Abstract: This invention provides a novel catalyst composed of a complex of an organic acid or its ester and a Lewis acid, preferably boron trichloride that can add olefin monomers to increase the molecular weight of the complex from as low as 200 to in excess of a million, with the complex being active viz., living, until the complex dies, viz., is decomposed or destroyed so that polymers in the liquid or easily liquefiable range of 300 to about 10,000 can be made of those more difficult to be liquefied or unliquefiable, viz., those of over 10,000 up to 100,000 or in some cases 500,000 and then those in the range of the elastomers, or moldable or extrudable plastics range having very high molecular weights, generally in excess of 100,000 up to in excess of 500,000 and having useful end groups such as the halogens and specifically chloride, allyl, acryl or methacryl, acetate or formate to name some of the more useful ones.

Abstract: This invention relates to thermostable thermoplastic moulding compounds consisting of a thermoplastic aromatic polycarbonate resin, a graft polymer and optionally a thermoplastic vinyl polymer wherein the graft or vinyl polymer is emulsion polymerized with an emulsifier which is the reaction product of 2 mols of certain carboxylic anhydrides and 1 mole of certain diols.

Abstract: An electrophotographic toner composition is provided. It contains a vinyl polymer having a number average molecular weight of 1,000-10,000, a weight average molecular weight/number average molecular weight ratio of 41-200, a glass transition temperature of 50.degree.-70.degree. C., and specific shear rates at 110.degree. C. and 190.degree. C. respectively. The toner composition affords vivid copy marks even when used in a small amount, and exhibits good fixing property even at low temperatures.

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: 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: A method for producing a propylene-.alpha.-olefin block copolymer, which comprises polymerizing propylene in the presence of a catalyst and then polymerizing in a gas phase an .alpha.-olefin other than propylene, or propylene and other .alpha.-olefin without deactivating the catalyst, wherein at least one compound selected from the group consisting of an aromatic carboxylic acid ester, a phosphorous ester, an unsaturated dicarboxylic acid diester, an amine compound and an amide compound, is supplied to the latter gas phase polymerization system.

Abstract: A process for producing a hydrophilic group-containing macromonomer having an ethylenically unsaturated group at the end thereof comprising reacting a hydrophilic group-containing polymer having a carboxyl group at the end thereof, with an ethylenically unsaturated group-containing epoxy compound in the presence of a hydrophilic organic solvent. According to the process of the present invention, there is provided a process for producing a hydrophilic group-containing macromonomer having an ethylenically unsaturated group at the end thereof which has been not known in the prior art.

Abstract: Block copolymers compose a polyisobutylene rubbery soft segment of M.sub.n of about 5,000 to above 500,000 and glassy hard segments of M.sub.n of about 5,000 or higher and usually about 10,000 to 35,000 or more, are made by preparing a living polymer block of the polyisobutylene and then polymerizing on said living polyisobutylene block the glassy hard segments by adding thereto an electron donor having a donor number of 15 to 50 and then adding and polymerizing the monomers for the glassy hard segments. The monomers for the glassy hard segments are styrene and its derivatives and indene and its derivatives and mixtures thereof.

Abstract: Thermoplastic resin compositions are blended with a novel silicone-based flame retardant which also imparts good impact resistance and low temperature ductility on the thermoplastic resins. Polyorganosiloxanes are grafted with vinyl-based polymers, such as bromostyrenes, capable of exhibiting flame retarding properties and then blended with normally flammable thermoplastic resins.

Abstract: Thermoplastic molding compositions are provided which comprise a polycarbonate resin alone or in combination with a saturated polyester resin and/or a poly(etherester) elastomer, a poly(etherimide ester) elastomer or a mixture thereof; a polyphenylene ether resin and a saturated polyester resin; a polyphenylene ether resin, a saturated polyester resin and a polycarbonate resin; or mixtures thereof modified with multi-stage polyorganosiloxane/polyvinyl-based graft polymers which exhibit markedly improved impact strength and weld line strength with no tendency to delaminate or to show mottled surfaces after molding.

