Abstract: New dichroic dyes having a composition with slave materials. The dyes may be used for a dichroic polymer network, a dichroic liquid crystalline polymer film (LCP film) or a dichroic liquid crystalline polymer gel, which for instance find application as electro-optical or optical devices.

Abstract: Disclosed herein are ester-terminated polyimide gellant compounds end-caped with isosorbide and UV curable ink compositions containing them.

Abstract: A process for producing resin particles includes a step in which a polymerizable mixture including a polymerizable monomer including at least one of a styrene-based monomer and a (meth)acrylic-based monomer, and a polymerization initiator is absorbed into seed particles in an aqueous medium, without using a dispersant, in the presence of an anionic surfactant not having a polyoxyethylene chain but having an alkyl group; and a step in which the polymerizable monomer is polymerized in an aqueous medium, without using a dispersant, in the presence of an anionic surfactant having a polyoxyethylene chain to thereby obtain resin particles. The resin particles include a resin derived from a polymerizable monomer including at least one of a styrene-based monomer and a (meth)acrylic-based monomer. The proportion by number of particles having a particle diameter in the range of from 80 to 120% of the volume-average particle diameter is 85% or more.

Abstract: Single ion conductors comprising polymer electrolytes prepared by grafting a salt compound onto a comb-branch polymer or dendrimer are disclosed having superior properties.

Abstract: Fluoroelastomer gum or crumb is isolated from fluoroelastomer dispersions by the addition of a water-soluble polymeric coagulating agent to the dispersion. This coagulating agent comprises either a homopolymer of ethylene oxide (CH2CH2O—) or a copolymer of ethylene oxide. Specific examples of such copolymers include, but are not limited to ethylene oxide-propylene oxide copolymers and ethylene oxide-butylene oxide copolymers. The viscosity average molecular weight (Mv), determined by rheology, of the coagulant polymer must be at least 500,000 and preferably greater than 2,000,000.

Abstract: The invention is a combination of a Methyl Methacrylate liquid monomer and an acrylic powdered polymer that when mixed together will form an extremely strong chemical bond between two plastic substrates by melting into the plastic and filling the space between the substrates. A bond stronger than previously achievable is accomplished by two factors: (1) Substantial use of the liquid as a primer before the application of the mixture in order to prepare the surface for welding. (2) Controlling the temperature of the liquid and the powder, via refrigeration, before mixing. This allows workability of the product without the need for additives that dilute the strength of the mixture. The elimination of the additives also allows for a more pure weld that can be polished to a crystal clear surface for an esthetically pleasing joint.

Abstract: The present invention is a novel block copolymer containing a controlled distribution copolymer block of a conjugated diene and a mono alkenyl arene, where the controlled distribution copolymer block has terminal regions that are rich in conjugated diene units and a center region that is rich in mono alkenyl arene units. Also disclosed is a method for manufacture of the block copolymer.

Abstract: The present invention is a novel block copolymer containing a controlled distribution copolymer block of a conjugated diene and a mono alkenyl arene, where the controlled distribution copolymer block has terminal regions that are rich in conjugated diene units and a center region that is rich in mono alkenyl arene units. Also disclosed is a method for manufacture of the block copolymer.

Abstract: A novel solvent-free, hot melt adhesive composition suitable for bonding a polar leather layer to a non-polar substrate is claimed. The composition comprises a block copolymer having at least one mono alkenyl arene polymer block and at least one controlled distribution copolymer block of at least one conjugated diene and at least one mono alkenyl arene, a hydrogenated tackifying resin, a resin compatible with the mono alkenyl arene blocks, optionally a functionalized poly(alkylene) resin, and stabilizers and/or auxiliaries. A process for bonding a polar leather layer to a non-polar substrate by application of the novel solvent-free, hot melt adhesive composition is also provided.

Abstract: The present invention is a novel block copolymer containing a controlled distribution copolymer block of a conjugated diene and a mono alkenyl arene, where the controlled distribution copolymer block has terminal regions that are rich in conjugated diene units and a center region that is rich in mono alkenyl arene units. Also disclosed is a method for manufacture of the block copolymer.

