Abstract: The present invention is directed to a process of atom (or group) transfer radical polymerization for the synthesis of novel homopolymer or a block or graft copolymer, optionally containing at least one polar group, with well defined molecular architecture and narrow polydispersity index, in the presence of an initiating system comprising (i) an initiator having a radically transferrable atom or group, (ii) a transition metal compound, and (iii) a ligand; the present invention is also directed to the synthesis of a macromolecule having at least two halogen groups which can be used as a macroinitiator component (i) to subsequently form a block or graft copolymer by an atom or group transfer radical polymerization process; the present invention is also directed to a process of atom or group transfer radical polymerization for the synthesis of a branched or hyperbranched polymer; in addition, the present invention is directed to a process of atom or group transfer radical polymerization for the synthesis of a ma

Abstract: A graft copolymer comprising a backbone of a propylene polymer material having a vinyl monomer graft polymerized thereto is produced by (1) treating a propylene polymer material with a free radical polymerization initiator, (2) treating the propylene polymer material with at least one grafting monomer capable of being polymerized by free radicals, in the presence of a polymerization rate modifier, and (3) removing any unreacted grafting monomer from the graft copolymerized propylene polymer material, decomposing any unreacted initiator, and deactivating any residual free radicals in the material. Use of the polymerization rate modifier increases the polymerization induction time on the polymer surface, consequently facilitating monomer diffusion into the interior of the polymer particles so that surface polymerization of the monomer is inhibited.

Abstract: A crosslinkable composition of a polymeric thermoplastic and/or elastomeric material which is susceptible to scorching when processed at elevated temperatures, prior to crosslinking, in the presence of a free radical initiator, is protected against such scorching by the incorporation therein of a mixture of at least one hydroquinone compound and a sulfur accelerator. This mixture may also contain at least one monomeric allylic, methacrylic, acrylic or diene type coagent. The mixture exhibits a synergistic effect resulting in improved scorch protection for peroxide cured systems when compared with the protection afforded by the components singly.

Abstract: Cationically curable adhesives and sealants with increased viscosities and improved rheological control and good storage stability are prepared using a cationically curable monomer and a thickening polymer which is the alkylation reaction product of poly(4-hydroxystyrene) or poly(2-hydroxystyrene) with a compound RX where R is allyl, methallyl, crotyl or prenyl and X is Cl, Br or I. The cationically curable monomer suitably includes at least one alkenyloxystyrene monomer. Such thickened adhesives are useful as edge sealants for flat panel display devices. A-stage curing of the adhesive with UV irradiation allows for near ambient temperature fixturing of the device assemblies and B-stage thermal curing of the adhesive can be conducted at much lower temperatures than are needed for glass frit sealants. The B-stage cured products have thermal resistance, outgassing and substrate adhesion properties adequate for flat panel display devices.

Abstract: A curable resin composition comprising:(1) a polymerizable vinyl monomer having a structure of the formula (A):Z--R--(R.sub.2 O).sub.p --R.sub.1 (A)wherein Z is a (meth)acryloyl group, R.sub.1 is a phenyl group or a phenyl group having a C.sub.1-3 alkyl group, R.sub.2 is --C.sub.2 H.sub.4 --, --C.sub.3 H.sub.6 --, --CH.sub.2 CH(CH.sub.3)--, --C.sub.4 H.sub.8 -- or --C.sub.6 H.sub.12 --, and p is an integer of from 1 to 10 and wherein R is a direct bond,(2) a polymerizable vinyl monomer having a structure of the formula (B): ##STR1## wherein Z and R.sub.2 are as defined above, R.sub.3 is hydrogen or a C.sub.1-4 alkyl group, and q is an integer of from 0 to 8,(3) a polymerizable vinyl monomer having a structure of the formula (C):Z--O--(R.sub.2 O).sub.p --H (C)wherein Z, R.sub.2 and p are as defined above,(4) an organic peroxide, and(5) a reducing agent.

