Abstract: A flame-retardant styrene resin composition comprising 100 parts by weight of a styrene resin, 1 to 25 parts by weight of at least one flame retarder (A) represented by the formula (I): ##STR1## wherein X is Br or Cl; and each of h and i is an integer of 2 to 5, and 1 to 25 parts by weight of at least one flame retarder (B) represented by the formula (II): ##STR2## wherein X is Br or Cl; each of l and m is an integer of 1 to 4; n means that the number of repeating units is 1 to 50; each of R.sup.1 and R.sup.2 is a C.sub.1-12 alkyl group; and each of R.sup.3 and R.sup.4 is a hydrogen atom, a lower alkyl group, an alkylphenyl group or a phenyl group, the total amount of (A) and (B) being 2 to 40 parts by weight. This composition has excellent heat resistance and excellent heat stability in addition to flame retardancy.

Abstract: A heat-resistant copolymer obtained by copolymerizing (A) 72-82 parts by weight of .alpha.-methylstyrene and (B) 26-18 parts by weight of acrylonitrile, characterized in that the copolymer contains (a) 0-15% by weight of monomer chain 13 (A)-(A)-(A)--, (b) 50% by weight or more of monomer chain --(A)-(A)-(B)--, and (c) 50% by weight or less of monomer chain --(B)-(A)-(B)--, the total of (a), (b) and (c) being 100% by weight. This copolymer is excellent in heat stability and moldability when molded at high temperatures, and the blending of this copolymer with other thermoplastic resins gives thermoplastic resins with excellent heat resistance.

Abstract: A thermoplastic resin composition obtained by graft-polymerizing 95 to 50 parts by weight of a monomer mixture comprising a vinyl aromatic compound monomer and an acrylic compound monomer and optionally a vinyl cyanide compound monomer in the presence of 5 to 50 parts by weight of a rubbery substance consisting of styrene-butadiene copolymers, characterized in that the rubbery substance comprises (A) 40 to 80% by weight of a styrene-butadiene copolymer having a number-average particle diameter of at least 0.05 .mu.m and less than 0.2 .mu.m, a gel content of 30 to 100% by weight and a bound styrene content of 10 to 40% by weight and (B) 60 to 20% by weight of a styrene-butadiene copolymer having a number-average particle diameter of 0.2 to 3 .mu.m, a gel content of 10 to 80% by weight and a bound styrene content of 10 to 40% by weight and the total content of the components (A) and (B) in the rubbery substance is at least 80% by weight.

Abstract: zs An amino group-containing copolymer which is composed of (A) butadiene, isoprene or both of them, (B) acrylonitrile and (C) a (meth)acrylate represented by the general formula (I): ##STR1## wherein R is H or CH.sub.3, R.sub.1 and R.sub.2 are independently alkyl groups having 2 to 8 carbon atoms, and X is an alkylene group having 2 to 4 carbon atoms, and has a polymer composition (weight %) of (A):(B):(C) of 30 to 89.9:10 to 50:0.1 to 20. Said multi-component copolymer is used as oil-resistant rubber, and is particularly excellent in resistance to growth of crack by solvent.

Abstract: A process for producing an olefin copolymer rubber by slurry-polymerizing ethylene, at least one .alpha.-olefin and at least one non-conjugated diene in a poor solvent for the copolymer in the presence of a catalyst consisting of an organometallic compound (the first component) and a transition metal compound (the second component), characterized by using, an organoaluminum compound as the first component of the catalyst, and using, as the second component, a modified vanadium compound obtained by contacting a vanadium compound with at least one compound selected from the group consisting of the compounds represented by the following formulas: ##STR1## wherein R is a hydrocarbon group of 1 to 20 carbon atoms and X.sub.1, X.sub.2 and X.sub.3 are independently halogen atoms or alkoxyl groups. This process can prevent a gel from being formed during polymerization.

Abstract: A rubber composition containing not less than 20% of a conjugated diene based polymer or copolymer. The polymer or copolymer is obtained by polymerizing a conjugated diene or copolymerizing the conjugated diene with at least one kind of other conjugated diene and an aromatic vinyl compound with use of a lithium initiator, and then reacting an isocyanate compound with active terminals of the thus obtained polymer or copolymer. The conjugated diene is butadiene or isoprene, while other conjugated diene is selected from pentadiene, 2,3-dimethylbutadiene as well as isoprene and butadiene, and an aromatic vinyl compound may be styrene, vinyltoluene, .alpha.-methylstyrene, etc. The rubber composition is applicable as tread portion, carcass, side wall portion of tires, vibration resistant rubber, window frame, hose, and various industrial articles.

