Abstract: A composition to be used for the manufacture of mono- or multilayer films for food-wrap applications comprising from 5 to 40 wt % of a styrenic block copolymer, a polyolefin in an amount of at least 40 wt % and optionally a resin which is compatible with the hydrogenated poly(butadiene) blocks of the styrenic block copolymer in an amount of from 0 to 25 % wt, wherein all weight percentages are relative to the weight of the complete composition; a styrenic block copolymer to be used in said composition, and mono- or multi-layer films comprising said composition.

Abstract: A polymer composition and a thermoplastic elastomer composition containing 1,2-polybutadiene having a 1,2-bond content in the butadiene unit of 70% by weight or more, a melting point in the range of 50 to 140° C., a total halogen content of 30 ppm or less, a viscosity ? in the range of 400 to 1200 poise when measured with a slit die rheometer at a shear rate of 5113 sec?1 at 120° C., a viscosity ? in the range of 300 to 1000 poise when measured with a slit die rheometer at a shear rate of 5113 sec?1 at 150° C., and a viscosity ? in the range of 200 to 800 poise when measured with a slit die rheometer at a shear rate of 5113 sec?1 at 180° C. exhibit excellent moldability, visual appearance and scratch resistance.

Abstract: An objective of the invention is to provide a rubber composition which has satisfactory processability and dimension stability, and the like, gives a vulcanized rubber exhibiting excellent wearing resistance and tensile strength, and the like, and thus is useful in a belt, a hose and a tire and the like, as well as a crosslinked rubber particle for obtaining such rubber composition. A rubber composition of the invention comprises [1] a crosslinked rubber particle comprising as repeating units (a) 30 to 94.89% by weight of a conjugated diene unit, (b) 5 to 69.89% by weight of an aromatic vinyl unit, (c) 0.01 to 10% by weight of a monomer unit having at least two polymerizable unsaturated group, (d) one polymerizable unsaturated group and an amino group, a hydroxyl group and an epoxy group and (e) 0.

Abstract: The instant invention teaches a method for forming a syndiotactic 1,2-polybutadiene product having a syndiotacticity of more than 66.5% and a melting temperature of more than about 100° C. The method includes polymerizing 1,3-butadiene in solution with a solvent, in the presence of catalytically effective amounts of: (a) an organomagnesium compound; (b) a chromium compound; and, (c) a dihydrocarbyl hydrogen phosphite. The present invention also contemplates a product of the method and an article made from the product.

Abstract: The present invention provides a rubber composition which is balanced in wet skid resistance, low-temperature properties and low fuel consumption and which is suitable as a material for all-weather tire. This rubber composition comprises a random copolymer A having a glass transition temperature of -20.degree. C. or higher, a random copolymer B having a glass transition temperature of -50.degree. C. or lower, and a block copolymer C composed of said two copolymers as block units. The copolymers A, B and C can be produced by copolymerizing an aromatic vinyl compound and a conjugated diene using an alkali metal-based catalyst.

Abstract: Crystalline propylene (co)polymers modified by grafting with a vinylpolybutadiene having 1,2-structure content of at least 10%.Said (co)polymers are reacted with a liquid vinylpolybutadiene in the presence of a non-peroxidic radical initiator at a temperature in the range 200.degree. to 350.degree. C., the liquid vinylpolybutadiene having a 1.2-structure content of at least 10% and being generally used in amounts within the range 0,5 to 20% by weight.

Abstract: Crystalline propylene (co)polymers modified by grafting with a vinylpolybutadiene having 1,2-structure content of at least l0%.The (co)polymers are reacted with a liquid vinylpolybutadiene in the presence of a non-peroxidic radical initiator at a temperature in the range 200.degree. to 350.degree. C., the liquid vinylpolybutadiene having a 1,2-structure content of at least 10% and being generally used in amounts within the range 0.5 to 20% by weight.

Abstract: A polyester composition principally comprising a polyester and a specific block copolymer having terminal hydroxyl groups. The polyester composition is excellent not only in heat resistance, solvent resistance and processability, but also in shock resistance.

Abstract: The present invention relates to a covering based on thermoplastic elastomers, especially a floor covering.The matrix constituting such a covering is an alloy containing, as base, a styrene-based thermoplastic elastomer, as reinforcement, a styrene-based polymer and, as flexibilizer, an olefin polymer.The coverings thus obtained satisfy the wear standards of a floor covering, can be calendered and exhibit good resistance to cigarette burns.

Abstract: A polyester composition principally comprising a polyester and a specific block copolymer having terminal hydroxyl groups. The polyester composition is excellent not only in heat resistance, solvent resistance and processability, but also in shock resistance.

Abstract: An ozone and heat resistant polymer blend prepared from a first solid, high acrylonitrile nitrile/conjugated diene copolymer and a second, solid, fully hydrogenated nitrile/conjugated diene copolymer, blended in a ratio of about 70:30 to about 50:50.