Abstract: Open cell foamed articles including silane-grafted single-site inititiated polyolefin resins are described. The single-site initiated olefin polymer resin can be a polyethylene, a copolymer of ethylene, a C3-C20 alpha-olefin, or a copolymer of ethylene, a C3-C20 alpha-olefin and a C4-C20 diene. The open cell foamed articles have good cushioning properties and can be non-allergenic.

Abstract: A one-component, thermosetting resin composition curable through a Michael reaction between (a) a component having a plurality of .alpha., .beta.-unsaturated carbonyl groups and (b) a component having a plurality of activated methylene of activated methyne groups is disclosed. The curing reaction is catalyzed with a quaternary ammonium, quaternary phosphonium or tertiary sulfonium salt in the presence of a five-membered cyclic carbonate compound independently added to the composition or covalently attached to either component (a) or component (b).

Abstract: A free radical polymerization process for the preparation of a polymer comprising heating a mixture of a free radical initiator, a stable free radical agent, a metal catalyst, or a metal stable free radical complex catalyst, and at least one polymerizable monomer; cooling said mixture; and optionally isolating said polymer.

Abstract: An isobutylene-based polymer as a polymer of cationically polymerizable monomers principally composed of isobutylene or a combination of isobutylene and a styrene-series monomer, generates a molded article with outstanding properties, the isobutylene-based polymer characteristically satisfying the following provisions;1. the isobutylene-based polymer has a substantially continuos molecular weight distribution on a gel-permeation chromatogram;2. the molecular weight at the highest peak on a gel-permeation chromatogram is within a range of 10,000 to 500,000; and3. the length (a) of the elution time in the lower molecular region of the mountain from the highest peak and the length (b) of the elution time in the higher molecular region of the mountain from the highest peak on a gel-permeation chromatogram, satisfy the provision represented by the formula (b)/(a).gtoreq.1.3.

Abstract: An acrylate composition, especially useful for producing conformal coatings on circuit board assemblies, includes a photoinitiator and an air-curing system, the latter being comprised of a compound having multiple allyloxy groups in its molecule and a transition metal salt catalyst. The composition is highly stable against auto-induced reaction in the absence of oxygen and at room temperature; it contains no active oxygen catalyst and no nonreactive diluent, and is advantageously formulated as a one-part product.

Abstract: Multistage process for the polymerization of one or more olefins of the formula CH.sub.2 .dbd.CHR, in which R is hydrogen or an alkyl, cycloalkyl or aryl group having from 1 to 10 carbon atoms, comprising:(A) a first stage of polymerization, in which a first olefin polymer is prepared in the presence of titanium catalyst or vanadium catalyst;(B) a treatment stage in which the catalyst used previously is deactivated and in which a metallocene compound is supported on the olefin polymer produced in stage (A); and(C) a second stage of polymerization in which one or more olefins are polymerized in the presence of the product obtained from stage (B).

Abstract: Disclosed are a polypropylene composition comprising 95-55 parts by weight of polypropylene (A) and 5-45 parts by weight of an ethylene/1-butene random copolymer (B-1) which contains constituent units derived from 1-butene in an amount of 15 to 25% by mol; and a polypropylene composition comprising 95-55 parts by weight of polypropylene (A) and 5-45 parts by weight of an ethylene/1-octene random copolymer (B-2) which contains constituent units derived from 1-octene in an amount of 8 to 20% by mol. Each of the random copolymers (B-1) and (B-2) has an intrinsic viscosity [.eta.] of 1.5 to 3.5 dl/g as measured in decalin, a glass transition temperature (Tg) of not higher than -50.degree. C., a crystallinity of less than 20% as measured by X-ray diffractometry, a randomness parameter (B value) of 1.0 to 1.4 as measured by .sup.13 C-NMR spectroscopy. With respect to a melting point as measured by a differential scanning calorimeter (DSC) as the main peak, the copolymer (B-1) has a value of not higher than 60.

