Abstract: A rubber modified styrenic resin composition which can be obtained by dispersing rubber-like polymer particles in a homopolymer or a copolymer of a styrenic monomer. The rubber modified styrenic resin composition has:(a) a volume-average particle size of the rubber-like polymer particles is in the range of from 0.2 to 0.8 .mu.m,(b) a particle size distribution curve on the basis of the volume of the rubber-like polymer particles has one peak,(c) a ratio of a 5% value to a 95% value of the cumulative distribution of the particle size on the basis of the volume of the rubber-like polymer particles is in the range of from 3 to 45.

Abstract: The present invention relates to ABS (Acrylonitrile-Butadiene-Styrene) resins having excellent impact resistance, low-gloss properties and superior heat resistance, and to a process for preparing them. In particular, between 5 wt % and 20 wt % butadiene rubber having double bonds is dissolved in between 30 wt % and 70 wt % graft-copolymerizing aromatic vinyl monomer and between 10 wt % and 50 wt % cyanized vinyl monomer. Polymerization controller and radical initiator are added to the above, and the mixture polymerized in a first step of bulk polymerization at a temperature of 80.degree.-120.degree. C. while stirring until polymerization proceeds to between 20 and 50% of completion. Between 40% and 70% .alpha.-methyl styrene monomer, between 10 wt % and 40 wt % unsaturated nitrile and between 5 wt % and 15 wt % butadiene rubber are then added to the polymerized mixture and the resulting mixture stirred for 30-60 minutes in a second step of bulk polymerization.

Abstract: The present invention includes star polymers which can be used as viscosity index improvers in oil compositions formulated for high performance engines. The star polymers have triblock copolymer arms of hydrogenated polyisoprene-polybutadiene-polyisoprene, which provide excellent low temperature performance in lubricating oils, and can be used in the presence of low pour point depressant concentrations.

Abstract: The present invention includes star polymers which can be used as viscosity index improvers in oil compositions formulated for high performance engines. The star polymers have triblock copolymer arms of hydrogenated polyisoprene and polystyrene wherein the polystyrene is placed near the core of the star polymer to provide excellent low temperature performance and finishability as a polymer crumb.

Abstract: Blends of ABS polymers with different substrate particle sizes are disclosed having a desirable balance of impact resistance, crease stress whitening, and melt viscosity. These compositions are useful in thin guage ABS films.

Abstract: A curable polyester molding composition incorporating an elastomeric low profile additive dispersed in voided rubbery particle form throughout the composition is used in association with a compatibilizing agent to form a molded thermoset article having very smooth, light reflective, class A surfaces and having a matrix fracture energy which is comparable to articles formed from similar or identical molding compositions which are free of low profile additives. The low profile additive is an epoxidized elastomer or block copolymer having at least one flexible elastomer block and one monovinyl aromatic block. The compatibilizing agent is a copolymer having a diene polymer backbone which is compatible with the elastomer or the flexible diene block of the low profile additive, with constituents which are compatible or reactive with the polyester being grafted or adducted onto the diene polymer backbone.

Abstract: High impact polystyrene resins are provided having a surprisingly good combination of toughness and gloss characteristics. Such resins contain small (i.e., 0.1 to 0.4 micron) capsule morphology rubber particles in combination with relatively small (i.e., 0.25 to 1 micron) entanglement morphology rubber particles. It has been found that such resins are capable of providing Izod impact strength values in the range of 2.5 to 3.5 ft-lb/in (133.4 to 186.7 J/m) and higher at an overall volume average rubber size of less than 0.4 micron with corresponding gloss values in excess of 90 percent.