Abstract: An .alpha.-methylstyrene/acrylonitrile copolymer obtainable by emulsion polymerization which, in combination with other polymers, particularly PVC, enables alloys of outstanding thermal stability and color stability to be produced and, in addition, has a high heat distortion temperature and shows good fogging behavior and which is obtained by radically initiated inflow copolymerization of a mixture of 30 to 32 parts by weight acrylonitrile and 68 to 70 parts by weight .alpha.-methylstyrene in the presence of an emulsifier containing carboxyl groups. The polymerization is conducted in such a way that a seed latex of the same copolymer or of an analogous copolymer is introduced before addition of the monomers is commenced, the reaction temperature is kept between 75.degree. and 82.degree. C. and the molar ratio of emulsifier to initiator is between 4 and 6.

Abstract: An adhesive composition comprising a component which is polymerizable or cross-linkable with a peroxy initator, e.g., a (meth)acrylic ester monomer, thiolene resin, or tough acrylic copolymer, and an initiator of the formula: ##STR1## wherein: R.sub.1 is H or lower alkyl; and R.sub.2 is H or --OR.sub.3, where R.sub.3 is H or lower alkyl.An appertaining method of bonding substrates, and bonded articles formed thereby, are also disclosed. The adhesive composition of the invention is particularly advantageous in bonding of metal substrates, on which the maleic acid peroxy compounds of the invention produce surface bonding enhancement of the adhesive composition, relative to the use of conventional polymerization/crosslinking peroxy initiators such as t-butyl perbenzoate.

Abstract: A vulcanizable fluororubber composition which comprises:(a) a fluorine-containing elastomeric copolymer of vinylidene fluoride with at least one other ethylenically unsaturated monomer copolymerizable therewith;(b) an organic peroxide;(c) a polyfunctional compound;(d) at least one member selected from the group consisting of bivalent metal hydroxides and bivalent metal oxides; and(e) an organic base.

Abstract: A surface-active block copolymer which comprises chemically linked polymeric blocks (A) and (B), block (A) of said copolymer consisting of at least one homo- or copolymerized non-polar alpha,beta-ethylenically unsaturated monomer and block (B) of said copolymer is derived by polymerizing an alpha-beta ethylenically unsaturated monomer containing an epoxy group and transforming the epoxy group into an hydroxy-substituted ionic group, preferably an anionic group. These block copolymers are used as dispersing agents in aqueous dispersions, including polymeric latex dispersions, and as plasticizing agent in hydrophilic colloid layers, including colloid layers containing a dispersed light-sensitive silver halide emulsion or other auxiliary substances for photographic materials.

Abstract: A process for extruding a hydrolyzable particulate thermolastic copolymer coated with an organic peroxide, which, under extrusion conditions, will provide essentially no crosslinking per se, but will decompose to provide a silanol condensation catalyst, including passing the coated copolymer through an extruder having a die at about its downstream end with the proviso that the extruder is operated under such conditions that (i) the temperature of the extruder before the die is maintained at a level sufficient to extrude the copolymer, but below the decomposition temperature of the organic peroxide; (ii) the temperature of the extruder at or after the die is maintained at or above the decomposition temperature of the peroxide; and (iii) there is sufficient moisture in the environment to crosslink the copolymer in the presence of a silanol condensation catalyst.

Abstract: Macromonomer prepared by contacting and reacting a polymer (oligomer) having at least three monomer repeat units and at least one silyl ether group, in the presence of an anion catalyst, with a terminally unsaturated acyl fluoride or sulfonyl fluoride.

Abstract: Composition for polymerization of ethylenically unsaturated monomer with initiator of perester salt of maleic acid and bisulfite activator in water-in-oil emulsion form.

Abstract: Polymerization of methyl methacrylate with initiator of perester salt of maleic acid is faster and better by providing bisulfite activator in water-in-oil emulsion form.

Abstract: A linear alternating polymer of carbon monoxide and at least one ethylenically unsaturated hydrocarbon exhibits improved thermal stability as evidenced by reduced weight loss at elevated temperatures and enhanced crystallinity and crystallizability when produced with a catalyst composition formed from preformed palladium trifluoroacetate and a bidentate phosphine ligand.