Abstract: Disclosed are a polypropylene composition comprising 95-55 parts by weight of polypropylene (A) and 5-45 parts by weight of an ethylene/1-butene random copolymer (B-1) which contains constituent units derived from 1-butene in an amount of 15 to 25% by mol; and a polypropylene composition comprising 95-55 parts by weight of polypropylene (A) and 5-45 parts by weight of an ethylene/1-octene random copolymer (B-2) which contains constituent units derived from 1-octene in an amount of 8 to 20% by mol. Each of the random copolymers (B-1) and (B-2) has an intrinsic viscosity [.eta.] of 1.5 to 3.5 dl/g as measured in decalin, a glass transition temperature (Tg) of not higher than -50.degree. C., a crystallinity of less than 20% as measured by X-ray diffractometry, a randomness parameter (B value) of 1.0 to 1.4 as measured by .sup.13 C-NMR spectroscopy. With respect to a melting point as measured by a differential scanning calorimeter (DSC) as the main peak, the copolymer (B-1) has a value of not higher than 60.

Abstract: There are herein disclosed an olefin copolymer which comprises an olefin unit and a diolefin unit and in which a weight-average molecular weight is in the range of 200 to 800,000, the content of the diolefin unit is in the range of 0.002 to 30 mol%, and a ratio TUS/DOU between the total content of unsaturated groups observed in a molecular chain (TUS mol%) and the content of the diolefin unit (DOU mol%) is in the range of 0.001 to 200; an olefin graft copolymer obtained by the graft polymerization of this olefin copolymer and an olefin; a hydrogenated olefin copolymer and olefin graft copolymer thereof; and a process for preparing these copolymers.These olefin copolymers are excellent in molding/working properties and have a good thermal stability, transparency and uniformity. Therefore, they are useful as a high-performance VLDPE, LDPE, L-LDPE and HDPE, and further useful as a novel branched propylene polymer, a thermoplastic elastomer, a compatibilizing agent for other resins, and the like.

Abstract: Multistage process for the polymerization of olefins CH.sub.2 .dbd.CHR, where R is hydrogen or an alkyl, cycloalkyl or aryl radical with 1-10 carbon atoms, comprising two stages of polymerization. In a first stage, in the presence of a titanium or a vanadium catalyst and working in one or more reactors, an olefinic polymer with particular values of porosity is prepared; in a second stage, in the presence of the said porous polymer and a metallocene compound and/or their reaction products, one or more olefins, that are equal to or different from those polymerized in the first stage, are polymerized in one or more reactors.

Abstract: An air curing polymer composition is disclosed which contains acetoacetate functional polymer and an autoxidizable material. The composition cures on exposure to oxygen. One pack stable ambient curing compositions and a method of stabilizing acetoacetate functional groups to prevent hydrolysis are also disclosed.

Abstract: This invention is directed to a fast curing polymer composition which does not require baking or thermosetting to provide a cross-linked coating binder. The composition comprises a polymer which is a homopolymer or copolymer of alpha, beta unsaturated monomers having pendent acetylenic groups which cross-link upon air drying to provide a coating binder.

Abstract: A vulcanizable, fluorine-containing elastomer composition, which comprises a fluorine-containing elastomer containing at least one of iodine and bromine in the molecule, salicylaldo-imino copper complex having the following formula: ##STR1## as a cross-linking agent, and a polyfunctional unsaturated compound as a cross-linking aid can produce vulcanized products having a largely improved modulus of elasticity.

Abstract: A graft copolymer dispersant (binder) having a weight average molecular weight of about 5,000-100,000 wherein: (1) the graft copolymer has a polymeric backbone formed by polymerizing ethylenically unsaturated monomers; (2) the graft copolymer has macromonomer side chains attached to the backbone at a single terminal point that have weight average molecular weights of about 1,000-30,000 and are formed from by polymerizing ethylenically unsaturated monomers in the presence of a cobalt chain transfer agent. The graft copolymer further contains about 2 to 70% by weight, based on the weight of the graft copolymer, of polymerized constituents having a phosphate moiety or phosphoric acid moleties that are polymerized into the backbone, the side chains, or both. The graft copolymer is neutralized with an inorganic base or an amine.

Abstract: An air curing polymer composition is disclosed which contains acetoacetate functional polymer and an autoxidizable material. The composition cures on exposure to oxygen. One pack stable ambient curing compositions and a method of stabilizing acetoacetate functional groups to prevent hydrolysis are also disclosed.

