Abstract: The invention relates to a tire with a tread. The tread is composed of at least two defined elastomers having Tg's spaced apart by at least 55° C. to the exclusion of elastomers having Tg's between −30° and −85° C. The tread composition can be reinforced with either carbon black or a combination of carbon black and silica reinforcing fillers.

Abstract: The present invention relates to a tire tread compound that is highly loaded with silica. This compound offers the advantages of silica compounding without the need for solution SBR. More specifically, the tire tread rubber formulations of this invention offer an excellent combination of traction, treadwear and rolling resistance characteristics. The subject invention discloses a tire which is comprised of a generally toroidal-shaped carcass with an outer circumferential tread, two spaced beads, at least one ply extending from bead to bead and sidewalls extending radially from and connecting said tread to said beads; wherein said tread is adapted to be ground-contacting; wherein the tread is comprised of (1) 10 phr to 35 phr of high vinyl polybutadiene rubber having a glass transition temperature which is within the range of −40° C. to 10° C., (2) 65 phr to 90 phr of tin-coupled isoprene-butadiene rubber having a glass transition temperature which is within the range of −90° C.

Abstract: This invention relates to vulcanizable rubber compounds based on styrene-butadiene rubber, which contain a special vulcanizing system, which are reinforced with silica and which contain a filler activator, for tire treads which exhibit improved abrasion-resistance.

Abstract: Sets of fluid premixes useful for adhesives and caulks are provided. Also provided are methods of providing adhesive lines and a caulk lines using the sets of premixes. Further provided are ranges of adhesives and caulks based on the adhesive and caulk lines. Utilizing these methods the manufacturer, seller, or user can to adjust the adhesive or caulk at the point of manufacture, sale, or use to suit the processing and end-use conditions, in addition to the other benefits offered by delayed product differentiation.

Abstract: The invention concerns rubber compounds consisting of at least one double bond-containing rubber and additions of polybutadiene rubber particles having a glass transition temperature <−60° C. together with vulcanizates and rubber molding manufactured therefrom.

Abstract: The invention concerns a rubber sulfur-vulcanizable composition designed for manufacturing tire treads, comprising at least a diene elastomer, a white filler as reinforcing filler and as coupling agent (white filler/elastomer) a multifunctionalized polyorganosiloxane comprising per molecule: a) at least a first siloxyl unit bearing, on the silicon atom, at least one linear or branched C1-C15 alkoxyl radical; and b) at least a second siloxyl unit bearing, on the silicon atom, at least one radical of general formula Z—SH, Z being a linear or branched divalent hydracarbon, comprising preferebly 2 to 30 carbons.

Abstract: A rubber composition for a tire tread comprising (1) (i) 60 to 90 parts by weight of natural rubber and/or polyisoprene rubber, (ii) 10 to 35 parts by weight of a high cis polybutadiene rubber having a melt viscosity of 90 to 150 cps and a cis content of 90% by weight or more, and (iii) 0.5 to 5 parts by weight of an A-B type block copolymer composed of (A) a poly(styrene-butadiene) or polybutadiene block having a styrene content (St) of 0 to 35% by weight and a butadiene content (Bd) of 65 to 100% by weight, having a 1,2-vinyl bond content (Vn) of 5 to 80 mol %, and satisfying the relationship of Vn≦2St+30 and (B) a polyisoprene block having a cis content of at least 70% by weight, in a ratio by weight (A)/(B) of 20 to 80/80 to 20, and (2) 40 to 60 parts by weight of carbon black having an N2SA of 125 m2/g or more.

Abstract: The invention relates to a water-borne hybrid binder composition. It is obtained by mixing about 20-80% by weight of A), an aqueous dispersion of a polymer, said dispersion having a dry-solids content of at least 45% by weight, and containing at least 0.1% by weight of B) a single surfactant or a mixture of two or more different surfactants and protective colloids, and about 80-20% of C) one or more resins being emulsifiable in water and having a dry solids content above 90% by weight, by adding the resin C to the dispersion A under agitation, the resulting hybrid binder composition obtaining a dry-solids content of 60-95% by weight. The invention also relates to the use of the binder composition as a component in a paint or lacquer mixture.

