in the polymerization reaction to a piping system filled beforehand with water and successively adding said initiator in the piping system to polymerization system within 20 minutes using water.

Abstract: A process for preparing an elastomer-containing vinyl chloride graft copolymer having an elastomer content of up to 65% by weight. The process comprises forming a mixture of an elastomer dispersion, water, buffer and initiator, adding a precipitating agent; after precipitation has occurred, metering into the mixture the grafting monomer and a protective colloid; and then subjecting the mixture to suspension polymerization conditions. The graft copolymeric material is useful as an impact modifier or as plasticizer-free flexible PVC.

Abstract: This invention relates to a core-shell polymer which is useful for polyoxymethylene resin, a polyoxymethylene resin composition containing the core-shell polymer and a molded article made of the polyoxymethylene resin composition.The core-shell polymer comprises a rubbery polymer core and a glassy polymer shell and has substantially no detectable anion.This core-shell polymer makes the molded articles be improved on the impact strength, elongation at the weld line, etc. The molded articles is used as various products (such as gears, reels, etc.).

Abstract: A composition and method of use thereof for the treatment of wastewater comprising a block copolymer having the formula: ##STR1## wherein E is a polymeric segment obtained from the polymerization of hydrophobic monomers, x when present is a nonionic monomer, y is a cationic monomer, R.sub.1 and R.sub.2 are the same or different and are H or a lower alkyl group from C.sub.1 to C.sub.3 and F is a salt of an ammonium cation.

Abstract: Thermoplastic polyester, copolyester and polyblend molding compositions impact-modified by glycidyl methacrylate grafted EPDM exhibit high impact strength combined with good knit-line characteristics, when the grafted comonomer content exceeds 2 percent by weight in the impact modifier, it has a gel content in the range of from about 10 to about 80 weight percent.

Abstract: Covulcanizable compositions comprising (A) 55-100% by weight of an elastomeric copolymer of vinylidene fluoride with perfluoropropene optionally tetrafluoroethylene and containing from 0.001 to 2% by weight of bromine; (B) 0-45% by weight of a tetrafluoroethylene and propylene copolymer; (C) 0.7-2.5 parts for 100 parts of mix (A)+(B) of a bisphenol compound; (D) 0.3-1.5 parts for 100 parts of mix (A)+(B) of an organic guaternary compound of ammonium, phosphonium or aminophosphonium; (E) 0.4-5 parts for 100 parts of mix (A)+(B) of an organic peroxide; (F) 1-5% by weight of (A)+(B) of a peroxide cross-linking coagent.

Abstract: Polyolefin coatings and films that may be used as release sheets, processes for the manufacture thereof and the related compositions are disclosed. The release sheets are formed from a composition of polyolefin, a dimethyl polysiloxane having functional end-groups, a vinyl silane, an agent for grafting the vinyl silane onto the polyolefin and a moisture curing agent. The composition is fed to an extruder and formed into sheet, especially by feeding a mixture having two components, one having an excess of vinyl silane and the other having less than an excess of vinyl silane, based on the amount of dimethyl polysiloxane in each component. The release sheets may be used, for instance, as the backing sheet for labels.

Abstract: A heat resistant polyvinyl chloride copolymer or a heat and impact resistant polyvinyl chloride copolymer is prepared by conducting graft copolymerization of N-substituted maleimide on a vinyl chloride resin or a rubber containing vinyl chloride resin.The graft copolymerization reaction is carried out in the presence of a radical polymerizable monomer which is (1) liquid at the polymerization temperature, (2) capable of dissolving the N-substituted maleimide at the temperature, (3) 70.degree. C. or more in glass transition temperature of the polymer thereof, and (4) used in an amount sufficient to dissolve the N-substituted maleimide.

Abstract: The modified polyolefin is produced by graft-polymerizing (a) 100 parts by weight of a polyolefin, with (b) 0.01-30 parts by weight of a glycidyl compound represented by the following general formula: ##STR1## wherein R is a hydrogen atom or an alkyl group having 1-6 carbon atoms, Ar is an aromatic hydrocarbon group having 6-20 carbon atoms and containing at least one glycidyloxy group, and n is an integer of 1-4. The glycidyl compound may be added stepwise to have a higher graft ratio. The modified polyolefin may be graft-copolymerized with polyesters at a high graft ratio.

