Abstract: Natural rubber obtained by a deproteinizing treatment of a natural rubber latex and has a total nitrogen content adjusted in the range of 0.12 to 0.30% by weight and a rubber composition and a pneumatic tire using the natural rubber. The processability of natural rubber can be improved without adverse effects on the physical properties proper to natural rubber. The rubber composition exhibits an improved low hysteresis loss property and improved abrasion resistance and can be advantageously used for the tire case members and the tire tread of pneumatic tires.

Abstract: The invention relates to a sulfur-vulcanizable rubber compound, in particular for treads of tires, which contains at least one diene rubber, liquid polybutadiene with a molecular weight of 1500-10000 g/mol and a vinyl content of 15-50%, at least one polar filler, at least one high-structure black with an iodine adsorption number of 115-200 g/kg and a DBP number of 125-160 mL/100 g and at least one glyceride and/or one factice for good abrasion characteristics, good wet traction and good traction on ice and snow with good dry braking at the same time.

Abstract: This invention relates to a latex polymer that when used in adhesive formulations exhibits a favorable level of peel and shear balance as well as a resistance to water whitening.

Abstract: The invention relates to a sulphur-vulcanizable rubber compound for the production of tread rubbers for tires, which contains at least one diene rubber, at least one silane coupling agent, at least one filler interacting with the silane coupling agent and further conventional additives. For a reduced loss factor tan at 55° C.

Abstract: This invention relates to a rubber modified acrylic and/or vinyl resin comprising the mini-emulsion polymerization product of at least one rubber compound substantially dissolved in at least one acrylic monomer and/or vinyl monomer.

Abstract: An elastomeric composition usable for the manufacture of tires, based on at least (i) a diene elastomer, (ii) an inorganic filler as reinforcing filler and (iii), as (inorganic filler/diene elastomer) coupling agent, a polysilylated organosilicon compound which is at least bifunctional and can be grafted onto the elastomer by means of a sulfur group having a polythiosulfenamide function, of formula: ?Si—A—Sx—NR1R2 ,??(I) in which: A is a divalent bond group, whether straight-chain or branched, which makes it possible to join the polythiosulfenamide group to a first silicon atom of the organosilicon compound; x is an integer or fractional number of from 2 to 4; R1 represents hydrogen, a monovalent hydrocarbon group, or R2; and R2 represents the grouping: —B—Si?, in which: B is a divalent bond group, whether straight-chain or branched; Si represents a second silicon atom of the organosilicon compound. The invention also concerns tires and tire treads comprising a composition of this type.

Abstract: Disclosed is a rubber composition for tires. More particularly, the present invention provides a rubber composition for tires which contains surface treated staple fibers and a metal soap, a rubber including the above rubber composition and a tire comprising the rubber including the above rubber composition. In an aspect of the present invention, a preferred embodiment of the present invention comprises a rubber composition for tires which contains surface treated staple fibers and a metal soap. Another aspect of the present invention includes a rubber including the above rubber composition for tires. The present invention also provides a tire product comprising the rubber including the above rubber composition for tires.

Abstract: Vulcanizable elastomeric compositions and vulcanizates are prepared by employing a strong acid. The strong acid is believed to enhance the reaction between a silica particle and a silica-reactive compound.

Abstract: A rubber material for wiper blades of windshield wipers or for motor vehicle tires, is disclosed that contains a copolymer based on isoprene and at least one other polymerizable monomer.

Abstract: A rubber composition includes at least one rubber component selected from the group consisting of natural rubbers and synthetic rubbers, a graphitized carbon material, and a polycyclic aromatic compound having a crosslinking group. The graphitized carbon material is preferably vapor-grown carbon fiber. The content of the graphitized carbon material is preferably 0.1 to 100 parts by mass based on 100 parts by mass of the rubber component.

Abstract: A sulphur-vulcanizable rubber composition usable for the manufacture of tires, based on at least: (A)—one diene elastomer selected from the group consisting of polybutadienes, natural rubber, synthetic polyisoprenes, butadiene copolymers, isoprene copolymers and mixtures of these elastomers (component A); (B)—a reinforcing white filler (component B); (C)—a coupling agent (white filler/diene elastomer) bearing at least one activated double ethylene bond (component C), with which there is associated: (D)—between 0.05 and 1 phr (parts by weight per hundred of elastomer) of a heat-triggered radical initiator (component D). The coupling agent is in particular an alkoxysilane of the family of alkoxy(C1–C4)-silylpropyls, in particular a trialkoxy(C1–C4)-silylpropyl methacrylate, in particular trimethoxy-silylpropyl methacrylate. Process for preparing such a rubber composition. Tire or semi-finished product, in particular tread, for a tire comprising a rubber composition according to the invention.