Abstract: A thermoreversibly thickening binder composition, comprises a resin latex wherein the amount of an emulsifier in the aqueous phase is smaller than 0.01 mmol/g, and a vinyl polymer having reversibility of hydrophilicity and hydrophobicity at a certain transition temperature. The resin latex is preferably prepared by using an emulsifier having a radically polymerizable group, and preferable as said vinyl polymer is a polymer having a cation-forming group. The binder composition exhibits an excellent chemical stability to factors other than heat without causing migration of the latex resin particles onto the surface of the coated layer even during the time of heat-drying, and thermoreversible thickening effects caused by a sharp heat-sensitive gelling properties. When applied to preparation of coated paper and pressure-sensitive recording sheet, the binder composition provides products excellent in gloss, printability and color producing properties.

Abstract: A kneaded rubber for expandable formulation, such as a material for die forming. The polymer components in the kneaded rubber principally comprise a polymer alloy, further comprising a sea phase of a ethylene/&agr;-olefin/non-olefin/non-conjugated polyene terpolymer rubber and an island phase of a polyolefin resin. The polyolefin resin wholly or largely comprises a monomer C4-C6 &agr;-olefin and has an MFR of at least 15 g/10 min at 190° C. under a load of 2.196 kgf according to ASTMD 1238. The kneaded rubber satisfies the following Mooney viscosity profile formula according to JIS K 6300: (ML1+480° C.)−(ML1+4160° C.)≧15.

Abstract: The present invention provides a rubber composition and a pneumatic tire using the rubber composition. A rubber composition which comprises: a blend rubber of a copolymer and other diene base rubbers, the copolymer being obtained by copolymerization of 1,3-butadiene and an aromatic vinylmonomer using an organic lithium compound as an initiator, the glass transition point of the copolymer being −50° C. or more, and the blend rubber comprising the copolymer in an amount of 20 parts by weight or more and the other diene base rubbers in an amount of 80 parts by weight or less per 100 parts by weight of the blend rubber; silica filler in an amount of 10 to 80 parts by weight per 100 parts by weight of the blend rubber; carbon black in an amount of 20 to 80 parts by weight per 100 parts by weight of the blend rubber; and a specific silane coupling agent, i.e.

Abstract: Thermoplastic elastomers of high strength, high elasticity and good dyeability, the incorporated elastomeric particles of which have an average particle diameter of 0.05 to 5 &mgr;m, from propylene homopolymers and/or propylene copolymers, elastomeric C2 to C8 olefin copolymers and/or terpolymers and multifunctional, unsaturated monomers are formed by a method, for which mixtures of propylene homopolymers and/or propylene copolymers, elastomeric C2 to C8 olefin copolymers and/or terpolymers and readily volatile C4 to C7 dienes are reacted in the melt. The thermoplastic elastomers, as well as mixtures with conventional polyolefins, are suitable for use in the vehicle industry, in the domestic appliances industry, in the building sector and in medical technology.

Abstract: A rubber composition for solid golf balls comprising: (a) 50 to 100 parts by weight of a polybutadiene rubber with a 1,4-cis bond content of 80% or more, a 1,2-vinyl bond content of 2.0% or less, and a ratio (Mw/Mn) of the weight average molecular weight (Mw) and the number average molecular weight (Mn) of 3.5 or less, (b) 0 to 50 parts by weight of a diene-type rubber other than the component(a), provided that the total amount of the component (a) and component (b) is 100 parts by weight, (c) 10 to 50 parts by weight of a cross-linking monomer, (d) 20 to 80 part by weight of inorganic filler, and (e) an effective amount of an organic peroxide. The solid golf balls prepared from the rubber composition provide a good shot feeling, run a long distance, and exhibit superior durability.

Abstract: The present invention relates to low-cost, efficiently-manufactured, polymer-based products useful as roofing shingles and similar products. The inventive shingles are weatherproof, inexpensive to manufacture and durable, particularly as contrasted with conventional shingles in areas of the country subject to hail damage. The invention also includes a method of making such shingle products. In a preferred embodiment, products of this invention use rubber material as the polymer base in combination with specific types of polyolefins. The rubber material can be most efficiently provided by the use of crumb rubber particles from spent automobile tires and other recycled rubber debris which are readily available and of very low cost. The products will have an average life far greater than that of current commercial roofing shingles, which are made using fiberglass or asphalt.

Abstract: A rubbery adhesive composition wherein at least one adherend is a rubber composition including butadiene rubber as a rubber ingredient, characterized in that butadiene rubber is included as a rubber ingredient and 3˜20% by weight of the butadiene rubber is syndiotactic-1,2-polybutadiene. Thus, it is possible to enhance the strength of the rubbery adhesive composition itself to improve the adhesion property before and after vulcanization without damaging the adhesion property at the interface.