Abstract: A method is provided for continuous mass polymerization of acrylonitrile-butadiene-styrene type thermoplastics. The method involves charging a liquid feed comprising a vinylidene aromatic monomer, an unsaturated vinyl nitrile monomer and a synthetic butadiene polymer dissolved therein into a grafting reactor to prereact the liquid mass to form grafted rubber continuous phase polymeric product. The product from the grafting reactor is then charged to a phase inversion reactor where free rigid copolymer in monomer is the only continuous phase, and where dispersed particles of grafted rubber with occluded rigid copolymer and monomer are immediately formed from the product of the grafting reactor. The second polymerization product, which is coming out from the phase inversion reactor, is then charged to a finishing reactor wherein the material is further polymerized to form a third polymerization product which then can be devolatilized to provide a final thermoplastic composition.

Abstract: Graft copolymerized maleimide-modified, impact resistant monovinylidene aromatic copolymer compositions have substantially improved impact strength and fatigue resistance properties when the swelling index thereof is 12 or greater and when the numerical difference in maleimide monomer content as between the grafted copolymer and matrix copolymer portions thereof differ by no more than 9 percentage points from each other. Such compositions are conveniently prepared by mass, solution or mass/suspension graft copolymerization processes and by deferring the addition of at least about 30 percent of the maleimide monomer ingredient to a point in the process after (and preferably only shortly after) phase inversion of the dissolved impact modifying rubbery polymer ingredient.

Abstract: Disclosed are graft copolymers of polyolefins and a method of preparing said graft copolymers. The method comprises irradiating a mass of olefin polymer particles and thereafter treating the mass of particles with a vinyl monomer in liquid form. A nonoxidizing environment is maintained throughout the process while free radicals produced in the olefin polymer by the irradiation are present, thereby preventing degradation of the polymer. In a final step, residual free radicals are deactivated, and any unreacted monomer is removed.

Abstract: Addition polymers of ethylenically unsaturated monomers are provided comprising a 5-, 6- or 7-membered polymer unit formed from a copolymerizable, unsaturated, chain transfer agent containing a labile hydrogen and capable of forming by means of a hydrogen shift mechanism a free radical having 5, 6 or 7 atoms between and including the .alpha.-carbon of the ethylenically unsaturated group and the labile hydrogen.

Abstract: Graft copolymers are disclosed which comprise an olefin borane-containing homopolymer or copolymer backbone polymer having radically polymerized polymeric segments chemically bonded as side chains or as a chain end. A borane-containing diene homopolymer or a copolymer of a diene and/or at least one alpha-olefin having from about 2 to 22 carbon atoms copolymerized with another monomer containing organoborane functional groups can be used as a backbone polymer to prepare the graft copolymers of the present invention. Under oxidation conditions, the borane group becomes the reaction site for the radical polymerization and copolymerization. Radical polymerizable monomers, such as methyl methacrylate, styrene, alpha-methylstyrene, acrylonitrile and the like, can be polymerized to yield high molecular weight graft copolymer. By this synthetic route, high graft efficiency is observed with only a very low concentration of homopolymer being produced.

Abstract: A process for the continuous preparation of high-impact polystyrene-acrylonitrile (ABS) by free radical-initiated polymerization of a mixture of from 60 to 90% by weight of at least one vinylaromatic monomer and from 10 to 40% by weight of least one further ethylenically unsaturated monomer, in the presence of from 5 to 30% by weight, based on the sum of the monomers, of polybutadiene having a solution viscosity (5% strength by weight in styrene at 25.degree. C.) from 25 to 95 mPa.s and in the presence or absence of a solvent, in at least three consecutive reactors operated essentially without back-mixing, at from 50.degree. to 170.degree. C., phase inversion taking place in one of the reactors, involves carrying out the polymerization as far as phase inversion at 90.degree. C. or below and initiating the polymerization by free radicals from the decomposition of tert-butyl peresters whose half life period at 90.degree. C.