Abstract: A stable emulsion polymer is prepared by the emulsion polymerization of a vinyl monomer component in the presence of a base neutralized copolymer having a peak molecular weight not exceeding 50,000 of an olefinically unsaturated material selected from the group consisting of 1-decene, 1-dodecene, undecenylic acid and mixtures thereof and an ethylenically unsaturated anhydride containing material. The emulsion polymer is particularly useful for preparing coating compositions which have excellent physical properties.

Abstract: Process for the continuous bulk production of high impact vinylaromatic copolymers in which the vinylaromatic monomer, and if present, a comonomer selected from the group consisting of acrylonitrile, methacrylonitrile, acrylic acid, methacrylic acid and their alkyl- or cyclo-alkyl-esters containing from 1 to 8 carbon atoms in the alkyl group, the rubber, a part of the diluent solvent and the catalyst are premixed in a premixer at a temperature under 100.degree. C. and fed to a plug-flow agitated tubular reactor, which is divided into several stages or zones. The excess mixture is recycled to the premixer and the remaining part of the diluent solvent is injected into the top of the reactor to prevent the formation of incrustations. In the first zone of the reactor, the temperature and the residence time of the mixture are regulated so to have the halving the catalyst life.

Abstract: The maleimide copolymer of the invention is of the class of N-substituted maleimide copolymer such as N-alkyl or N-aromatic maleimide copolymer having peroxy bonds in a molecule, utilizable as a precursor for preparing a maleimide block copolymer and as a modifier for other resins. The maleimide block copolymer, which is useful as a molding material or a thermal resistance improver, is obtained by polymerizing maleimide monomers in the presence of a polymeric peroxide followed by polymerizing vinyl monomers.

Abstract: Polyolefin-vinyl polymer composites are produced by impregnating polyolefin particles with vinyl monomer and free radical polymerization initiator in the ratio of about 10-200 parts by weight of vinyl monomer and 0.01-4.0 parts by weight free radical polymerization initiator per 100 parts by weight polyolefin, the impregnation being effected by slowly mixing the components at room temperature or at an elevated temperature below the decomposition temperature of the free radical polymerization initiator. After the impregnation is completed, an aqueous suspension of the mixture is formed by adding the same to water in a ratio of about 100 parts by weight of mixture per 80-1000 parts by weight of water, after which the aqueous suspension is heated to a temperature sufficiently high to polymerize the vinyl monomer.

Abstract: A composition comprising (i) a copolymer of ethylene; one or more polar unsaturated alcohols, acids, or esters; and a N-substituted maleimide or (ii) a copolymer of ethylene and one or more polar unsaturated alcohols, acids, or esters grafted with an N-substituted maleimide.

Abstract: A process for preparing a grafted star polymer which comprises contacting a nitrogen-containing polymerizable organic polar compound with a star polymer (as hereinbefore defined) in the presence of a free radical polymerization initiator and characterized in that the reaction is carried out in a mineral oil solvent and, as coupling inhibitor, either a chain transfer agent, a pi-electron donor, or a comonomer, together with the modified, hydrogenated star polymers thus produced, and their use as luboil additives.

Abstract: Disclosed is a method of making graft copolymers of olefin polymers by contacting a particulate olefin polymer with a free radical polymeriztion initiator, e.g., a peroxide, and a vinyl monomer at about from 60.degree. to 125.degree. C., while controlling the monomer addition rate so that it does not exceed about 4.5 pph/min, and most preferably does not exceed about 3.0 pph/min, at any monomer feed level. To prevent polymer degradation, a non-oxidizing environment is maintained throughout the process, and residual free radicals are deactivated, and unreacted initiator is decomposed, before the graft copolymer is exposed to air.

Abstract: A polymer composition comprising a polymer or a highly saturated polymer, an organic peroxide and a maleimide derivative, said polymer being produced by radical polymerization using a sulfur-free compound as an emulsifier and a terpene type compound as a molecular weight modifier and said highly saturated polymer being obtained by hydrogenating said polymer.