Abstract: The present invention includes processes and resulting structures for producing a modified polymer having interconnecting channels. The interconnecting channels act as controlled transmission passages through the polymer. A hydrophilic agent is blended into the polymer so that it is distributed within the polymer. In one embodiment, an activation material is blended into the polymer so that the activation material is distributed within the product. The product is solidified so that the hydrophilic agent forms passages in the product through which a desired composition is communicable to the activation material that is entrained within the product. The solidified product may be used to form a desired shaped article such as plug type inserts and liners for closed containers, or it may be formed into a film, sheet, bead or pellet.

Abstract: Radiation polymerizable vinylether-based compositions, and cured vinylether-based formulations having a predetermined balance of tack, peel and shear particularly suitable for use in pressure sensitive adhesives are described.

Abstract: A tire tread comprises a copolymer of butadiene with isoprene and/or styrene having a room temperature elasticity of between 5 and 35% at 22.degree. C., polybutadiene rubber and an aromatic oil selected from the group consisting of an aromatic oil, naphthenic oil, paraffinic oil, and a mixture thereof.

Abstract: A composition is disclosed that comprises at least one base polymer, at least one resin and optionally one or more additives such as a filler, colorant, among other additives. The disclosed composition can applied by spraying, immersion, brushing, rolling onto the adherent surface; caulking, among other methods of application.

Abstract: Provided is an automobile vibration-isolating rubber composition, characterized in that a rubber component comprises from 10 to 80% by weight of a polybutadiene rubber which is obtained through the polymerization using a rare-earth element catalyst and which has a cis content of 97% or more, and from 90 to 20% by weight of at least one type of a rubber selected from a natural rubber, a synthetic polyisoprene rubber and a polystyrene-butadiene copolymer rubber. The automobile vibration-isolating rubber obtained by vulcanizing the rubber composition of the present invention has a low dynamic factor compared to the conventional product, making it possible to decrease a room noise caused by a road noise.

Abstract: The invention provides a petroleum-based aliphatic resin having: a) a Ring and Ball (R&B) softening point in the range of about 75 to about 110.degree. C., b) a weight average molecular weight (Mw) of about 1000 to about 2600 Dalton, a z-average molecular weight (Mz) from about 1900 to about 5000 Dalton and an Mw/Mn below about 2.0, c) a level of aromatic protons below about 1.5% with respect to the total protons determined by .sup.1 H-NMR, and d) a mixed methylcyclohexane aniline cloud point (MMAP) of about 90.degree. C. or less. The resins according to the invention are characterized by a high amount of cyclic structures. Further disclosed is a method of independently controlling the R&B softening point and the molecular weight of an aliphatic resin composition during its preparation by polymerization of a petroleum-based feed, the method being characterized in that the amount of cyclic structures in the resins is increased.

Abstract: A high shock absorbing rubber composition comprises a cured blend of a conjugated diene rubber such as natural rubber or nitrile rubber with an EPDM rubber, and significant amounts of silica and optionally clay. The cured composition has low pendulum rebound properties of 20% or less, and is suitable for use as sport grips such as tennis rackets or golf grips, hand tools, lawn equipment, and the like.

Abstract: This invention relates to a tire tread compound that is easily processable which can be used to improve the treadwear, rolling resistance and traction characteristics of tires. The tire tread compounds of this invention are a blend of tin-coupled polybutadiene, high vinyl polybutadiene and natural rubber. This blend of low glass transition temperature rubber and high glass transition temperature rubber is surprisingly easy to process which makes the concept of this invention commercially feasible. Thus, the tire tread compounds of this invention can be utilized in making tires having greatly improved traction characteristics and treadwear without sacrificing rolling resistance. These improved properties may be due, in part, to better interaction and compatibility with carbon black and/or silica fillers. The polybutadiene in the blend can be asymmetrical tin-coupled to further improve the cold flow characteristics of the rubber blend.

Abstract: (i) A starting rubber (A) comprising a terminal-modified and/or coupled diene rubber and having an average glass transition temperature TgA (.degree. C.) is mixed with a specific amount of the reinforcing agent are mixed at a temperature of at least 135.degree. C., followed by adding a starting rubber (B) comprising a terminal unmodified diene rubber and having a specific average glass transition temperature TgB (.degree. C.), and the remaining reinforcing agent and a softening agent; (ii) a starting diene rubber (A') having a specific weight average molecular weight Mw(A') and average glass transition temperature TgA' (.degree. C.) is contacted with a reinforcing agent, followed by adding a starting diene rubber (B') having a specific weight average molecular weight Mw(B) and average glass transition temperature TgB' (.degree. C.