Abstract: The present invention is a novel block copolymer containing a controlled distribution copolymer block of a conjugated diene and a mono alkenyl arene, where the controlled distribution copolymer block has terminal regions that are rich in conjugated diene units and a center region that is rich in mono alkenyl arene units. Also disclosed is a method for manufacture of the block copolymer.

Abstract: Macromolecules in the shape of three-dimensional kites, barbells, and other shapes are disclosed. The shaped macromolecules are prepared the reaction of one or more dendritic polymers and a linear polymer. The kite-shaped macromolecules are dendritic polymers attached at either their focal points or at an outer to a long carbon chain group. The barbell macromolecules have dendritic polymers at either end of the molecule, which polymers are connected together through the focal points of each by a suitable connecting substituent such as a linear polymer. The shaped macromolecules are used in specialty medical and technological applications including such as drug delivery agents, imaging materials, molecular devices, thin film devices, surface modifiers, transport agents, compatibilizers, rheology control agents, molecular ball bearings, molecular dipoles, non-linear optical materials, medical imaging agents, membrane and cell modifiers, complexing agents, adhesives, interface strengthening agents, and the like.

Abstract: The present invention is a novel block copolymer containing a controlled distribution copolymer block of a conjugated diene and a mono alkenyl arene, where the controlled distribution copolymer block has terminal regions that are rich in conjugated diene units and a center region that is rich in mono alkenyl arene units. Also disclosed is a method for manufacture of the block copolymer.

Abstract: The present invention relates to a photopolymerizable composition, which comprises: (a) a block copolymer component comprising an unhydrogenated styrene diene block copolymer and a hydrogenated controlled distribution styrene diene block copolymer (b) one or more photopolymerizable ethylenically unsaturated low molecular weight compounds, (c) one or more polymerization initiators, and optionally (d) from 0 to 40% by weight, based on the total photopolymerizable compositions, of one or more auxiliaries. The invention also includes flexographic printing plates derived from said photopolymerizable compositions, and flexographic printing relief forms prepared from said plates.

Abstract: The present invention provides a cyanoacrylate adhesive composition having high shear bond strength, peeling bond strength, tensile strength and impact bond strength and superior wear characteristics particularly in toy applications where hostile play environments demand hot-cold cycle resistance. The cyanoacrylate adhesive composition contains (a) up to 20% by weight of a cyanoacrylate monomer, (b) a styrene-based elastomeric block copolymer, and (c) a specific solvent which is selected to effect the solution of both components. The invention is also directed to a method of applying the instant adhesives to substrate surfaces.

Abstract: Single ion conductors comprising polymer electrolytes prepared by grafting a salt compound onto a comb-branch polymer or dendrimer are disclosed having superior properties.

Abstract: The invention provides a flocculant which in sludge dewatering gives flocs having an excellent balance among flocculating strength, filtration rate and moisture content, and a method of sludge dewatering with the flocculant. Namely, the flocculant is a polymeric flocculent which contains a copolymer having alkoxyalkyl units or a poly(alkylene oxide) unit and further having water-soluble monomer units; and the method of sludge dewatering includes adding the polymeric flocculant to a sludge after or without adding an inorganic flocculent or an organic cationic compound thereto and then dewatering the sludge.

Abstract: Improved single ply, water proof roof coverings having an extruded pressure sensitive rubber-based adhesive backing for attachment to a substrate such as the roof of a building or a transport vehicle, the adhesive comprising a thermoplastic rubber containing at least 25% butyl rubber in combination with polyisobutylene and low molecular weight polybutene.

Abstract: Block copolymers having a polyisobutylene segment and a polycycloaliphatic diene polymer segment are presented. Star block copolymers with 2 to 16 block copolymer arms, wherein each of the arms has a polyisobutylene segment and a polycycloaliphatic diene polymer segment, are presented. The star block copolymers are synthesized via the “core first” method.