Abstract: A particulate graft polymer A ofA1: a grafting base based on a polydiene rubber A1 of, based on A1,A11: 70 to 100% by weight of a polymerizable diene, andA12: up to 30% by weight of a copolymerizable, ethylenically unsaturated monomer having a first graft sheath A2 of, based on A2,A21: 75 to 99.8% of at least one C.sub.1 -C.sub.8 alkyl acrylate A21,A22: 0.1 to 5% by weight of at least one polyfunctional, crosslinking monomer A22,A23: 0.1 to 20% by weight of at least one monomer A23 containing one or more acidic or basic groups, and a second graft sheath A3 comprising, based on A3,A31: 40 to 89.9% by weight of at least one aromatic vinyl monomer A31,A32: 10 to 49.9% by weight of at least one polar, ethylenically unsaturated monomer A32,A33: 0.1 to 20% by weight of at least one monomer A33 containing one or more basic or acidic groups, andA34: up to 5% by weight of at least one polyfunctional, crosslinking monomer A34,A23 and A33 in each case being different groups.

Abstract: Particulate graft copolymers for matt thermoplastic molding materials contain a base and a graft sheath. The base contains 75 to 99.8% of at least one alkyl acrylate, from 0.1 to 5% of at least one polyfunctional, crosslinking monomer having at least two ethylenic double bonds which are not conjugated in the 1,3-position, and from 0.1 to 20% of at least one ethylenically unsaturated monomer having one or more acidic groups. Alternatively, the base may contain at least 50% of one or more dienes, up to 50% of at least one further ethylenically unsaturated monomer, and up to 15% of at least one ethylenically unsaturated monomer having one or more acidic groups. The sheath contains from 0 to 99.8% of at least one aromatic vinyl monomer, from 0 to 99.8% of at least one polar, copolymerizable, ethylenically unsaturated monomer, from 0.1 to 20% of at least one ethylenically unsaturated monomer having one or more basic groups, and from 0.1 to 10% of at least one hydroxyalkyl (meth)acrylate.

Abstract: The invention relates to a polymer mixture comprisingA) 55-90% by weight of an aromatic polycarbonate (A1) or a mixture of an aromatic polycarbonate (A1) and a polyalkylene terephthalate (A2);B) 10-30% by weight of a graft copolymer built up from a diene rubber graft base on which at least one of the following vinyl monomers has been grafted: styrene, acrylonitrile, methyl methacrylate;C) 0-15% by weight of a copolymer of styrene, alphamethyl styrene, methyl methacrylate or mixtures thereof and acrylonitrile, methacrylonitrile, methyl methacry late or mixtures thereof, the percentages by weight being calculated with respect to the sum of the constituents A, B and C, the diene rubber graft base having a monodisperse particle size distribution having such a narrow particle size distribution that the diameter of more than 50% by weight of the particles lies between 200 and 300 nanometers and the diameter of more than 70% by weight of the particles lies between 200 and 400 nanometers.

Abstract: There are disclosed a graft copolymer formed by grafting a styrenic monomer onto a high polymer having double bonds in the side chain to constitute highly syndiotactic polystyrenic chain as the graft component, the graft copolymer having a content of graft component of 0.005 to 99% by weight and a reduced viscosity of 0.01 to 30 dl/g as measured at a concentration of 0.05 g/dl in 1,2,4-trichlorobenzene at 135.degree. C. or a melt index of 0.001 to 500 g/10 minutes as measured at 300.degree. C. under a load of 2.16 kg; a process for efficiently producing the above graft copolymer using a catalyst comprising specific components; and a resin composition comprising the above graft copolymer, a highly syndiotactic styrenic polymer or other thermoplastic resin and, when necessary, an inorganic or organic filler. The above graft copolymer and resin composition are excellent in resistance to heat and chemicals, electrical properties, moldability, compatibility, impact resistance, etc.

Abstract: A novel 2-substituted butadiene block copolymer is provided which provides adhesives having superior adhesion and tolerance to oil contaminated surfaces. The elastomeric block has a glass transition temperature of less than about minus 65.degree. C. with the 2 substituent being an alkyl group.

Abstract: Stable aqueous artificial latices having a core-shell structure are prepared from two otherwise incompatible polymers in a blend also including a copolymer of said polymers. For example, an artificial latex in which the particles have a styrene-acrylonitrile core and an EPDM shell can be prepared.