Abstract: An impact absorbing macadam comprises 10 to 75% (preferably 25 to 45%) of a particulate rubber having a particle size of up to 40 mm, 25 to 90% (preferably 45 to 65%) of an aggregate having a particle of up to 40 mm and from 5 to 9% of a polymer modified bituminous binder. Typically such a macadam has a void volume, interconnected or unconnected, of from 5 to 25%. The polymer which modifies the bituminous binder is preferably an unbranched styrene butadiene styrene block copolymer forming about 7% of the modified binder. The macadam is suitable as a base for sports pitches and athletic tracks without a rubber shock pad overlay.

Abstract: This invention relates to a tire tread compound that is easily processable which can be used to improve the treadwear, rolling resistance and traction characteristics of tires. The tire tread compounds of this invention are a blend of tin-coupled polybutadiene, high vinyl polybutadiene and natural rubber. This blend of low glass transition temperature rubber and high glass transition temperature rubber is surprisingly easy to process which makes the concept of this invention commercially feasible. Thus, the tire tread compounds of this invention can be utilized in making tires having greatly improved traction characteristics and treadwear without sacrificing rolling resistance. These improved properties may be due, in part, to better interaction and compatibility with carbon black and/or silica fillers. The polybutadiene in the blend can be asymmetrical tin-coupled to further improve the cold flow characteristics of the rubber blend.

Abstract: This invention relates to a tire tread compound that is easily processable which can be used to improve the treadwear, rolling resistance and traction characteristics of tires. The tire tread compounds of this invention are a blend of tin-coupled polybutadiene, high vinyl polybutadiene and natural rubber. This blend of low glass transition temperature rubber and high glass transition temperature rubber is surprisingly easy to process which makes the concept of this invention commercially feasible. Thus, the tire tread compounds of this invention can be utilized in making tires having greatly improved traction characteristics and treadwear without sacrificing rolling resistance. These improved properties may be due, in part, to better interaction and compatibility with carbon black and/or silica fillers. The polybutadiene in the blend can be asymmetrical tin-coupled to further improve the cold flow characteristics of the rubber blend.

Abstract: Composite pressure sensitive hydrophilic adhesive, permeable for water vapor and losing its adhesivness in contact with liquid water, is particularly suitable for temporary glueing to the body surface for medical purposes. The composite is a gelled mixture of: (a) a water swellable, water insoluble polymer, soluble in polar water-miscible solvents boiling at atmospheric pressure at temperatures higher than 100.degree. C. as well as in their mixtures with minor amounts of water, (b) a hydrophilic water swellable polymer, insoluble in water as well as in polar water-miscible solvents boiling at atmospheric pressure at temperatures higher than 100.degree. C., and (c) a polar water-miscible innocuous solvent boiling at atmospheric pressure at temperatures higher than 100.degree. C., if desired mixed with a minor amount of water.

Abstract: A rubber composition suitable for use in grips of articles such as golf clubs, tennis rackets, bicycles and tools, comprising (1) a rubber component containing an ethylene-propylene-diene rubber (EPDM), and (2) 5 to 100 parts by weight of a polyisobutylene having a viscosity average molecular weight of 6,000 to 50,000, which provides grips having good feeling of touch, good non-slipping properties in both fine and rainy weather, and giving a small feeling of impact to mis-shot of golf balls as compared with conventional grips.

Abstract: The invention relates to a tire with a tread which is quantitatively reinforced with silica where the tread is composed of three basic elastomers, namely, emulsion polymerization prepared styrene/butadiene rubber, cis 1,4-polybutadiene rubber and high vinyl polybutadiene rubber. Optionally, the basic elastomer composition can also contain a minor amount of cis 1,4-polyisoprene natural rubber.

Abstract: The invention relates to a tire with a tread which is reinforced with carbon black and precipitated silica where the tread rubbers are of a blend comprised of at least one diene-based elastomer and a styrene/alphamethylstyrene resin, as hereinafter described.

Abstract: The invention relates to a tire with a tread which is quantitatively reinforced with silica where the tread is composed of three basic elastomers, namely, solution polymerization prepared styrene/butadiene rubber, cis 1,4-polybutadiene rubber and high vinyl polybutadiene rubber. Optionally the basic elastomer composition can also contain a minor amount of cis 1,4-polyisoprene natural rubber.