Abstract: There is provided a process for producing polymer rubber, which comprises the step of polymerizing a conjugated diene monomer or a combination of a conjugated diene monomer with an aromatic vinyl monomer in the presence of (1) an organolithium compound, (2) a solvent, (3) tetrahydrofuran in an amount of 0.0106 to 0.1060% by weight, and (4) ethylene glycol diethyl ether in an amount of 0.02 to 0.30% by weight, wherein the polymer rubber satisfies the conditions of (a) a vinyl group content in the polymer rubber is not less than 60% by weight, and (b) a Q value (Mw/Mn) of the polymer rubber is not more than 1.35.

Abstract: The present invention relates to multiblock interpolymers having the following symmetric structures and processes for their preparation: Y-X-Y, wherein Y represents a block of a random copolymer of conjugated diene and monovinyl aromatic monomer; and X represents a block of butadiene homopolymer, a block of isoprene homopolymer, or a block of butadiene/isoprene copolymer, and processes for the preparation thereof. The present multiblock interpolymers have in the same molecule both a rubber block of random copolymer of conjugated diene and monovinyl aromatic monomer and a rubber block selected from blocks of butadiene homopolymer, isoprene homopolymer and butadiene/isoprene copolymers, and hence possess excellent properties of the both two kinds of rubbers, and can be used widely as integrated rubber materials with excellent property balance, the present processes can simply prepare the above integrated rubber material in situ in a single reactor.

Abstract: The present invention relates to a method of acrylonitrile-butadiene-styrene (ABS) rubber latex, and the acrylonitrile-butadiene-styrene (ABS) latex is prepared by graft-polymerizing butadiene rubber with the monomers of acrlylonitrile and styrene through emulsion-polymerization, so that the ABS rubber latex of the present invention has high solid content. The method of ABS rubber latex of the present invention comprises the step of emulsion-polymerizing i) polybutadiene rubber latex; ii) aromatic vinyl compound; and iii) vinyl cyanide with the addition of a reactive emulsifier. According to the method of the present invention, the ABS rubber latex has high solid content due to a decrease in the amount of coagulated materials and film, which formed on the rubber latex during polymerization, and an increase in the production volume.

Abstract: Provided is a continuous vapor-phase polymerization method for producing polyolefins. In the method, polymer agglomerates and aggregates are prevented from being formed, and polymer deposition on the wall of reactors and around stirring blades is prevented. The method enables continuous and stable production of high-quality polyolefins, with no pipe line clogging. The method is characterized by a specific supply mode of feeding a catalyst activity retardant such as alcohol into polymerization reactors. Specifically, the retardant is fed into the vapor phase in a polymerization reactor and into the powder phase therein through its side wall. Preferably, the retardant is fed into the powder phase through a plurality of sites of the side wall of the reactor.

Abstract: Inherently tacky, pressure-sensitive adhesive compositions useful in marking film applications are provided. The compositions comprise polymer particles prepared by emulsion polymerization of at least one monomer mixture. The monomer mixture comprises at least one alkyl acrylate, the alkyl group of which has from about 4 to 12 carbon atoms, preferably in an amount of from about 73% to 90% by weight, at least one unsaturated carboxylic acid containing from about 3 to 5 carbon atoms, preferably in an amount of from about 2% to 12% by weight, and at least one hard monomer, preferably present in an amount of from about 5% to 15% by weight. The particles have a mean diameter of about 300 nm or less, as determined by laser light scattering. Preferably the hard monomer comprises a styrenic monomer, more preferably both a styrenic monomer and an alkyl methacrylate. In some embodiments, the compositions are prepared by sequential polymerization of the first and second monomer charges.

Abstract: The molecular weight of a graft copolymer is reduced by carrying out the following steps in a non-oxidizing atmosphere: (1) treating a propylene polymer material with an organic compound that is a free radical polymerization initiator, (2) treating the propylene polymer material with about 2 to about 240 parts per hundred parts of the propylene polymer material, of at least one vinyl-substituted grafting monomer in the presence of about 0.5% to about 5% of a polymerizable chain transfer agent that is a derivative of allyl alcohol, and (3) removing any unreacted monomer, decomposing any unreacted initiator, and deactivating any residual free radicals in the material.