Abstract: Crystalline propylene polymers having P.I. values lower than or equal to 3.7, and having, at an MFR (Melt Flow Rate) ranging from 600 to 1000 g/10 min., an Mw value from 100,000 to 60,000, and at a MFR ranging from 1000 to 2000 g/10 min., an Mz value higher than or equal to 140,000, are obtained by way of polymerization with specific supported catalysts.

Abstract: A new curable compounded halopolymer that exhibits in the cured state good to excellent adhesion to polyamides. These curable halopolymer achieves better adhesion due to a balance of carbon black relative to talc, preferable with the cyclohexyl benzothiazole sulfenamide or related benzothiazole sulfenamide and are highly desirable in making specialty hoses and belts.

Abstract: A catalyst system for the polymerization of alpha-olefins comprising a chromium-containing catalyst and an yttrium-containing catalyst wherein the yttrium-containing catalyst is represented by the formula (Cp.sub.2 YX.sub.x).sub.y .multidot.M.sub.z L.sub.n, wherein Cp is cyclopentadienyl or cyclopentadienyl substituted with an alkyl or alkyl silyl radical, X is a halogen, M is an alkali metal, L is a suitable electron donor ligand, x is 1 or 2, y is 1 or 2, z is 0 or 1, and n is a number corresponding to the value needed to form a stable complex, with the proviso that when y is 2, z and n are 0 is provided. Also disclosed is a polymerization process employing such a catalyst system, and novel olefin polymers. Polymers thus produced exhibit high bulk density and a broad molecular weight distribution.

Abstract: A graft polymer obtainable by grafting a polymer substrate with a compound of formula (I), in which the groups R are the same or different and each is a straight or branched C.sub.1 -C.sub.4 alkyl group; X is an aryl group or a straight or branched C.sub.1 -C.sub.20 alkylene group, optionally containing one or more carbon-carbon double or triple bonds, ether linkages or aryl groups; the aryl groups being unsubstituted or substituted by one or more C.sub.1-4 alkyl groups; n is from 2 to 4; and A is a reactive group, is useful as a biocompatible material in contact lenses, biomedical devices and blood-containing devices. In a preferred embodiment A is a polymerizable group and the graft polymer is produced by radical initiated polymerization of the compound of formula (I) on the substrate which is initiated by a radical-forming group on the substrate.

Abstract: A vulcanizable, fluorine-containing elastomer composition, which comprises a fluorine-containing elastomer copolymerized with chlorotrifluoroethylene, (A) a salicylaldo-imino copper complex having the following chemical formula as a cross-linking agent: ##STR1## (B) at least one of a divalent metal oxide and hydroxide as an acid receptor, and (C) a polyfunctional unsaturated compound as a cross-linking agent have a high vulcanization rate and good physical properties in the normal state of vulcanization product.

Abstract: Depolymerization or molecular weight reduction of polymers and gelled polymers containing internal unsaturation along the polymer backbone is performed in the presence of a molybdenum or tungsten compounds having the structural formula:M(NR.sub.1)(OR.sub.2).sub.2 (CHR.sub.3)wherein M is molybdenum or tungsten;R.sub.1 and R.sub.2 are unsubstituted or halo-substituted alkyl, aryl, aralkyl groups or silicon-containing analogs thereof;R.sub.3 is an alkyl, aryl, aralkyl group of any substituent that results from the initial reaction between the M.dbd.CHR.sub.3 complex and an olefin treating agent.

Abstract: The present invention provides a process for the living polymerization of aromatic, preferably styrenic monomers initiated from a living polyolefin, particularly polyisobutylene, chain end and thereby provides an efficient method for the preparation of block copolymers having polyolefin mid-blocks and styrenic end blocks. Polyisobutylene mid blocks and styrenic end blocks comprising para-methylstyrene, alpha-methylstyrene, indene and the like are preferred.