Abstract: A process for the production of .alpha.-olefin block copolymer particles having excellent impact resistance at low temperature and excellent molding and processing characteristics, is disclosed. The process includes a two step gas phase polymerization procedure under specific conditions in the presence of a specific catalyst system.

Abstract: A rubber composition suitable for tire treads having well-balanced excellent wet skid characteristic, ice skid characteristic and rolling characteristic, and an excellent processability, which comprises a rubber component containing at least 20% by weight of a block copolymer consisting essentially of a block A and a block B, obtained by conducting polymerization of an aromatic vinyl compound and a conjugated diene compound in a hydrocarbon solvent in the presence of an organolithium initiator and modifying with a coupling agent, and satisfying the following conditions (A) to (E);(A) the block A having a content of an aromatic vinyl compound of at most 5% by weight and a content of 1,2-bonds in the conjugated diene component of at least 10% by weight,(B) the block B having a content of an aromatic vinyl compound of 25 to 50% by weight and a content of 1,2-bonds in the conjugated diene component of at least 10% by weight,(C) a content of the block A in the block copolymer being from 20 to 80% by weight,(D) a c

Abstract: A process for preparing a crosslinked polymer comprises reacting a polycyanoacetic functional monomer or polymer with a poly .alpha.,.beta.-unsaturated ester in the presence of a catalytically effective amount of a metallic catalyst. A crosslinked polymer produced by this process is also described.

Abstract: Large acrylic star polymers containing multifunctional monomers in the core are made by group transfer polymerization techniques, preferably by arm-first, core-first, or arm-core-arm approaches.

Abstract: The invention relates to a composition comprising(A) 64-4 parts by wt. of a bismaleimide compound, or an isomaleimide isomer thereof, a maleimide-amide compound or an isomaleimide isomer thereof and maleic anhydride compound,(B) 7-77 parts by wt. of one or more ethylenically unsaturated compounds containing 5-50 C-atoms and is characterized in that the composition further comprises(C) 3-60 parts by wt. of one or more compounds from the group of hydroxy-alkylacrylates or amino-alkylacrylates,(D) 1-20 parts by wt. of one or more terminally functional polymers as flexibilizer, with the proviso that the sum, of parts of compounds A, B, C and D amounts to 100.

Abstract: A pourable polyvinyl chloride having an acrylate content of at least 30 percent by weight, is formed through a process wherein the emulsion polymerization of an acrylic acid ester forming soft polymers is conducted together with a diene crosslinking agent(a) in the presence of a fatty acid soap, or(b) by the batchwise or continuous addition of the monomer, pre-emulsified with an aqueous alkali lauryl sulfate solution, during polymerization, and by the addition of a fatty acid soap after polymerization, and the vinyl chloride polymerization is performed in the presence of a methylcellulose ether as the suspension agent; wherein, after addition of the suspension agent, a Ca(OH).sub.2 suspension is added, the polymerization charge is neutralized by addition of an acid, and then an organic peroxide is added as the initiator in a dissolved or suspended form. The polymerization can also take place without acid addition, by utilizing azo-type catalysts.

Abstract: Graft copolymers are prepared by means of a two-step polymerization process, in emulsion: in the first step, a vinylaromatic monomer and an acryl or metacryl monomer are grafted on a monomodal polybutadiene latex constituted of particles of diameter comprised within the range of from 800 to 2500 .ANG.. The polymerization/grafting reaction is continued up to a 70-90% conversion, at which time a further portion of monomodal polybutadiene is added, together with further amounts of said monomers, always in emulsion.

Abstract: A process for modifying the surface characteristics of a pre-formed polymeric substrate to impart hydrophilicity, hydrophobicity, or other desired properties thereto, by peroxidizing the surface of the substrate and then allowing the active sites along the polymer chains to generate free radicals which induce graft polymerization of a suitable ethylenic monomer (or other ethylenically-unsaturated compound) onto the surface of the substrate is described. Such graft copolymerization is undertaken in the presence of variable valence metal ions in a reduced state under acidic conditions and at selected reaction times and relatively low temperatures, and ideally in the presence of squarate ions (diketocyclobutenediol) to control the physical characteristics of the surface graft and to restore the metal ions to their lower valence state without at the same time producing deleterious by-products.