Abstract: A curable composition includes a functionalized poly(arylene ether); an alkenyl aromatic monomer; an acryloyl monomer; and a polymeric additive having a glass transition temperature less than or equal to 100° C. and a Young's modulus less than or equal to 1000 megapascals at 25° C. The polymeric additive is soluble in the combined functionalized poly(arylene ether), alkenyl aromatic monomer, and acryloyl monomer at a temperature less than or equal to 50° C. The composition exhibits low shrinkage on curing and improved surface smoothness. It is useful, for example, in the manufacture of automotive body panels.

Abstract: The present invention relates to star-block interpolymers having the following structure (X-Y)n-C, wherein X represents a random copolymer block derived from conjugated diene and monovinyl aromatic monomer; Y represents a polyconjugated diene block; C represents a residue derived from a multifunctional lithium based initiator; and n represents the functionality of the initiator and has a value of not less than 3; and preparation of the same. The star-block interpolymers according to the present invention have in the same molecule both a random copolymer block derived from conjugated diene and monovinyl aromatic monomer and a rubber block selected from the group consisting of a homopolymer block derived from conjugated diene, a tapered copolymer block derived from conjugated dienes, a random copolymer block derived from conjugated dienes and combinations thereof, and hence possess excellent properties of the both kinds of rubbers, and can be used widely as elastomeric materials.

Abstract: A process is disclosed for improving the environmental stress crack resistance and other desirable properties of impact-resistant, elastomer-modified monovinylaromatic compounds, said process utilizing a combination of polymerization initiators, including perketals and peroxycarbonates.

Abstract: A process for producing an isobutylene block copolymer, which comprises performing cationic polymerization of a monomer component containing isobutylene as a major monomer and a monomer component whose major monomer is not isobutylene in the presence of an initiator, wherein the polymerization is carried out in a mixed solvent containing a monohalogenated hydrocarbon solvent and a non-halogenated hydrocarbon solvent the monohalogenated hydrocarbon solvent containing a primary monohalogenated hydrocarbon having three to eight carbon atoms and/or a secondary monohalogenated hydrocarbon having three to eight carbon atoms, the non-halogenated hydrocarbon solvent containing an aliphatic hydrocarbon and/or an aromatic hydrocarbon.

Abstract: The present invention describes the preparation of copolymers grafted by the so-called “grafting from” method, comprising two steps. In the first step, a polymer of a variable type referred to as poly(M1) is reacted with persistent free radicals of the type diphenyltrialkylsilyloxymethyl to form a reactive polymer poly(M1)F, containing a variable number F of these groups attached to the chain. F represents the average functionality of the reactive polymers and may be predetermined by controlling the ratio of poly(M1) and the free radical generator or TPES. In the second step, poly(M1)F is dissolved in a monomer M2 and then redissociated by heating to temperatures of 110-130° C. to produce the macroradical poly(M1) and the persistent radicals. The macroradical poly(M1) rapidly initiates polymerization whereas the diphenyltrialkylsilyloxymethyl radical stays temporarily on the sideline of the initiation reaction.

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 polydipersity 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 mac

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: Methods for preparing uniformly sized polymer particles comprised of multi-functional monomers such as poly(1,4-butanediol diacrylate) and poly(1,6-hexanediol diacrylate) are disclosed. The particles are of a size, uniformity, and contain physical characteristics that make them ideally suitable for use as spacers in liquid crystal display devices.

Abstract: Herein disclosed are a block copolymer having an isobutylene-based polymer block and a vinylic aromatic hydrocarbon-based polymer block and containing a styrenic unit having a halogenated saturated aliphatic hydrocarbon group on the benzene ring at 0.01 to 2 mol % on a basis of the total structural units and being capable of markedly improving the performance of a synthetic resin when the block copolymer is blended with the synthetic resin; a process for producing the block copolymer; and a resin composition position containing the block copolymer.