Abstract: A hydrogenated block copolymer having a number-average molecular weight of 40,000-700,000, obtained by hydrogenating at least 80% of the olefinic bonds of a block copolymer having in the molecule at least one each ofa polymer block A composed of 90% by weight or more of a vinyl aromatic compound,a polybutadiene polymer block B having a 1,2-vinyl structure of 30-70%, anda polybutadiene polymer block C having a 1,2-vinyl structure of less than 30%,in which block copolymer the blocks A, B and C are contained at a specific ratio, or a unit of the block copolymer is bonded, via a coupling agent residue, to at least one polymer block unit of the blocks A, B and C and thereby the polymer molecular chain is extended or branched; and a thermoplastic resin composition comprising the hydrogenated block copolymer.

Abstract: An elastomer barrier composition comprises a melt blend of syndiotactic 1,2-polybutadiene, a terpolymer of ethylene, vinyl acetate and vinyl alcohol, and a compatibilizing agent. The melt blend is formed under suitable mixing and shear conditions such that the terpolymer exists as a separate domain in generally a flat or plate-like form. The elastomer barrier material can be utilized in rubber compositions such as in the innerliner of the tire.

Abstract: Polyisoprenes having a high content of 1,2- and 3,4-structural units, a process for their preparation, and their use.The previous processes for the preparation of polyisoprene having a high content of 1,2- and 3,4-structural units were still unsatisfactory in terms of the cocatalyst employed.The use of ethylene glycol dialkyl ethers of the formulaR.sub.1 --O--CH.sub.2 --CH.sub.2 --O--R.sub.2in which R.sub.1 and R.sub.2 are alkyl groups having different numbers of C atoms, from the group consisting of methyl, ethyl, n- and isopropyl and n-, iso-, sec.- and tert.-butyl, has, in particular, the advantage that the "living polymers" formed during the anionic polymerization are not damaged.The production of tires and damping elements using these polyisoprenes.

Abstract: A thermoplastic blend with the ability to absorb less than 40% of an oil, and having a superior tensile strength comprises about 80 to about 20 phr of an elastomeric block copolymer having the general configuration A-B-A, wherein the B block is a butadiene hydrocarbon block consisting of about 35 to about 55 mole percent of condensed butadiene units in the 1,2 configuration, and about 20 to about 80 phr of a block copolymer having the general configuration A-B-A, wherein the B block is a hydrogenated butadiene hydrocarbon block consisting of about 18 to about 34 mole percent of condensed butadiene units in the 1,2 configuration.

Abstract: It has been determined that certain rubbery polymers having multiple glass transition temperatures can be utilized in making tires which have improved rolling resistance, improved wet skid resistance, and outstanding tread wear. These rubbery polymers are derived from at least one conjugated diolefin monomer, have a first glass transition temperature which is between -110.degree. C. and -20.degree. C. and have a second glass transition temperature which is between -50.degree. C. and 0.degree. C. These rubber polymers can be homopolymers of conjugated diolefin monomers, copolymers of more than one conjugated diolefin monomer, or copolymers derived from at least one conjugated diolefin monomer and at least one vinyl aromatic monomer.

Abstract: ABC block copolymers on the basis of butadiene, isoprene and optionally styrene, are provided by a polymerization process wherein the resultant block copolymer comprises:about 40 to 75 wt % of a block A based on butadiene (uniformly distributed vinyl group content less than about 15 wt %),up to about 25 wt % of a block B based on butadiene and isoprene (vinyl content less than about 15 wt %) or based on butadiene (vinyl content more than about 75 wt %)about 20 to 55 wt % of a block C based on butadiene and isoprene (vinyl content more than about 75 wt %). The ABC block copolymers are useful for the production of tire treads.

Abstract: A rubber composition containing at least 20% by weight of a styrene-butadiene block copolymer consisting of a block (A) and a block (B) characterized in that: (i) the block (A) is a styrene-butadiene copolymer block having the content of styrene of 10-80% by weight and the average content of the vinyl bonds in the butadiene portion of 30-70% by weight; (ii) the block (B) is a polybutadiene block with the average content of the vinyl bonds in the butadiene portion being not more than 60% by weight (iii) the styrene-butadiene block copolymer contains at least 20% by weight of each of the block (A) and the block (B); (iv) the average content of the vinyl bonds in the butadiene portion of the block (A) is greater by at least 5% by weight than that of the block (B); (v) the glass transition temperature of the block (A) is higher by at least 30.degree. C.

Abstract: Disclosed herein are a polypropylene resin composition comprising 100 parts by weight of propylene homopolymer showing a stereoregularity of a boiling heptane-insoluble part thereof of not less than 0.960 as an isotactic pentad rate obtained by .sup.13 C-NMR and 0.01 to 2 parts by weight of a hydrocarbon polymer having completely or partially saturated main hydrocarbon chain and at least one hydroxy group at an end of the main hydrocarbon chain, and a biaxially stretched film comprising the polypropylene resin composition.