Abstract: Improved polyvinylchloride-free compositions useful for wall and floor coverings comprise an optionally functionalized, ethylenically unsaturated block copolymer of monoalkenyl aromatic hydrocarbon and conjugated alkadiene, or selectively hydrogenated derivative thereof, an ethylene polymer, functionalized polyalkylene, polyisobutylene and particulate filler.

Abstract: An adhesive composition comprised of (A) a latex of 100 wt. parts of a carboxyl group-containing highly saturated nitrile-conjugated diene copolymer rubber, (B) 5-30 wt. parts of a resorcinol-formaldehyde resin, and (C) 2-10 wt. parts of an aromatic epoxy resin. A composite comprised of a nitrile group-containing highly saturated copolymer rubber and a fibrous material, which has been treated with the adhesive composition. This composite is useful for belts.

Abstract: A sulfur-vulcanizable rubber mixture for a tire tread includes at least one terpolymer with a conjugated diene, an aromatic vinyl compound, and a monoolefin monomer. At least one phenolic component selected from the group consisting of a phenolic resin and a precursor mixture, containing phenol and aldehyde, for a phenolic resin is also present. A reinforcing agent in the form of finely divided silica or a mixture of finely divided silica and carbon black is also added.

Abstract: A pressure sensitive adhesive of a mutually immiscible first elastomer (styrene-butadiene block copolymer) exhibiting a first glass transition temperature and a second elastomer (e.g., a styrene-isoprene-styrene block copolymer) exhibiting a second glass transition temperature greater than the first is tackified by a tackifying system comprising tackifier preferentially miscible with the second elastomer to provide a dynamic mechanical spectrum plot of tangent delta versus temperature in .degree.C. showing two separate and distinct glass transition temperature peaks. The mixture exhibits excellent processability and ambient and low temperature adhesive properties.

Abstract: A process for producing a rubber composition comprising (i) a total amount of 100 parts by weight of starting rubbers (A) and (B), including 30 to 90 parts by weight of the starting rubber (A) having a glass transition temperature (Tg) of -40.degree. to 10.degree. C. and 10 to 40 parts by weight of the starting rubber (B) which is viscoelastically incompatible with the starting rubber (A) and has a Tg of at least 20.degree. C. lower than the Tg of the starting rubber (A) and (ii) 60 to 100 parts by weight of a reinforcing agent, wherein the starting rubber (A) and at least 80% by weight of the total weight of the reinforcing agent are mixed in a hermetic type mixer at 130.degree. C. to 200.degree. C. for at least 10 seconds, then the starting rubber (B) and the remaining reinforcing agent are added and mixed.

Abstract: A composite pressure-sensitive hydrophilic adhesive such as for holding a medical or cosmetic treatment against the skin of a person is composed of a crosslinked polymer and a non-crosslinked polymer and a polar water-miscible solvent having a boiling point above 100.degree. C. at atmospheric pressure. The adhesive has little or no cold flow and can be applied in sheets. An alternate combination of polymers and a method of making both compositions is also disclosed.

Abstract: This invention relates to a tire having a tread composed of quantitatively silica reinforced rubber composition, with a minor amount, if any, of carbon black where the tread elastomers are primarily composed of coupled styrene/isoprene/butadiene terpolymer with tin or silicon in combination with selected diene-based elastomers.

Abstract: A pressure sensitive adhesive composition comprising a natural or synthetic rubber and a thermoplastic polyolefin blend comprising ethylene-propylene rubber, hydrogenated polyisoprene and polypropylene.

Abstract: Provided is an automobile vibration-isolating rubber composition, characterized in that a rubber component comprises from 10 to 80% by weight of a polybutadiene rubber which is obtained through the polymerization using a rare-earth element catalyst and which has a cis content of 97% or more, and from 90 to 20% by weight of at least one type of a rubber selected from a natural rubber, a synthetic polyisoprene rubber and a polystyrene-butadiene copolymer rubber. The automobile vibration-isolating rubber obtained by vulcanizing the rubber composition of the present invention has a low dynamic factor compared to the conventional product, making it possible to decrease automobile passenger compartment noise caused by road noise.

Abstract: A rubber composition for use in a tire tread comprises particular amounts of carbon black, silica, silane coupling agent and softening agent in addition to the specified diene rubber as a rubber ingredient and has specified storage modulus ratio after vulcanization and hystresis loss at 150% strain and provides pneumatic tires capable of stably developing the steering stability under wide-range service conditions of from low temperature to high temperature and from wet road surface to dry road surface.