Abstract: A method for the treatment of melt-grafted polypropylene to improve adhesive properties thereof is disclosed. Molten grafted polypropylene, formed by melt grafting polypropylene with an alpha,beta unsaturated carboxylic acid or anhydride, is treated in melt processing apparatus with a minor amount of an aqueous solution of an alkaline material e.g. an aqueous solution of sodium hydroxide. The thus treated grafted polypropylene is separated from the aqueous solution and recovered e.g. in the form of pellets. The melt-grafted polypropylene may be formed in the melt processing apparatus prior to treatment with the aqueous solution or polypropylene that has been grafted in a previous operation may be fed to the apparatus. The treated polymer may be used in adhesive formulations.

Abstract: Ethylene/vinyl acetate copolymers containing very high molecular weight components and having a reduced tendency to tackiness may be obtained by a further addition of ethylene during the process of solution polymerization at a moderate pressure.

Abstract: An improved method for carboxylating styrenic resins and particularly impact-modified styrenic resins such as ABS resins, by melt-processing a mixture comprising the styrenic resin, an ethylenically-unsaturated carboxylic compound, and, optionally, a free-radical generator.

Abstract: A comb copolymer consisting of a methacrylic macromonomer as a branch ingredient and acrylic ester as a backbone ingredient and being suitable for an acrylic elastomer material which is excellent in transparency, weatherability and mechanical strength; an impact resistant acrylic resin composition obtained by blending the above comb copolymer with a PMMA (co)polymer; and a comb copolymer similarly consisting of a methacrylic macromonomer as a branch component and acrylic ester as a backbone component and being an acrylic resin which is excellent in transparency, weatherability, gloss and light resistance, are disclosed in this invention.Preparation methods of the high molecular weight comb copolymers useful for molding materials comprising the above mentioned comb copolymers are disclosed.

Abstract: A process for producing a polymer crosslinkable by exposure to moisture in the presence of a hydrolysis/condensation catalyst comprising blending (i) a thermoplastic base polymer, (ii) a solid carrier polymer containing a silane, and (iii) a free radical generator; heating and mixing (i), (ii) and (iii) together at a temperature above the crystalline melting point of said base polymer; optionally, a free-radical generator, hydrolysis/condensation catalyst, and other additives are contained in the solid carrier polymer.

Abstract: A thermosetting resin composition comprising(A) 60 to 95% by weight of a prepolymer or precopolymer selected from the group consisting of (A-1), (A-2) and (A-3) below,(A-1) a prepolymer of diallyl phthalate,(A-2) a precopolymer of diallyl terephthalate derived from diallyl terephthalate of the following formula (1) ##STR1## and an aromatic benzyl hydrocarbon having at least one hydrogen atom at the benzyl position and represented by the following formula (2) ##STR2## wherein each of R.sup.1 and R.sup.2 represents a member selected from the class consisting of a hydrogen atom and lower alkyl groups, and n is an integer of 1 to 3, and(A-3) a mixture of (A-1) and (A-2), and(B) 40 to 5% by weight of a polyacrylate or polymethacrylate of dipentaerythritol having at least 4 acryloyl or methacryloyl groups in the molecule and represented by the following formula ##STR3## wherein each R.sup.3 represents a hydrogen atom, --COCH.dbd.CH.sub.2 or ##STR4## and at least four R.sup.3 groups represents --COCH.dbd.CH.sub.

Abstract: This invention relates to a process for the catalytic grafting of an ethylenically unsaturated monomer onto a copolymer in the presence of a catalyst. The monomer is selected from the group consisting of ethylenically unsaturated carboxylic acids, anhydrides esters and other derivatives thereof. The copolymer is selected from the group consisting of certain copolymers of ethylene and ionomers of such copolymers. The catalyst is a mixture of (a) a certain amount of water and (b) at least one of certain phosphorus-containing compounds. The process comprises admixing copolymer, monomer, catalyst and an organic peroxide at a temperature above the melting point of the copolymer for a period of time so as to obtain a uniform distribution of monomer, catalyst and peroxide in the copolymer. The resultant grafted copolymer has improved color, and is useful in adhesive systems and as a compatibilizer for polymers and other materials.

Abstract: To produce a graded index polymer there is diffused into a base material formed of at least one partly polymerized monomer adapted to yield a homopolymer with refractive index N1 in the gel state an additive material formed of at least one monomer adapted to yield a homopolymer with refractive index N2 different from N1. The polymerization of the base material treated in this way is then completed. The additive material comprises a mixture of at least two monomers and the composition of this mixture is varied with time.