Abstract: Rubber compositions for tires having low rolling resistance and excellent running stability consist mainly of a rubber blend consisting of 10-90% by weight of a high vinyl amorphous butadiene-styrene copolymeric rubber obtained by copolymerizing styrene with 1,3-butadiene and containing 3-30% by weight of bonded styrene and not less than 60% by weight of 1,2-bond in butadiene unit, and 90-10% by weight of a dienic rubber having a glass transition temperature of lower than -60.degree. C.

Abstract: Moldings having enhanced physical properties are made from compositions of a conjugated diene polymer, calcium carbonate and certain .alpha.,.beta.-unsaturated carboxylic modifiers.

Abstract: A rubber composition suitable for use in tire tread is disclosed, which contains at least 20 parts by weight of a block copolymer per 100 parts by weight of total rubber content. This block copolymer comprises (A) a polymer segment obtained by starting from conjugated diolefin and monovinyl aromatic hydrocarbon and having a content of monovinyl aromatic hydrocarbon bond of not more than 10% by weight and (B) a copolymer segment obtained by copolymerization of conjugated diolefin and monovinyl aromatic hydrocarbon and having a content of monovinyl aromatic hydrocarbon bond of 15-50% by weight.

Abstract: An elastomeric composition of the type used as a jacketing material for electrical wires and cables is shown having improved chemical, water and heat resistance. An ethylene/acrylic elastomer comprising a terpolymer of ethylene, methyl acrylate, and a cure site monomer is used as the base polymer and has blended therewith a polybutadiene. The polybutadiene has greater than 50% 1,2 polymerized units and has a molecular weight between about 1,500 and 25,000 grams/mole.

Abstract: A rubber composition adapted to be used as a tread rubber is disclosed. The rubber composition has remarkably improved resistance against heat generation, breakage resistance, wear resistance, wet skid resistance and low-temperature brittleness, and consists mainly of a rubber blend consisting of 20-95 parts by weight of a styrene-butadiene block copolymer having a specifically limited structure and 80-5 parts by weight of a diene rubber.

Abstract: A thermosetting composition in which high vinyl diolefin polymer chosen from among homopolymers of 1,3-butadiene and copolymers of 1,3-butadiene with styrene are admixed with about 15 to about 35 weight percent of the total polymer phase of a normally solid, elastomeric 1,3-butadiene homopolymer having high vinyl and low vinyl segments in a weight ratio of about 60:40 to about 40:60. Preferably the thermosetting composition also contains from about 15 to about 35 weight percent of the total polymeric phase of a normally solid rubbery polymer of isobutylene.

Abstract: An uncrosslinked thermoplastic elastomer composition comprising:(A) 35-95% by weight of a 1,2-polybutadiene having a 1,2-configuration content of 70% or more, a crystallinity of 5-40% by weight and [.eta.] of 0.7 dl/g or more as measured at 30.degree. C. in toluene,(B) 1-20% by weight of an isobutylene polymer or an isobutylene-isoprene copolymer (preferably having a degree of unsaturation of 0-5 mole % and a viscosity average molecular weight of 7,000-80,000),(C) 5-40% by weight of a polybutadiene rubber having a 1,4-configuration content of 80% or more and(D) 0-30% by weight, preferably 5-30% by weight, of at least one member selected from the group consisting of isoprene rubber, natural rubber, acrylonitrile-butadiene rubber, styrene-butadiene rubber and ethylene-propylene type rubbers, wherein, preferably, (B)/{(C)+(D)}=2/1-1/20.

Abstract: The present invention is directed to (1) an epoxy compound identified as 3,3'-tetraglycidylsulfonyldianiline (referred to herein as 3,3'-TGDDS); (2) a thermosetting composition comprising 3,3'-TGDDS and a curing agent; (3) a thermosetting composition having improved resistance to moisture and to a reduction in the glass transition temperature at elevated temperatures when cured comprising (a) the above epoxy compound, i.e., 3,3'-TGDDS, (b) a polybutadiene rubber or mixture thereof, (c) an epoxy curing agent such as 4,4'-diaminodiphenylsulfone, (d) a free radical initiator and esterification catalyst for the polybutadiene rubber; and (4) a carbon fiber/rubber modified epoxy composite prepared from the thermosetting composition of (3).The 3,3'-TGDDS when melted and admixed with the polybutadiene rubber in a solventless system forms a homogeneous mixture which is stable for extended periods.

Abstract: Disclosed is a process of producing a fiber-reinforced rubber article having excellent mechanical strength and modulus of elasticity, and exhibiting rubber-like elasticity, by providing a rubber composition from a vulcanizable rubber material, a vulcanizing agent and 1,2-polybutadiene staple fibers in an amount of 1 to 20 parts by weight per 100 parts by weight of the rubber material, shaping and vulcanizing the rubber composition to provide a shaped, vulcanized article in which surface portions of said 1,2-polybutadiene staple fibers are vulcanized and cross-linked to the vulcanized rubber material matrix.