Abstract: There is disclosed a method for adhering rubber to reinforcing materials which comprises embedding a textile fiber or metal reinforcing material in a vulcanizable rubber composition comprising rubber, a vulcanizing agent, reinforcement, a methylene donor, a methylene acceptor and a maleic anhydride functionalized triblock copolymer having polystyrene endblocks and poly-(ethylene/butylene) midblocks.

Abstract: There is disclosed a method for adhering rubber to reinforcing materials which comprises embedding a textile fiber or metal reinforcing material in a vulcanizable rubber composition comprising rubber, a vulcanizing agent, reinforcement, a methylene donor, a methylene acceptor and a maleic anhydride functionalized triblock copolymer having polystyrene endblocks and poly-(ethylene/butylene) midblocks.

Abstract: An elastic paving material includes a mixture of 90-50% by weight of fibrous rubber chips each having a length of 3-30 mm and a diameter of 0.3-3 mm, and 10-50% by weight of crushed pieces of golf balls having a particle size of 3-50 mesh. A curable liquid binder is added so as to bond the fibrous rubber chips and the crushed pieces of golf balls. Another elastic paving material includes only pieces of golf balls having a particle size of 3-50 mesh, and a curable liquid binder is added thereto so as to bond the pieces of golf balls. The crushed pieces of golf balls have a color different from that of the fibrous rubber chips, consist of particles having various colors, or are colored in advance.

Abstract: A low shear modulus vulcanizate for construction of flexible bearings, particularly for rocket motors, consisting essentially of a mixture of two natural or synthetic rubber copolymers, the first having about 92% cis-1,4-polyisoprene and about 8% trans-1,4-polyisoprene moieties and the second having about 98% by weight cis-1,4-polyisoprene and about 2% by weight trans-1,4-polyisoprene moieties. The composition is lightly filled and contains a low proportion of sulfur, so the vulcanizate has the required low shear modulus, low rate of thermal crystallization at low temperatures, and an acceptably high shear strength.

Abstract: Intervulcanized compositions having improved curing efficiency are prepared by the free radical curing of a mixture of an ethylenically unsaturated diolefin polymer such as natural or synthetic rubber and a saturated or low unsaturation polymer such as an ethylene propylene elastomers copolymer which contains functional groups pendant to the polymer chain. These functional groups contain an olefinic or vinyl double bond positioned alpha, beta to a substituent group which activates the double bond towards free radical addition reactions with the diolefin polymer. Preferred functionality includes benzylic ester functionality represented by the structure: ##STR1## wherein R.sub.2 and R.sub.3 are independently selected from hydrogen or C.sub.1 to C.sub.6 alkyl, and R.sub.4 is selected from hydrogen, C.sub.1 to C.sub.28 alkyl, aryl or C.sub.2 to C.sub.28 alkenyl.

Abstract: The present invention provides a rubber composition having high impact residence, preferred processability and workability which may be used for the manufacture of one-piece solid golf ball, solid core of multi-layered solid golf ball, solid center of thread-wound golf ball, etc. The rubber composition is characterized by that a rubber component is made from a mixture of:(1) 60 to 95 wt % of a polybutadiene containing at least more than 40% of cis-1,4 bond and having a Mooney viscosity [ML.sub.1+4 (100.degree. C.)] of 50 to 70, obtained by using lanthanum rare earth-based catalyst, nickel-based catalyst or cobalt-based catalyst, or a mixture thereof with another polybutadiene obtained by using a catalyst other than the above mentioned one, and(2) 5 to 40 wt % of a polyisoprene containing at least more than 90% of cis-1,4 bond and a Mooney viscosity of 70 to 90.

Abstract: A rubber composition having good physical properties such as breaking properties, wear strength and grip properties, and good processability at the same time is suitable for a high performance tire. A nitrogen containing polymer with a weight average molecular weight of 70.times.10.sup.4 to 250.times.10.sup.4 is compounded with 60 to 200 phr of carbon black, a softener comprising 30 to 250 phr of a process oil and/or 5 to 100 phr of liquid polymer, and not more than 60 parts of another polymer.

Abstract: A pneumatic tire for all seasons comprises a tread provided with a foamed rubber containing a given amount of a particular resin such as crystalline syndiotactic 1,2 -polybutadiene having specified hardness and average particle size, and having specified expansion ratio, average expanded cell size and storage modulus (E') at -20.degree. C. of a given range, and exhibits satisfactory braking and traction performances at not only dry-on-ice state but also wet-on-ice state while sufficiently holding the steering stability, durability and low fuel consumption in summer season.