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: The present invention provides a block polymer which has functional groups on its both ends, and which comprises hydrophilic/hydrophobic segments. As for the functional groups on its both ends, the block polymer has amino group, carboxyl group or mercapto group on .alpha.-terminal, and hydroxyl group, carboxyl group, aldehyde group or vinyl group on .omega.-terminal. Hydrophilic segment comprises polyethylene oxide, while hydrophobic segment is derived from lactide, lactone or (meth)acrylic acid ester. The block polymer of this invention forms a polymeric micelle which is usable as bio-compatible materials.

Abstract: A reactive monomer for preparing ultraviolet absorbing polymers has formula (I) wherein R.sup.1 is a halogen or C.sub.1 -C.sub.6 straight or branched chain alkoxy group; and R is a --(CH.sub.2).sub.3 O--, --(CH.sub.2).sub.2 O--, --CH(CH.sub.3)CH.sub.2 O--, --CH.sub.2 CH(CH.sub.3)O(--, --(CH.sub.2).sub.3 OCH.sub.2 --, --(CH.sub.2).sub.2 OCH.sub.2 --, --CH(CH.sub.3)CH.sub.2 OCH.sub.2 --, or --CH.sub.2 CH(CH.sub.3)OCH.sub.2 --group. The compound can be used to produce ultraviolet absorbing polymers, such as those used for ocular devices including contact and intraocular lenses.

Abstract: There is a need for polymers which offer increased heat resistance, ultraviolet light resistance, and low fogging characteristics for utilization in automotive interiors. It is particularly critical for polymers which are utilized in making skin compounds for automotive instrument and door panels to display excellent heat resistance, ultraviolet light resistance, and low fogging characteristics.

Abstract: A process for the polymerization of dienes which comprises anionically polymerizing dienes in the presence of an anionic polymerization initiator and a microstructure control agent is improved by adding the control agent to the polymerization mixture in two or more doses to closely control the vinyl content of the polymer produced.

Abstract: There is a need for polymers which offer increased heat resistance, ultraviolet light resistance, and low fogging characteristics for utilization in automotive interiors. It is particularly critical for polymers which are utilized in making skin compounds for automotive instrument and door panels to display excellent heat resistance, ultraviolet light resistance, and low fogging characteristics.

Abstract: A reactive monomer for preparing ultraviolet absorbing polymers has formula (I) wherein R.sup.1 is a halogen or C.sub.1 -C.sub.6 straight or branched chain alkoxy group; and R.sup.2 is a --(CH.sub.2).sub.3 O--, --(CH.sub.2).sub.2 O--, --CH(CH.sub.3)CH.sub.2 O--, --CH.sub.2 CH(CH.sub.3)O--, --(CH.sub.2).sub.3 OCH.sub.2 --, --(CH.sub.2).sub.2 OCH.sub.2 --, --CH(CH.sub.3)CH.sub.2 OCH.sub.2 --, or --CH.sub.2 CH(CH.sub.3)OCH.sub.2 -- group. The compound can be used to produce ultraviolet absorbing polymers, such as those used for ocular devices including contact and intraocular lenses.

Abstract: A method for modifying polyolefins by grafting with a carboxylic acid, carboxylic acid anhydride or other functionalized monomer in the presence of two additional comonomers, one being an aliphatic diolefin and the other an aromatic vinyl or (meth)acrylate monomer.

Abstract: Polymer particles which are substantially spherical and have protrusions on the surface thereof, with such a particle size distribution that the volume mean diameter dv thereof is 1.ltoreq.dv.ltoreq.15 (.mu.m), and the ratio of the volume mean diameter dv to the number mean diameter dn thereof, that is, dv/dn, is 1.ltoreq.dv/dn.ltoreq.1.2, are prepared, and used as a component for a toner for use in electrophotography.