Abstract: Two stage film-forming polymers having a soft first and a hard second stage are prepared by emulsion polymerizing the first stage and then, in the presence of a coalescent, the second stage. The polymers combine low MFT with superior early block resistance and high temperature hardness.

Abstract: A thermoplastic resin having an excellent thermal stability and a high heat resistance is prepared by initiating polymerization of 65-85 parts by weight of a monomer mixture (A) consisting of 50-85% by weight of .alpha.-methylstyrene, 3-20% by weight of methyl methacrylate, 2-20% by weight of acrylonitrile, and 0-25% by weight of an aromatic alkenyl compound other than .alpha.-methylstyrene, continuously or intermittently adding, on the way of the polymerization, 2-15 parts by weight of a monomer (B) consisting of acrylonitrile or a mixture thereof with an aromatic alkenyl compound other than .alpha.-methylstyrene to the polymerization system while continuing the polymerization, further adding to the polymerization system 5-25 parts by weight of a monomer (C) consisting of an aromatic alkenyl compound other than .alpha.

Abstract: Novel bis-(silylethyl)-oligosulphides are obtained by reacting a vinyl silane of the formula (CH.sub.2 .dbd.CH).sub.m --SiR.sub.n.sup.1 R.sub.4--(m+n) in which R represents chlorine, bromine, iodine, C.sub.1 --C.sub.3 -alkoxy, 2-methoxyethoxy, 2-ethoxyethoxy or hydroxy, R.sup.1 represents C.sub.1 --C.sub.3 -alkyl, phenyl or C.sub.5 --C.sub.7 -cycloalkyl, n is 0, 1 or 2, m is 1 or 2 and m+n is 1, 2 or 3 with sulphur as well as in a given case hydrogen sulphide in molar ratios of vinyl silane to sulphur of from 1:2.5 to 1:10 and vinyl silane to hydrogen sulphide of from 1:0 to 1:5 at temperatures between about 100.degree. and 200.degree. C. under pressure of from 1 to 25 bars (total pressure at the reaction) temperature) and in the presence of sulphidation catalysts known per se, in a given case followed by hydrolysis or partial hydrolysis of the reaction products.

Abstract: A process for modifying a rubber, which comprises reacting a rubber having an unsaturated carbon linkage with an organic compound having a carboxyl group and an aldehyde group in the presence of an acid catalyst.

Abstract: A modified rubber composition comprising a blend of (a) a modified rubber obtained by reaction a rubber having an unsaturated carbon linkage with an organic compound having a carboxyl group and an aldehyde group in the presence of an acid catalyst, and (b) carbon black.

Abstract: The present invention provides an improved process for preparing a polyolefin cross-linked by silane linkage by contacting a polyolefin modified with silane with water in the presence of a silanol condensation catalyst, the improvement comprising said polyolefin modified with silane being a reaction product produced by reacting an ethylene/.alpha.-olefin copolymer having a density of from 0.850 to 0.910 with a silane compound in the presence of a free radical generating agent, said ethylene/.alpha.-olefin copolymer being prepared by copolymerizing ethylene with an .alpha.-olefin having 3 to 12 carbon atoms in a vapor phase with substantially no solvent present and in the presence of a catalyst comprising an organoaluminum compound and a solid substance containing magnesium, and a metal selected from the group consisting of titanium, vanadium and mixture thereof.

Abstract: Novel stable anaerobic compositions are prepared which contain, as a novel reactive thickener, a polymerizable polymeric adduct having pendant double bonds which is dissolved in a polymerizable monomeric diluent. The anaerobic compositions show improved performance properties. The thickener is prepared by reacting an anhydride-containing polymer with an excess of a C.sub.2 -C.sub.5 hydroxyalkyl acrylate or methacrylate (e.g. hydroxyethyl and hydroxypropyl methacrylate), optionally in the presence of (meth)acrylate monomers which are not reactive with the anhydride groups of the polymer and which act as an additional diluent. The polymer may be prepared by conventional free radical polymerization techniques using maleic, citraconic, and/or itaconic anhydride and an ethylenically unsaturated monomer (e.g. C.sub.1 -C.sub.10 alkyl acrylates or methacrylates or styrene).