Abstract: The present invention relates to a process for modifying or crosslinking polymers by the use of novel co-agents in the reaction of polymers with organic peroxides. The novel co-agents comprise oligomers of dialkenyl substituted aromatic compounds, preferably oligodiisopropenylbenzene.

Abstract: An improved method for carboxylating styrenic resins and particularly impact-modified styrenic resins such as ABS resins, by melt-processing a mixture comprising the styrenic resin, an ethylenically-unsaturated carboxylic compound, and, optionally, a free-radical generator.

Abstract: A process for producing a toner resin by a two-step suspension polymerization process, which entails preparing a polymer of high molecular weight having a weight average molecular weight of greater than about 350,000 from at least one monomer having a polymerizable vinyl group using a compound having at least three t-butyl peroxide groups in one molecule, as a polymerization initiator, and then preparing a low molecular weight polymer in the presence of the high molecular weight polymer. A toner having an excellent fixing property and offset resistance can be obtained from the above resin.

Abstract: A process to graft epoxy containing functional monomers to a base polymer is provided, the process comprising the steps of: providing a melt of a base polymer; containing the melt of the base polymer with a functional monomer in the presence of a free radical initiator at a temperature of less than 240.degree. C., the functional monomer comprising alpha-beta ethylenic unsaturation and an epoxy group; and recovering an epoxy functionalized polymer. Grafting the epoxy containing monomer to the base polymer at temperatures of 240.degree. C. and less results in a low level of hydrolyzed epoxy groups.

Abstract: This invention relates to plastoelastomeric polyolefinic compositions comprising an intimate mixture of the following components, in the indicated percentages by weight:A) 10-50% of non cross-linked polypropylene;B) 2-10% of ethylene/propylene/(diene)non cross-linked elastomeric copolymer,C) 30-40% of polymeric product which is insoluble in xylene at 135.degree. C., comprising polypropylene and ethylene/propylene/(diene) copolymer, andD) 5-58% of an extender oil.This invention also relates to a process for preparing the above compositions, which consists in subjecting to vulcanization under dynamic conditions a mixture comprising, in % by weight:A) 20-80% of polypropylene,B) 80-20% of ethylene/propylene/(diene) elastomeric copolymer,C) 0.1-10%, referred to such copolymer, of a peroxide,D) 5-60%, referred to such peroxide, of a furan derivative as a cross-linking coadjuvant.and in adding, after vulcanization, the extender oil in an amount ranging from 6 to 100% calculated on the vulcanized product.

Abstract: A method of producing a modified polypropylene comprising the step of graft-polymerizing a propylene random copolymer containing an unconjugated diene comonomer represented by the general formula: ##STR1## wherein R.sub.1 -R.sub.4 are H or an alkyl group having 1-6 carbon atoms, and n is an integer of 1-20, with a monomer having an unsaturated bond by a radical method.

Abstract: A comb copolymer consisting of a methacrylic macromonomer as a branch ingredient and acrylic ester as a backbone ingredient and being suitable for an acrylic elastomer material which is excellent in transparency, weatherability and mechanical strength; an impact resistant acrylic resin composition obtained by blending the above comb copolymer with a PMMA (co)polymer; and a comb copolymer similarly consisting of a methacrylic macromonomer as a branch component and acrylic ester as a backbone component and being an acrylic resin which is excellent in transparency, weatherability, gloss and light resistance, are disclosed in this invention.Preparation methods of the high molecular weight comb compolymers useful for molding materials comprising the above mentioned comb copolymers are disclosed.

Abstract: A modified copolymer rubber obtained by kneading at 200.degree.-280.degree. C.(A) at least one copolymer rubber material selected from the group consisting of an ethylene-.alpha.-olefin copolymer rubber having a number-average molecular weight of 10,000-100,000 and an ethylene content of 15-85% by weight and an ethylene-.alpha.-olefin-nonconjugated diene copolymer rubber having a number-average molecular weight of 10,000-100,000, an ethylene content of 15-85% by weight and a nonconjugated diene content of 3.0% by weight or less,(B) a free-radical initiator,(C) at least one vinyl aromatic monomer and(D) an unsaturated dicarboxylic anhydride, wherein the weight ratios of (B):(A), (C):(A), (D):(A) and (C):(D) are 0.005-1.0:100, 0.2-20:100, 0.5-15:100 and 0.1-3:1, respectively.The process is suited for industrially producing a modified copolymer rubber having a high bound unsaturated dicarboxylic anhydride content, a low tendency of increase of the Mooney viscosity [ML.sub.1+4 (121.degree. C.