Abstract: A tire treadstock elastomer having reduced hysteresis is prepared by (1) preparing a living polymer by anionic polymerization of a conjugated diene or copolymerization of a conjugated diene with a monovinyl aromatic hydrocarbon, (2) endcapping the living polymer with at least 2.2 equivalents, preferably 3 to 15 equivalents, of a vinyl substituted bicyclic or tricyclic (preferably bicyclic) hydrocarbon, (3) quenching and recovering the endcapped polymer and (4) curing the endcapped polymer using a conventional rubber curing recipe to form an elastomer having reduced hysteresis. This elastomer either alone or blended with a conventional treadstock rubber may form a tire treadstock. The preferred endcapping agent is 2-vinylnaphthalene.

Abstract: Rubber-modified styrene resins with excellent impact resistance are prepared by formulating a feed from a styrene-based monomer, or a mixture thereof with comonomers and high-viscosity rubber, an organic peroxide, and, if necessary, all inert organic solvent, preheating and continuously supplying the feed to one end of a plug flow type reactor equipped with an agitator, performing the preliminary polymerization to a conversion sufficiently high for the transformation of the rubber in the feed into particles while controlling the weight average particle diameter of the rubber particles to 0.8 to 5 .mu.m, withdrawing the prepolymerized feed from the other end of the reactor, and supplying it to a following plug flow type reactor for continuous enhancement of tile conversion.

Abstract: There is a demand for very clear tough polymers or polymer blends, particularly in the packaging industry. Crystal polystyrene is clear but lacks toughness. HIPS is tough but lacks the required clarity. Blends of styrene-ester polymers with a very small amount of HIPS do provide a very clear tough polymer alloy.

Abstract: A propylene (co) polymer terminated with a reactive group and a process for the preparation of the same.A graft copolymer having a specific side chain and a process for the preparation of the same.The propylene (co) polymer is usable as a radial- or ion-polymerizable propylene macromonomer or as an intermediate for the preparation of a block polymer. Examples of the application thereof include compatibizing agent for polymers, light- or laser-curable plastic, viscosity index and surface modifier.The graft copolymer is useful as a surface modifier or compatibilizing agent for polypropylene or a dispersant for fillers.

Abstract: A thermoplastic resin composition comprising (A) 45 to 99% by weight of a graft copolymer obtained by special graft polymerization of a monomer (b) such as an aromatic vinyl compound, a methacrylic ester, etc. in the presence of grafted polymer rubber (a), and (B) 55 to 1% by weight of a thermoplastic aromatic polyester resin can yield shaped articles excellent in impact resistance, chemical resistance, etc. with excellent processability.

Abstract: A method for preparing a polyolefine-vinyl composite, in which method about 10-200 weight fractions of vinyl monomer and about 0.01-4.0 weight fractions of a free radical polymerization initiator, based on 100 weight fractions of vinyl monomer, are impregnated in 100 weight fractions of polyolefine particles by slowly mixing these at a temperature of about 20.degree.-100.degree. C. while continuously or discontinuously adding about 1-60% by weight of water, based on the total weight of the vinyl monomer and the polyolefine, during the maintenance of the particle structure of the polyolefine, is disclosed. A water suspension is prepared by adding water and stabilizing agents to the above-mentioned mixture after a completed impregnation. The total quantity of water is about 80-1000 weight fractions, based on 100 weight fractions of polyolefine+vinyl monomer. The temperature of the water suspension is then increased for polymerizing the vinyl monomer.

Abstract: Bottle gaskets are provided from a thermoplastic composition comprising a homogeneous blend of butyl rubber with other thermoplastic polymer. The gaskets provide an effective seal at a moderate pressure but permit venting at a higher pressure. They can be made by inserting molten heated thermoplastic material into the bottle cap and moulding it in the cap and cooling it to form the gasket.

Abstract: Flame-retardant, thermoplastic copolymers and processes for making them are disclosed. The compositions are copolymers of a vinyl aromatic monomer, a vinyl phosphonic acid derivative, and optionally, an unsaturated organic diacid, ester, or anhydride that are grafted onto a rubber. Processes for making polymers having high molecular weight, good mechanical properties, and a high level of evenly distributed, chemically incorporated vinyl phosphonate flame retardant are also disclosed.