Abstract: A process for polymerizing a styrene monomer or a styrene monomer having a rubber-like polymer dissolved therein by using, as the catalyst, an organic peroxide of the formula ##STR1## where R.sub.1 and R.sub.2 are the same or different radicals selected from the group consisting of hydrogen, alkyl radicals of from 1 to 5 carbon atoms, and phenyl. Preferably, the polymerization is continuously carried out by bulk or solution polymerization while the reaction mixture present in the polymerization zone is kept in such a mixed state as to make it substantially homogeneous.

Abstract: A process for the production of modified polypropylene particles by polymerizing vinyl monomers in aqueous suspension wherein (a) an aqueous suspension is prepared which, based on 100 to 2000 parts by weight of water, contains 100 parts by weight of polypropylene particles, 4 to 30 parts by weight of a polar vinyl monomer and based on 100 parts by weight of the monomer, 0.1 to 10 parts by weight of a radical chain polymerization initiator which has a half life of at least 2 h at a temperature of 80.degree. to 135.degree. C. and 10 to 1200 parts by weight of an organic solvent which is capable of swelling polypropylene, of which the boiling point at 760 Torr is at least 100.degree. C. and which is miscible with the monomers in any proportion; (b) the aqueous suspension is heated without decomposition of the initiator, the polypropylene being swollen and the monomer penetrating into the polypropylene, after which (c) the aqueous suspension is kept at temperatures of .gtoreq.85.degree. C.

Abstract: The invention relates to a process for preparing terpolymer polyblends having high gloss and ductility in formed articles, wherein, rubber particles in an aqueous latex are reacted with an alkenyl aromatic, alkenyl nitrile and alkyl acrylate monomer formulation such that said rubber particles become grafted with at least a portion of said monomers while said monomers form a matrix terpolymer phase of said monomers followed by separating said matrix phase terpolymer and said grafted rubber particles from said latex as a terpolymer polyblend. The invention also relates to a composition of said process.

Abstract: New compositions and a process for the preparation of conjugated diene polymers of broadened molecular weight distribution by reacting non-terminated lithium catalyzed conjugated diene polymers with cyclic organic compounds selected from the group of carbonates, thiocarbonates and sulfites. The resulting new compositions are suitable for use in making high impact plastics and for fabricating rubber goods.

Abstract: New compositions and a process for the preparation of conjugated diene polymers of broadened molecular weight distribution by reacting non-terminated lithium catalyzed conjugated diene polymers with linear organic compounds selected from the group of carbonates, thiocarbonates and sulfites. The resulting new compositions are suitable for use in making high impact plastics and for fabricating rubber goods.

Abstract: Novel chemical compounds, copolymers of vinyl acetate, ethylene and peroxy alkyl acrylate having the following general formula: ##STR1## wherein R.sub.1 represents a normal alkyl, --CH.sub.3, --C.sub.2 H.sub.5, --C.sub.3 H.sub.7, --C.sub.4 H.sub.9, or --C.sub.5 H.sub.11 ;R.sub.2 represents ##STR2## x=24.0 to 89.9 mole %; y=10.0 to 75.0 mole %;z=0.1 to 1.0 mole %.

Abstract: A process for modifying the surface characteristics of a pre-formed polymeric substrate to impart hydrophilicity, hydrophobicity, or other desired properties thereto, by peroxidizing the surface of the substrate and then allowing the active sites along the polymer chains to generate free radicals which induce graft polymerization of a suitable ethylenic monomer (or other ethylenically-unsaturated compound) onto the surface of the substrate is described. Such graft copolymerization is undertaken in the presence of variable valence metal ions in a reduced state under acidic conditions and at selected reaction times and relatively low temperatures, and in the presence of squarate ions (diketocyclobutenediol) to control the physical characteristics of the surface graft and to restore the metal ions to their lower valence state without at the same time producing deleterious by-products.