Abstract: The invention describes a redox initiating system consisting of Cu.sup.II salts, enolizable aldehydes and ketones, and various combinations of coordinating agents for Cu.sup.II, coordinating agents for Cu.sup.I, and a strong amine base that is not oxidized by Cu.sup.II. In particular, Cu.sup.II octanoate/dibenzyl ketone/pyridine/triethylamine/triphenylphosphine systems are effective. In addition to initiating free radical polymerizations and copolymerizations, this initiating system can be applied to the synthesis of functionalized telechelics, polymers with ketone linkages in the backbone, block and graft copolymers consisting of free-radical and step-growth polymer blocks, and crosslinking reactions.

Abstract: A catalyst system for the polymerization of alpha-olefins comprising a chromium-containing catalyst and an yttrium-containing catalyst wherein the yttrium-containing catalyst is represented by the formula (Cp.sub.2 YX.sub.x).sub.y.M.sub.z L.sub.n, wherein Cp is cyclopentadienyl or cyclopentadienyl substituted with alkyl or alkyl silyl radical or radicals, X is a halogen, M is an alkali metal, L is a suitable electron donor ligand, x is 1 or 2, y is 1 or 2, z is 0 or 1, and n is a number corresponding to the value needed to form a stable complex, with the proviso that when y is 2, z and n are 0 is provided. Also disclosed is a polymerization process employing such a catalyst system, and novel olefin polymers. Polymers thus produced exhibit high bulk density and a broad molecular weight distribution.

Abstract: The invention relates to the preparation of a graft copolymer latex of core/shell dispersion particles having improved phase binding between core and shell in a two-stage emulsion polymerization process, hydroperoxide groups being produced at the particle surface of the grafting base prior to grafting by hydrogen peroxide treatment.

Abstract: Shelf stable nonwoven fabrics and films are made from polyolefin compositions which comprise a polyolefin which contains no more than a minor amount of a phenolic antioxidant, a water-sensitive stabilizer, a transition metal organic salt and an oxidizable unsaturated compound.

Abstract: Process for making a polymer with desired groups Y comprising reacting a precursor polymer having carbon- or nitrogen-bound --NH.sub.2 and/or --NH-- groups with at least one compound having a single enolic carbonyl group and at least one group Y. Also the polymer itself and a composition containing it.

Abstract: Propylene-ethylene copolymers are obtained by two-stage polymerization from the gaseous phase in an agitated fixed bed by means of a Ziegler-Natta catalyst system that contains in addition to a titanium-containing solid component also an aluminum compound as co-catalyst, wherein as Ziegler-Natta catalyst system a system is used which, following the reaction of the titanium-containing solid component with the co-catalyst, is deactivated by reaction with carbon dioxide. The copolymers are used for producing fibers, films and moldings.

Abstract: By using salicylaldoimino copper complex having the following formula as a cross-linking agent for a fluorine-containing elastomer containing at least one of iodine and bromine in the molecule, a vulcanization product with an improved heat resistance can be obtained and generation of harmful substances such as methyl iodine, methyl bromine, etc.

Abstract: There are disclosed a process for producing a vinyl ester polymer having a high degree of polymerization at a high efficiency, which process comprises subjecting a vinyl ester monomer to seed polymerization by the use of a vinyl ester polymer emulsion as a seed emulsion under the conditions in which the charge of a water-soluble initiator per unit volume (1 liter) of reactant liquid charge is 1.times.10.sup.-8 to 2.times.10.sup.-4 mol, and the charge of the water-soluble initiator per one particle of the vinyl ester polymer particles in the seed emulsion is 1.times.10.sup.-28 to 1.times.10.sup.-20 mol, and a process for producing a vinyl alcohol polymer at a high efficiency from the vinyl ester polymer thus obtained.According to these processes of the present invention, both a vinyl ester polymer and vinyl alcohol polymer each having a higher degree of polymerization can be produced with ease on an industrial scale.

Abstract: Tough, puncture- and tear-resistant films having a high degree of flexibility and softness are provided. The monolayer and multilayer films of the invention are obtained using copolymers of propylene with 8 to 40 weight percent ethylene produced by gas phase polymerization of the monomers in dual reactors. The films will have a 1% secant modulus from 5,000 psi to 70,000 psi. Melting points of these films are higher than that of low density polyethylene and, most generally, in the range 125.degree. C. to 160.degree. C.