Abstract: A process for producing a rubber-modified thermoplastic resin, which comprises polymerizing (B) 30-100% by weight of an aromatic alkenyl compound monomer and/or an alkyl (meth)acrylate monomer and (C) 70-0% by weight of at least one other monomer compound copolymerizable therewith, in the presence of (A) a hydrogenated diene copolymer obtained by hydrogenating a diene copolymer comprising a rndom copolymer of 50% by weight or more of at least one conjugated diene and 50% by weight or less of an alkenyl aromatic compound until at least 70% by weight of the olefinic unsaturation of the diene copolymer is hydrogenated.

Abstract: A multi-layered polymer having (a) a core layer of an aromatic vinyl polymer, (b) an intermediate layer of a butadienic rubbery polymer and (c) an outer layer of an aromatic vinyl glassy polymer, the amount of the components (a), (b) and (c) being 12 to 42 weight %, 48 to 78 weight % and 10 to 40 weight %, respectively, provides a thermoplastic resin composition excellent not only in impact strength, especially in impact strength at low temperatures, but also in, in the case of containing a coloring agent, color-stability including less mottlings, and giving a molded article improved in preventing occurrence of delamination around the gate region.

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 weather resistant impact modifier for thermoplastic resins and a blend with the thermoplastic resin are disclosed. The modifier comprises a graft copolymer having a multi-layered structure which is obtained by graft polymerization of (c) 10-100 parts by weight of an aromatic vinyl compound or a monomer mixture mainly composed of an aromatic vinyl compound in a first stage and 10-100 parts by weight of a methacrylic ester or a monomer mixture mainly composed of a methacrylic ester in a second stage,(b) to 100 parts by weight of an elastomer obtained by polymerizing 98-60 parts by weight of a monomer mixture composed of 50-99.95% by weight of an acrylic ester, 0-50 wt % of a copolymerizable monomer and 0.05-5% by weight of a polyfunctional monomer,(a) in the presence of 2-40 parts by weight of a butadiene elastomer having a degree of swelling of 5-40 and an average particle size of not smaller than 0.15 .mu.m (wherein the total of (a) and (b) is 100 parts by weight).

Abstract: Flame-retardant, thermoplastic copolymers and processes for making them are disclosed. The compositions are copolymers of a vinyl aromatic monomer, a vinyl phosphonic acid derivative, and optionally, an unsaturated organic diacid, ester, or anhydride that are grafted onto a rubber. Processes for making polymers having high molecular weight, good mechanical properties, and a high level of evenly distributed, chemically incorporated vinyl phosphonate flame retardant are also disclosed.

Abstract: Radial block copolymers characterized by the formulas: (1) (pS-pI).sub.n X and (2) (pS-pI-pB).sub.n X where pS is polystyrene, pI is polyisoprene, pB is butadiene, X is a residue of a multifunctional coupling agent used in the production of the radial block copolymer, and n is a number greater than 2 representative of the number of branches appended to X; hot-melt adhesive compositions constituted of said radial block copolymers, and articles of manufacture produced therefrom. These copolymers possess blocks of high average molecular weight polystyrene (10,000 to 25,000) and an overall average molecular weight (90,000 to 380,000) such that when blended in requisite proportions with a compatible tackifier resin, preferably also a secondary tackifying resin or plasticizing oil, and stabilizer, superior hot-melt adhesive compositions can be formed.

Abstract: A grafted copolymer containing low cis-polybutadiene having a Mooney viscosity of 30 to 40 as a rubber component, and 30% by volume or more of particles of said rubber component becoming non-spherical rubber particles when molded into a molded article, is suitable for use as a low gloss agent which is usable in the fields of internal and external automotive trims, exterior parts of household electric appliances, etc.