Abstract: A free-radical initiated process for preparing fluorinated polymers wherein at least one gaseous fluoroolefin is polymerized in a stirred polymerizer, the improvement comprising preparing a non-volatile polymeric seed in a reaction zone separate from the polymerizer by decomposing initiator in the presence of fluoromonomer to form oligomeric free radicals and condensing said radicals onto previously prepared polymer; and conveying said non-volatile seed to the polymerizer.

Abstract: A graft copolymer is provided. The copolymer comprises a poly-alpha-olefin base polymer that does not undergo substantial crosslinking under polymer melt conditions in the presence of a free radical initiator, having grafted thereto a monomeric 2-alkenyl azlactone. The graft copolymers exhibit desirable thermoplastic, melt flow, and adhesion properties and are particularly useful for immobilizing proteins.

Abstract: An epoxy functionalized copolymer and/or interpolymer rubber prepared in a bulk reaction for use as a modifier for improving the impact and knitline strength of thermoplastic resins.

Abstract: The present invention relates to a process for the functionalization, and preferably the maleation of a polyolefin, preferably polypropylene, by use of a selected class of peroxides which will not cause the molecular weight of the polyolefin to significantly degrade. The class of peroxide initiators which are capable of successful use in the present invention may be more broadly classified as peroxides which have radical fragments when the peroxide is dissociated, which are a combination of R.multidot. and R0.multidot., where R is an aliphatic hydrocarbon, and 0 is oxygen. The preferred peroxide initiators for use in carrying out the present invention so as to obtain the results indicated above are t-butyl peroxypivalate and isononanoyl peroxide. The composition resulting from the practice of the process of the invention is a maleated polypropylene in which the polypropylene has more than 0.3 weight percent grafted maleic anhydride and preferably greater than 0.4 weight percent, for example, from 0.

Abstract: A curable composition contains:(a) a vinyl chloride plastisol,(b) a diene acrylonitrile copolymer containing activated vinyl groups which are capable of undergoing free radical initiated polymerization carried out either by use of heat or ultraviolet light or electron beam in the presence of a free radical initiator and organometallic accelerator combination, and(c) an organometallic accelerator and free radical initiator combination adapted to promote cure of the fusing plastisol composition. The curable composition is characterized in that for every 100 parts of vinyl chloride plastisol there are present from about 9 parts to about 16 parts of diene acrylonitrile copolymer containing activated vinyl groups.The curable composition is especially suitable for use as an adhesive or sealant.

Abstract: Disclosed is a polymer alloy consisting essentially of a composition of a polyphenylene ether, a crystalline propylene resin, and an alkenyl aromatic monomer modified propylene-dialkenylbenzene compound copolymer. The composition excels in heat resistance and resistance to oils.

Abstract: Process for preparing impact-resistant translucent rubber-modified polystyrene by polymerizing compounds of the styrene class in the presence of a rubber containing thiol groups.

Abstract: A process is described for the preparation of a polymer which contains, besides polymerized units of vinyl chloride, 30 to 60% by weight, relative to the polymer, of polymerized units of an acrylate, if appropriate together with copolymerizable monomers. The acrylate is firstly polymerized in aqueous emulsion with addition of a monomer containing at least 2 ethylenically unsaturated, non-conjugated double bonds in the presence of a fatty acid salt and in the presence of an alkane- or alkylarylsulfonate. Polymerization in aqueous suspension is then carried out in which vinyl chloride, customary polymerization auxiliaries, a precipitant for the emulsifiers used in the emulsion polymerization, and water are initially introduced, and the acrylate dispersion produced by emulsion polymerization is subsequently added. Polymers of high bulk density and good free-flowing properties which can easily be demonomerized are thus obtained.