Abstract: A process for preparing an impact resistant resin, which comprises a step of graft copolymerizing a monomer mixture comprising an aromatic vinyl monomer and a monomer copolymerizable therewith, to a butadiene rubber-like polymeric latex in the presence of a redox polymerization initiator; a step of coagulating the resulting graft copolymer latex by mixing an antioxidant thereto and adding an alkaline earth metal salt thereto; and a step of washing the coagulated product by a washing water having the pH adjusted to a level of at most 7.

Abstract: A process for producing an emulsion graft copolymer, which comprises grafting a vinyl aromatic monomer and a comonomer onto a rubber latex in the presence of an iron (II) redox system as polymerization catalyst and coagulating the graft copolymer latex with an alkaline earth metal compound, characterized in that the pH of the coagulated slurry is adjusted to a value ranging from 8 to 12a) by addition of an alkali metal hydroxide to the obtained slurry after coagulation,b) by addition of an alkali metal hydroxide to the graft copolymer latex before coagulation, orc) by coagulating the graft copolymer latex with an alkaline earth metal hydroxide,with the proviso that the solidified product of the slurry obtained according to a), b) or c) is not washed with acidified water in a subsequent processing step.Graft copolymers are used e.g. for reinforcement of natural rubber, modification of rubber-based adhesives, in fibres, or in films.

Abstract: This invention relates to vinyl monomer compositions having accelerated surface cure characteristics. These compositions are prepared from a vinyl monomer or monomer mixtures such as blend of isobornyl methacrylate and hydroxypropyl methacrylate, a bulk phase polymerization catalyst system, a polyvalent metal oxidative surface phase catalyst, and a diolefin rubber dispersed in the vinyl monomer as a surface cure accelerator. These compositions are useful as sealers, healers and for polymer concrete.

Abstract: A crosslinkable resin composition containing:(A) from 10% to 90% by weight of a thermoplastic resin component,(B) from 90% to 10% by weight of a curable resin component, comprising, expressed by reference to the curable resin (100%),(i) 50% to 95% of a (meth)acryloyl derivative, and(ii) 50% to 5% of a (meth)allyloxy derivative, and(C) from 0% to 30% by weight of a plasticiser for the thermoplastic resin component, is disclosed.Also a new crosslinked resin layer and a process for the manufacture of the new crosslinked resin layer on a substrate are described.The crosslinked resin layer herein exhibits a desirable balance between flexibility, resistance to stain and resistance to scuff properties, in combination with outstanding mechanical and chemical properties.The crosslinkable resin composition is particularly suitable for coating application of various substrates such as flooring materials, wall covering materials, coils, wires, and various shaped articles e.g. cars, containers and metallic profiles.

Abstract: A process for the polymerization of olefins in the presence of hydrogen comprising contacting the olefin, a cyclopentadienyl compound and a catalyst comprising a transition metal compound at polymerization conditions.

Abstract: A high volume amine-aldehyde initiator composition for two part acrylic adhesives is disclosed comprising a mixture of the amine-aldehyde condensate and a diluent comprising an epoxy ether, e.g. the diglycidyl ether of bisphenol A. The initiator compositions are designed for use in dispensing two part acrylic adhesives from self-proportioning twin pack cartridge dispensers at adhesive:initiator ratios of 20:1 or less, e.g. 10:1.

Abstract: A process for grafting halogenated butyl rubbers with polymers based on conjugated diolefin monomers is provided which comprises mixing a first solution of halogenated butyl rubber with a second solution of a living alkali metal terminated polymer based on conjugated diolefin monomers and having a number average molecular weight of at least 40,000 at a temperature of from about -10.degree. C. to about 80.degree. C. for a period of time of from about 30 minutes to about 24 hours whereby the graft copolymer is formed. Rubber compositions comprising the halogenated butyl rubber graft copolymers upon vulcanization exhibit improved abrasion resistance and wet skid resistance while a desirable balance of other physical properties is maintained.