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: Acrylonitrile-butadiene-styrene-ester compositions having a unique rubber phase morphology are prepared by a continuous mass polymerization process. The compositions have an improved balance between impact and tensile strengths and gloss.

Abstract: New polymeric compositions comprising:(a) a linear copolymer constituted by four alternating blocks, which can be represented by the formula (I) or (II)B.sub.1 --T--A.sub.1 --B.sub.2 --A.sub.2 (I)orB.sub.1 --A.sub.1 --B.sub.2 --T--A.sub.2 (II)wherein:B.sub.1 and B.sub.2 are polydienic blocks, preferably polybutadienic blocks;A.sub.1 and A.sub.2 are polyvinylaromatic blocks and preferably polystyrenic blocks;T is a portion of random copolymer formed by dienic and vinylaromatic monomer units;(b) a linear copolymer constituted by two blocks, which can be represented by the formulae (III) or (IV)B.sub.3 --T--A.sub.3 (III)orB.sub.3 --A.sub.3 (IV)wherein:B.sub.3 is a polydienic block;A.sub.3 is a polyvinylaromatic block; andT has the above seen meaning.The polymeric composition, which can be blended with polystyrene, can be obtained both by blending the individual components, and by means of novel and original synthesis processes which make it possible both (A) and (B) components to be obtained simultaneously.

Abstract: The present invention provides a process for preparing thermoplastic resin compositions having excellent HCFC resistance which comprises:a first step wherein 50 to 90 parts by weight of a monomer mixture of 50 to 80% by weight of a vinyl cyanide, 20 to 50% by weight of an aromatic vinyl compound and 5% by weight or less of an unsaturated carboxylic acid or esters thereof or a vinyl acetate are graft-polymerized in the presence of 10 to 50 parts by weight of a rubber latex and also in the presence of 0.001 to 2.0 parts by weight of a polymerization inhibitor to prepare a graft polymer(A);a second step wherein 100 parts by weight of a monomer mixture of 50 to 80% by weight of a vinyl cyanide, 20 to 50% by weight of an aromatic vinyl compound and 5% by weight or less of an unsaturated carboxylic acid or esters thereof are polymerized, while adding 2.

Abstract: In a process for producing a thermoplastic resin by emulsion polymerization using a conjugated diene rubber, an aromatic vinyl compound and a vinyl cyanide compound, and by successive flocculation and direct pelletizing, the direct pelletizing is effected in the presence of a phenolic compound represented by ##STR1## wherein R.sup.1 and R.sup.4 are each hydrogen or methyl, and R.sup.2 and R.sup.3 are each an alkyl of 1 to 9 carbon atoms. The use of the phenolic compound is effective to prevent the resin from thermal deterioration during the direct pelletizing, thereby producing the thermoplastic resin excellent in properties such as impact resistance.

Abstract: A process for the continuous preparation of ABS polymers by free-radical-initiated polymerization of, in particular, styrene and acrylonitrile in the presence of polybutadiene, in the presence or absence of a solvent, in a reactor cascade comprising at least 3 stirred reactors operating essentially without back-mixing, at least some of which contain internal cooling tubes for dissipating the heat of polymerization, at from 50 to 180.degree. C., phase inversion taking place in one of the reactors which contains means for generating a high shear force, and an apparatus for carrying out the process comprising an essentially cylindrical/tubular vessel jacket and a cylindrical internal element connected to a stirrer shaft by rotational force and having an external diameter which is slightly less than the internal diameter of the vessel jacket.

Abstract: An improved process for the polymerization of styrene is provided. The process comprises feeding styrene monomer and a mixture of peroxides, which decompose at progressively higher temperatures, into a prepolymerization vessel maintained at 200.degree.-270.degree. F. About 20-40% of the styrene in this vessel is converted to polymer (depending on temperature and residence time) and then fed to an extruder where the polymer is raised in temperature by passage through a heat exchanger or through the heated throat of the extruder. During this heating, the polymerization is completed in seconds to minutes in an extruder as the peroxides decompose in sequence as the temperature rises. A final devolatilization zone is provided to remove the final traces of monomer. The molten polymer is then passed through a die and stranded or hot die face cut.