Abstract: An aqueous dispersion of polymer particles each consisting essentially of (a) a syndiotactic 1,2-polybutadiene having 70% or more of unsaturated hydrocarbon groups in the side chains and having a melting point of 70.degree. C. or higher, (b) a polymer mixture of said polybutadiene (a) and other polymer in the form that (a) and (b) co-exist in the same particle, or (c) a copolymer obtained by graft-polymerizing a conjugated diene and/or other polymerizable monomer on said polybutadiene (a), each of said particles having an average diameter of 10 .mu.m or less.

Abstract: YA rubber composition for use in tire having improved rolling resistance, wet skid resistance and processability is disclosed, which comprises at least 20% by weight of a conjugated diolefin-vinyl-substituted aromatic hydrocarbon random copolymer. This random copolymer is produced by copolymerization with a particular initiator and coupling with a particular coupling agent, and has a content of vinyl-substituted aromatic hydrocarbon of 3-60% by weight, a content of tin bonded to copolymer of not less than 400 ppm and a Mooney viscosity (ML.sub.1+4.sup.100.degree.C.) of 20-200.

Abstract: A heat resistant thermoplastic resin composition comprising (a) 5 to 99% by weight of a poly(phenylene ether), (b) 95 to 1% by weight of a thermoplastic resin which is obtained by polymerizing in the absence of a rubber-like polymer a resin constituent mixture comprising an aromatic alkenyl compound, an alkenyl cyanide compound, and, if necessary, other alkenyl monomers copolymerizable with said monomers, and (c) up to 94% by weight of other styrenic resins, said thermoplastic resin (b) comprising (A) 1-50% by weight of a polymer having an alkenyl cyanide compound content of 1% by weight or more but less than 10% by weight, (B) 1-70% by weight of a polymer having an alkenyl cyanide compound content of 10% by weight or more but less than 20% by weight, (C) 5-90% by weight of a polymer having an alkenyl cyanide compound content of 20% by weight or more but less than 40% by weight, and (D) up to 70% by weight of a polymer having an alkenyl cyanide compound content of 40% by weight or more, and having a total alk

Abstract: A thermoplastic resin composition obtainable by blending 100 parts by weight of a mixture consisting of(A) 75 to 40% by weight of a propylene polymer,(B) 20 to 40% by weight of an ethylene-alpha-olefin copolymer, and(C) 5 to 30% by weight of a graft copolymer obtained by copolymerizing an aromatic vinyl compound and a polar vinyl compound in the presence of an ethylene-alpha-olefin copolymerwith(D) 0.1 to 5 parts by weight of an unsaturated dicarboxylic acid, an anhydride thereof or a mixture of the two, and(E) 0.01 to 0.3 part by weight of an organic radical-generating agent,and then subjecting the resulting blend to thermal treatment. Said composition has not only a high bending modulus inherently possessed by polypropylene resins but also remarkably improved coating property. Accordingly, the composition is useful as interior and exterior trim parts of automobiles and exterior trim parts of motorcycles.

Abstract: A non-hydrous soft contact lens comprising a copolymer comprising, as monomer units, 49.9 to 95 mole % of an acrylate represented by Formula (I) shown below, 0 to 10 mole % of acrylic acid or the specified ester thereof, 4.9 to 50 mole % of a methacrylate represented by Formula (II) shown below, and 0.1 to 10 mole % of a crosslinking monomer. ##STR1## wherein R.sup.1 is at least one selected from the group consisting of a particular straight chain fluoroalkyl group and a particular straight chain alkyl group. ##STR2## wherein R.sup.2 is a particular straight chain fluoroalkyl group. The present soft contact lens requires no sterilization by boiling, and has good resistance to stain, good oxygen permeability, good elastic recovery and good shape stability.A process for producing the above non-hydrous soft contact lens, comprising the step of subjecting a rigid precursor lens to treatment(s) of esterification and/or transesterification, is also disclosed.

Abstract: Liquid mobility is judged by the steps of filling the specimen in a specimen chamber formed in a specimen bed made of a transparent material just up to the level of the upper surface of the specimen bed, of pressing a liquid-absorbent material keeper for keeping a liquid-absorbent material horizontally to make the liquid-absorbent material contact with the specimen bed from the upper side of the specimen chamber, and of continuously detecting an intensity of a scattered light coming from the specimen in the specimen chamber with an optical detector consisting of a light emitting source and a light receiver and being disposed on the side of the lower surface of the specimen bed while the liquid-absorbent material is forced to contact the specimen bed. The liquid mobility is grasped in a short period of time.