Abstract: Thermoplastic polyester, copolyester and polyblend molding compositions impact-modified by glycidyl methacrylate grafted EPDM exhibit high impact strength combined with good knit-line characteristics, when the grafted comonomer content exceeds 2 percent by weight in the impact modifier, it has a gel content in the range of from about 10 to about 80 weight percent.

Abstract: A composition providing a two-part adhesive consists of an acrylate monomer and perester catalyst, comprising the polymerizable part, and a ferric ion-accelerated butyraldehyde/aniline activator comprising the other.

Abstract: The improvement of toughness and impact strength of polyester resins is achieved by blending 60-90 parts by weight of the polyester with 10-40 parts by weight of an ethylene, propylene, diene rubber, having 2-20 unsaturated C.dbd.C linkages per 1000 carbon atoms and which has been grafted with glycidyl methacrylate to a level of 1-10 percent by weight.

Abstract: A polymerization process is provided for producing a terminally functional polymer which comprises introducing a monomer charge, a Lewis acid and an organic peroxy compound into a suitable reaction vessel and polymerizing the monomer charge at a temperature of from about 0.degree. to about -80.degree. C. to form the terminally functional polymer, wherein the monomer charge comprises isobutylene and the organic peroxy compound is charged in an amount of from about 10.sup.-4 to about 10.sup.-1 moles per mole of the isobutylene. In a preferred embodiment, the monomer charge additionally comprises vinylidene aromatic or diolefin monomers. In another preferred embodiment the monomer charge comprises the sequential addition of isobutylene and vinylidene aromatic or diolefin monomers. In a further preferred embodiment said reaction vessel is additionally charged with an electron door having an electron door number of from about 22 to about 50 the amount of said electron door being from about 10.sup.-4 to about 10.

Abstract: A process for producing monodispersed fine particles of a vinyl polymer is disclosed, which comprises polymerizing monomers containing at least one vinyl monomer selected from the group consisting of aromatic vinyl compounds, acrylic esters, and a methacrylic ester in the presence of (1) a surface active agent represented by formula (I) ##STR1## wherein R.sub.1 and R.sub.2, which may be the same or different, each represents a substituted or unsubstituted alkyl group having from 4 to 8 carbon atoms, a substituted or unsubstituted phenyl group, or a substituted or unsubstituted cyclohexyl group and M represents an alkali metal, (2) from 10.sup.-3 to 10.sup.-1 mol/l of a persulfate as a polymerization initiator, and (3) from 10.sup.-4 to 10.sup.-2 mol/l of a divalent metal sulfate as an electrolyte. Monodispersed vinyl polymer fine particles having a particle size of 1 .mu.m or greater with a very narrow size distribution are obtained.

Abstract: Grafting of maleic anhydride, possibly together with styrene, on olefinic polymers, carried out in the presence of radical starters, characterized in that one operates with the polymer maintained in suspension of either an aliphatic, cycloaliphatic or aromatic ketone, containing from 3 to 22 carbon atoms.

Abstract: Resin compositions obtained by causing copolymerization of particular radical (co-and/or) polymerizable organic peroxide and vinyl monomer in particular propylene polymers and that it is a best way to use an aqueous suspension in the manufacture.

Abstract: Dispersion polymers composed of latex, which have on the particle surface a copolymer composed of monomers having terminal acetals of the formula ICH.sub.2 .dbd.CR.sub.1 --CO--NH--(CH.sub.2).sub.n --CH(OR.sub.2) (OR.sub.3) Iin whichn=1-6;R.sub.1 =H or CH.sub.3, andR.sub.2 and R.sub.3 are identical or different withR.sub.2 and R.sub.3 =--(CH.sub.2).sub.m --CH.sub.3 (m=0-7) orR.sub.2 and R.sub.3 =--CXYZ, X, Y and Z being (CH.sub.2).sub.p --CH.sub.3 and p being 1-3, with X, Y, Z being identical or different,and betaine compounds of the formula IICH.sub.2 .dbd.CR--(CH.sub.2).sub.a --(CO--X).sub.b --Z--(CH.sub.2).sub.c --Y IIwithR=H or CH.sub.3,X=--NH or --0,Y=SO.sub.3.sup.- or COO.sup.- ##STR1## a=0-6, b=0-1,c=1-12,are very suitable for the preparation of biologically active latex reagents which have a particularly high detection sensitivity and stability.