Abstract: There is disclosed a monovinylidene aromatic polymer resin having a specific rubber particle size distribution that provides surprisingly improved combinations of product properties, such as gloss, impact resistance and tensile strength. Such resin has a first group of smaller particles having a volume average particle diameter of from about 0.2 to about 0.6 micrometers and a second group of larger particles having a volume average particle diameter of from about 2.5 to about 5 micrometers. In these resins it is further necessary in this specific rubber particle size distribution, based on 100 parts by weight rubber or rubber equivalent, that (a) particles constituting from about 20 to about 60 parts by weight of the rubber have diameters of from about 0.1 to about 0.

Abstract: A multilayer packaging structure for microwave food reheating applications or for sterilized hot filling is provided having an outer layer prepared from a blend of polyphenylene ether and a high impact polystyrene. The polyphenylene ether-high impact polystyrene layer is useful as a structural support layer and provides resistance to distortion and burn through during microwave reconstitution or hot filling. The PPE/HIPS blend layer serves to increase the high temperature performance of the coextruded structure without sacrificing the thermoformability characteristics generally associated with HIPS based monolayer or multilayer structures. The ethylene vinyl alcohol or polyvinylidene chloride layers act as the oxygen barrier to prevent food spoilage and the polyolefin layer acts as a moisture barrier.

Abstract: A resin composition comprising a graft copolymer of a rubbery polymer having a vinyl cyanide compound and an aromatic vinyl compound grafted thereon, and a copolymer comprising a vinyl cyanide compound and an aromatic vinyl compound. A molded article of the resin composition is characterized with improved coating performances.

Abstract: Impact-resistant polystyrene acrylonitrile (ABS) is prepared by free radical polymernation of monomeric styrene and acrylonitrile or equivalents thereof in the presence of preformed, dissolved polbutadiene as a grafting base, the solvents used being in particular ethylbenzene and, at least from time to time, the monomers, and phase inversion taking place when the process has progressed to a certain point, in two or more reaction zones, by a continuous process in which the first reaction zone is present at least in duplicate and is in the form of a stirred kettle in each case, so that one stirred kettle is operated batchwise and alternately with the other in such a way that the reaction mixture is polymerized until phase inversion is complete or the initiator has been consumed, and the particular kettle content is then fed continuously to a second reaction zone in the form of a tube reactor.

Abstract: Disclosed is a process for producing a styrene polymer composition, which comprises polymerizing styrene monomer using a catalyst comprising (A) aluminoxane and (B) a compound of the group IV B transition metal in the periodic table, in the presence of rubber-like elastomer.The resin composition obtained thereby is superior in heat resistance, and impact strength, and utilized as the starting material for various moldings.

Abstract: A feed containing 100 parts by weight of reactants consisting of 88 to 98% by weight of a styrene-based monomer or its mixture with other comonomers and 2 to 12% by weight of high-viscosity rubber with a viscosity of 400 to 2,000 centipoises in a 5% by weight styrene solution at 25.degree. C., 0.01 to 0.2 part by weight of an organic peroxide, and 0 to 30 parts by weight of an inert organic solvent is supplied continuously to the first complete mixing type reactor where it is polymerized under the condition prevailing before the rubber phase inversion, the initial reaction mixture is withdrawn continuously and supplied to the second complete mixing type reactor where the rubber is transformed into particles with the conversion of the monomers in the reactants held at 40% by weight or less, and the conversion is raised in the following reactor to yield impact-resistant rubber-modified styrene resins containing rubber particles with a weight average particle diameter of 1.5 to 4 .mu.m.

Abstract: A process for preparing continuously tapered polymers and copolymers having a continuous change in microstructure along the polymer backbone is disclosed. The process produces polymers and copolymers with multiple glass transition temperatures of very small energy absorption, i.e. no definable glass transition temperature. The polymers have a flexible chain end and they progressively become stiffer along the length of the chain.

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.