Abstract: A diene polymer composition having improved fracture properties and a small change in the shape of extruded product is disclosed, which comprises at least 5% by weight of a copolymer composed of at least one conjugated diene (component A) having the following general formula: ##STR1## wherein R.sub.1 and R.sub.2 are a hydrogen atom or a methyl group, and 2,3-dimethylbutadiene (component B), said copolymer having a content of cis-1,4-bond of not less than 80%.

Abstract: Rubber compounds comprising a specific type of polyorganosiloxane of the following formula ##STR1## in which R and R' independently represent a hydrocarbon substituent and n is an integer of not smaller than 3 provided that at least 6 mole % of the substituents R and R' consists of a hydrocarbon group having Small's molecular attraction constant not smaller than 350. Carbon black is added to the polyorganosiloxane whereby various physical properties are improved including breaking strength, water and hot water resistances. The rubber compound may further comprise at least one organic rubber other than the above polyorganosiloxane.

Abstract: A magnetic recording medium is described, comprising a support having provided thereon a thin magnetic metal film, and a thin layer consisting essentially of at least one fluorinated polymer selected from 1,1-difluoroethylene polymer 1,1,2-trifluoroethylene polymer and the copolymer thereof being provided on at least one of the surface of the thin magnetic metal film and the surface of the support opposite to the thin magnetic metal film.

Abstract: A process for producing an internal-oxidized alloy, which comprises allowing a plasma generated in the presence of oxygen, a gas of an oxygen atom-containing compound or a mixture of oxygen and a gas of an oxygen atom-containing compound to act on an alloy consisting of at least two metal elements, thereby selectively oxidizing at least one metal element other than the matrix metal in said alloy. Particles of the internal-oxidized alloy thus obtained can, if necessary, be molded into a desired shape and sintered. Said process enables one to produce an internal-oxidized alloy at a high speed at a temperature of not more than 0.9 Tm (Tm: the melting point of the starting alloy) and does not require the step of separating an internal-oxidizing agent which step is required in the conventional process.

Abstract: A pressure-sensitive adhesive composition comprising as a base polymer a mixed block copolymer comprising a polymer block of a monovinyl-substituted aromatic compound and a polymer block of a conjugated diene compound. The pressure-sensitive adhesive composition is useful to seal, for example, corrugated board or carton.

Abstract: A process for producing an olefin copolymer rubber by slurry-polymerizing ethylene, at least one .alpha.-olefin and at least one non-conjugated diene in a poor solvent for the copolymer in the presence of a catalyst consisting of an organometallic compound (the first component) and a transition metal compound (the second component), characterized by using, an organoaluminum compound as the first component of the catalyst, and using, as the second component, a modified vanadium compound obtained by contacting a vanadium compound with at least one compound selected from the group consisting of the compounds represented by the following formulas: ##STR1## wherein R is a hydrocarbon group of 1 to 20 carbon atoms and X.sub.1, X.sub.2 and X.sub.3 are independently halogen atoms or alkoxyl groups. This process can prevent a gel from being formed during polymerization.

Abstract: A process for producing a plasma polymerized film, which comprises forming a plasma polymerized film on the surface of a substrate placed in a reaction zone by subjecting an organic compound containing gas to plasma polymerization utilizing low temperature plasma formed by pulse discharging, in which the time for non-discharge condition is at least 1 msec. and the voltage rise time for gas breakdown is not longer than 100 msec. The plasma polymerized film obtained has a small coefficient of friction, high lubricity, durability and heat resistance and is useful as a solid lubricating film, etc.

Abstract: A process for preparing large-sized polymer particles having a particle diameter in a range of 0.1 to 500 .mu.m by seeded polymerization is described, comprising:finely dispersing a polymerizable monomer in an aqueous medium to prepare a monomer dispersion in which a number average particle diameter of the resulting monomer droplets is not larger than that of seed particles, and a number average particle diameter in a semi-stable condition (Dm) of the monomer droplets satisfies, with a desired number average particle diameter of the final polymer particle as D, the following relation:0.5.times.D<Dm<3.5.times.Dcombining said monomer dispersion with a dispersion of seed particles to make the polymerizable monomer absorbed or adsorbed on the seed particles; andpolymerizing the polymerizable monomer in the presence of a polymerization initiator.