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 continuous process for producing a propylene-ethylene block copolymer having well-balanced properties of impact strength, stiffness, processability, etc. using a highly active catalyst, with a superior productivity is provided,which process comprisesa first polymerization step (I), carried out using a catalyst system consisting of [A] a solid catalyst component containing Ti, Mg, halogen and a polyvalent carboxylic acid ester as indispensable components, [B] an organoaluminum compound catalyst component and [C] an electron-donating compound,using two or more continuous polymerization vessels, andfeeding monomer(s) of ethylene/(ethylene+propylene) of 0 to 5% by weight, to carry out polymerization composed mainly of propylene, so as to give 60 to 95% of the total polymerized quantity;a continuous addition of a glycol compound (D) expressed by the formulaR.sup.1 --(OC.sub.m H.sub.2m).sub.n --OR.sup.2wherein m is an integer of 2 or more, n is an integer of 3 or more, R.sup.1 and R.sup.

Abstract: Particulates of a superabsorbent polymer, e.g., an acrylic polymer such as polyacrylic acid, well suited for a variety of hygienic applications, are prepared by (i) suspending an aqueous solution of a water-soluble monomer charge I in a hydrocarbon medium by means of a polymerizable surfactant having the general formula:R.sub.1 --O--(CH.sub.2 --CH.sub.2 --O).sub.n --R.sub.2wherein R.sub.1 is a hydrocarbon having at least 9 carbon atoms, R.sub.2 is an acryloyl, methacryloyl or maleoyl radical, and the degree of condensation n in respect of the ethylene oxide ranges from 30 to 70, (ii) polymerizing the suspension thus formed, producing a suspension of polymer gel particles and converting the surfactant to effectively remove same from the medium of polymerization, (iii) next absorbing a second monomer charge II into such gel particles, and (iv) polymerizing in the gel particles the second monomer charge II.

Abstract: Particulates of a superabsorbent partially, neutralized acrylic polymer, e.g., polyacrylic acid, having a mean particle size ranging from 100 to 500 .mu.m, essentially monodisperse and essentially devoid of fines having a particle size of less than 100 .mu.m, having a nonuniformly surfaced spheroidal particle morphology and well suited for a variety of hygienic applications, are prepared by (i) polymerizing a suspension of an acrylic monomer charge I in an organic medium and producing a suspension of acrylic polymer gel particles, such acrylic monomer charge I having a degree of neutralization greater than that desired in the final superabsorbent polymer, (ii) next absorbing a second acrylic monomer charge II into the gel particles, such acrylic monomer charge II having a degree of neutralization less than that desired in the final superabsorbent polymer, and (iii) polymerizing in the gel particles the second acrylic monomer charge II.

Abstract: A thermoplastic resin composition comprising 10 to 60 parts of a graft copolymer (A) and 90 to 40 parts of a rigid copolymer (B), both defined below:(A) The graft copolymer obtained by emulsion graft polymerizing 60 to 20 parts of a specific monomer mixture in the presence of 40 to 80 parts (as solids) of an ethylene-propylene-non-conjugated diene copolymer-containing cross-linked latex containing 0.1 to 20 parts of a modified low molecular weight .alpha.-olefin copolymer in 100 parts of an ethylene-propylene-non-conjugated diene copolymer.(B) The rigid copolymer containing 60 to 76% of an aromatic vinyl type monomer, 40 to 24% of a vinyl cyanide type monomer, and 0 to 30% of a monomer copolymerizable with these monomers.In the production of the graft copolymer (A), a redox type initiator and a monomer mixture are added to the polymerization system continuously over a period of one hour.

Abstract: Process for preparing a graft copolymer having a high graft copolymer fraction which comprises subjecting a monomer to a polymerization initiation condition resulting from the reaction of a halogen-containing polymer with a combination of a reducing agent and a phase transfer catalyst such as an onium compound thereby to polymerize said monomer.

Abstract: The present invention is directed to a process for the preparation of a finely divided vinyl chloride graft copolymer and to the use of this product as a viscosity-reducing agent for plastisols.