Abstract: What is disclosed are a method for making a transparent impact-resistant polymer comprising a rubbery phase of grafted polybutadiene and a hard copolymer phase, which polymer is adaptable to use as a molding material, which method comprises:(1) in a first polymerization stage, dissolving a solid polybutadiene rubber in a monomer mixture comprising (a) methyl methacrylate, (b) styrene, and (c) at least one of methyl acrylate or ethyl acrylate to give a solution containing from 3 to 10 percent by weight of said rubber, and then polymerizing the solution using an initiator promoting graft copolymerization and in the presence ab initio of a chain transfer agent until an amount of said monomer mixture which is one to two times the weight of said polybutadiene rubber introduced is converted, said monomers (a), (b), and (c) being present in said monomer mixture in a ratio by weight of (73.+-.5): (22.+-.2); (5.+-.

Abstract: A process for producing a graft-polymer comprises adding an aqueous solution of a salt of a strong acid and a monovalent strong base, which solution has been adjusted to a pH value of 8 to 13, to a rubber latex containing diene rubber particles and a fatty acid soap as an emulsifying agent to coagulate the above mentioned rubber particles, and thereafter adding a vinyl monomer to the latex containing the coagulated rubber particles to graft-polymerize the vinyl monomer.According to this process, the formation of rubber masses and macroparticles during the coagulation is reduced and a rubber latex containing rubber particles having a narrow range of particle size distribution is obtained. When a graft-copolymer obtained by using the latex is blended with thermoplastic resins such as vinyl chloride resins, the impact resistance of the thermoplastic resins can be remarkably improved without impairing their transparency and gloss.

Abstract: A dry grafting method of grafting a vinyl monomer onto a polymer, which method comprises admixing into an essentially dry, solvent-swollen, finely-divided, particulate, solid, polymer admixture, wherein the polymer has free radicals formed thereon and the admixture is essentially free of a polymerization initiator, a small grafting amount in incremental portions of a vinyl-monomer material to be grafted onto the swollen polymer, the amount of vinyl monomer sufficient to maintain an essentially free-flow, stirrable, particulate admixture, and effecting grafting of the vinyl monomer to the polymer.

Abstract: A process for the preparation of modified poly-N-vinylpyrrolid-2-one containing two identical reactive groups, wherein polyvinylpyrrolidone is treated with complex hydrides, with or without further reaction of the modified polyvinylpyrrolidone with a reactive bifunctional compound, to give a polymer which has a molecular weight at least 2.5 times as great as that of the starting polymer.

Abstract: A process for the preparation of modified poly-N-vinylpyrrolid-2-one containing two identical reactive groups, wherein polyvinylpyrrolidone is treated with complex hydrides, with or without further reaction of the modified polyvinylpyrrolidone with a reactive bifunctional compound, to give a polymer which has a molecular weight at least 2.5 times as great as that of the starting polymer.

Abstract: A novel method for crosslinking a polyolefin comprising reacting a polyolefin, which is a low density polyethylene having a density less than 0.93 and melt index of 0.1-0.5 g/10 min. or a polyolefin mixture containing a low density polyethylene having a density less than 0.93 as major component, with an organic silane and a free radical generating compound to form a silane-grafted polyolefin, then mixing silane-grafted polyolefin with a silanol condensation catalyst, and heating them. According to this method, the crosslinking takes place concurrently with forming by extrusion, and a shaped article having a high degree of crosslinking with smooth surface is obtained. The method according to this invention is especially suited for covering electrical wires with polyolefin.

Abstract: An adhesive composition comprising a 2-cyanoacrylate and at least one member selected from the group consisting of substituted or unsubstituted aliphatic carboxylic acids having three or more carboxyl groups, anhydrides thereof, partial esters thereof, aromatic polycarboxylic acids having three or more carboxyl groups and anhydrides thereof. This composition has a high impact strength, is suitable for bonding metallic substrates to one another and is also excellent in resistance to heat, weather, and water.

Abstract: In the use of certain metal salts of the hemi-perester of maleic acid as catalysts for the polymerization and curing of ethylenically unsaturated monomers and of methyl methacrylate-containing syrups the addition of an activator such as sodium bisulfite provides a substantial reduction in the curing time. The process is relatively insensitive to the amount of filler used. The salts of maleic hemi-peresters, in combination with the activators, are also useful for polymerizing ethylenically unsaturated monomers.