Abstract: Polypropylene impact copolymer compositions demonstrate not only good low temperature properties, including impact strength, but also resistance to stress whitening when the numerical ratio of the intrinsic viscosity of the copolymer phase to the intrinsic viscosity of the homopolymer phase is near unity and ethylene contents of the copolymer phase are in the range of 38% to 60% by weight. The impact copolymer compositions are useful in the production of molded and extruded articles, shaped containers, and films having good clarity.

Abstract: There is provided a process for producing a styrenic graft copolymer which comprises coplymerizing a styrenic monomer and a styrenic monomer having a hydrocarbon radical with an unsaturated bond in the presence of a catalyst comprising as primary ingredient (A) a transition metal compound and (B) a contact product of an organoaluminum compound and a condensation agent or (C) a compound which produces an ionic complex by reacting with the above-mentioned transition metal compound and subsequently graft polymerizing an ethylenically unsaturated monomer onto the resultant styrenic copolymer.The above-described styrenic graft copolymer is greatly improved in terms of compatibility, adhesivity, coatability and wettability while preserving heat resistance and chemical resistance thereof, and thus effective as a variety of constructional materials and compatibilizing agents.

Abstract: Graft copolymers obtained byA) emulsion polymerization of from 5 to 35% by weight of a monomer mixture ofa.sub.1) 60-80% by weight of one or more vinylaromatic monomers,a.sub.2) 20-40% by weight of one or more ethylenically unsaturated nitriles,B) subsequent emulsion polymerization, in the presence of the emulsion polymer obtained in stage A), of 20-45% by weight of a monomer mixture ofb.sub.1) 50-75% by weight of one or more vinylaromatic monomers,b.sub.2) 25-50% by weight of one or more C.sub.1 -C.sub.18 -alkyl acrylates,C) subsequent emulsion polymerization, in the presence of the emulsion polymer obtained in stage B), of 5-35% by weight of a monomer mixture ofc.sub.1) 60-80% by weight of one or more vinylaromatic monomers,c.sub.2) 20-40% by weight of one or more ethylenically unsaturated nitriles,D) subsequent emulsion polymerization, in the presence of the emulsion polymer obtained in stage C), of 15-45% by weight of a monomer mixture ofd.sub.1) 80-99.9% by weight of one or more C.sub.1 -C.sub.

Abstract: A heterofunctional macromer represented by the formula: ##STR1## in which R.sub.1 is H or C.sub.1 -C.sub.4 alkyl; R.sub.2 is a (poly) lactone or (poly) ether chain; X.sub.1 is --COO--, --COOCH.sub.2 CH.sub.2 OCO--, --CONHCOO--, --COOCH.sub.2 CH.sub.2 NH--COO-- or ##STR2## X.sub.2 is --O--, --COO-- or --OCO--NH--R.sub.3 --NHCOO-- group; R.sub.3 is C.sub.1 -C.sub.6 alkylene, aromatic or alicyclic group; A is --CH.sub.2 --, --C(CH.sub.3).sub.2 -- or ##STR3## and reactive polymers derived from said macromer.

Abstract: According to the present invention, molded articles can be provided in which a melting point attributed to a syndiotactic polypropylene and measured at a temperature rise rate of 10.degree. C./minute by differential scanning thermal analysis is indicated by a substantially single peak, the aforesaid molded articles being obtained by heating, melting and molding a substantially syndiotactic homopolymer of propylene, a substantially syndiotactic copolymer of propylene and a small amount of another olefin, or a mixture of these polymers and a small amount of a substantially isotactic polypropylene, and then subjecting the molded products to a heat treatment. Furthermore, a method for preparing the above-mentioned molded articles is also provided. The molded articles have high stiffness and impact resistance.

Abstract: A graft copolymer resin composition having improved impact resistance, particularly at low temperature, obtained by emulsion-polymerizing an aromatic vinyl monomer and a vinyl cyanide monomer, optionally together with an ethylenically unsaturated monomer copolymerizable therein under specific conditions by the action of a polymerization initiator in the presence of a latex of a conjugated diene polymer under specific conditions.

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.