Abstract: A rubber composition usable for the manufacture of tires, based on at least one diene elastomer, a reinforcing inorganic filler and a coupling agent providing the bond between the inorganic filler and the elastomer, wherein said inorganic filler comprises a silicon carbide having the following characteristics: (a) a BET specific surface area of between 20 and 200 m2/g; (b) an average particle size (by mass), dW, of between 10 and 350 nm. Tires or semi-finished products for tires such as treads comprising said rubber composition.

Abstract: A tire tread comprising a rubber composition based on (phr: parts by weight per hundred parts of elastomer): (i) a diene elastomer; (ii) more than 50 phr of an inorganic filler as reinforcing filler; (iii) between 2 and 15 phr of an (inorganic filler/diene elastomer) coupling agent; (iv) between 1 and 10 phr of a methylene acceptor, and (v) between 0.5 and 5 phr of a methylene donor. This tread has, after mechanical running-in of the tire for which it is intended (“auto-accommodation”), a rigidity gradient which increases radially from the surface towards the inside of the tread. Use of such a tread for the manufacturing or recapping of tires. Tires comprising a tread according to the invention, in particular of the snow or ice type (“winter” tires).

Abstract: The present invention relates to a sulfur-cross-linkable elastomeric composition that is useful for the manufacture of tires. This elastomeric composition is based on at least one isoprene elastomer (in particular natural rubber), a reinforcing inorganic filler (in particular, silica), and an (inorganic filler/isoprene elastomer) coupling agent. The coupling agent is a multifunctional polyorganosiloxane (POS), which comprises functions denoted as “Y” and “X”, wherein the Y function is at least one hydroxyl or hydrolyzable function grafted to the silicon atoms of the coupling agent and the X function is a group bearing at least one activated ethylene double bond and is grafted to the silicon atoms of the coupling agent. This POS is, in particular, a POS having an imide, acid or ester function, the ethylene double bond of which is activated by at least one adjacent carbonyl group (—C?O).

Abstract: The present invention provides a deproteinized natural rubber latex wherein coagulation of a rubber component does not occur when the concentration of calcium ions (Ca2+) is 0.01 mol/L or less and coagulation of the rubber component occurs when the concentration of Ca2+ is 0.1 mol/L or more; a method of preparing the deproteinized natural rubber latex, which comprises adding a protease and two or more surfactants having different coagulation properties to calcium ions (Ca2+) to a natural rubber latex and maturing the natural rubber latex; a rubber product using the deproteinized natural rubber latex; and a proteolytic agent comprising a protease and two or more surfactants.

Abstract: This invention relates to a resin composition useful as a vibration-damping agent and the like. The resin composition is formulated by adding 1 wt % or more of styrenated phenol obtained by the reaction of a phenol with styrene to a polycyclic aromatic oligomer obtained by condensing a polycyclic aromatic compound containing 2 to 3 rings and formaldehyde. The polycyclic aromatic oligomer is obtained by the reaction of a polycyclic aromatic compound with formaldehyde and, if necessary, further with a phenol in the presence of an acid catalyst and has a number average molecular weight of 300–1000. The styrenated phenol is obtained by the reaction of 1 mole of a phenol with 1–2.5 moles of styrene in the presence of an acid catalyst.

Abstract: Insulation for a rocket motor is provided, as is a method for insulating a rocket motor. The insulation includes a cured elastomer and vapor-grown carbon fibers dispersed in the cured elastomer. The cured elastomer is preferably formed from a precursor composition comprising an EPDM terpolymer. Generally, the vapor-grown carbon fibers have an internal graphitized tube surrounded by a sheath of vapor-deposited amorphous carbon.

Abstract: The present invention relates to a resin composition comprising a resin and apatite, wherein referring to the particulate form of said apatite present in the resin composition thus obtained, the apatite is present in a particulate form having an average diameter or average thickness (d) of not greater than 100 nm and an average aspect ratio (L/D) of not smaller than 5 as defined by the ratio of the average length (L) to said average diameter or average thickness (d).

Abstract: The present invention provides a deproteinized natural rubber latex wherein coagulation of a rubber component does not occur when the concentration of calcium ions (Ca2+) is 0.01 mol/L or less and coagulation of the rubber component occurs when the concentration of Ca2+ is 0.1 mol/L or more; a method of preparing the deproteinized natural rubber latex, which comprises adding a protease and two or more surfactants having different coagulation properties to calcium ions (Ca2+) to a natural rubber latex and maturing the natural rubber latex; a rubber product using the deproteinized natural rubber latex; and a proteolytic agent comprising a protease and two or more surfactants.

Abstract: A method for reducing allergenicity of natural latex rubber. The natural latex rubber, prior to its vulcanization, is admixed with mineral oil and extracted to reduce protein levels therein. Ideally, the mineral oil is characterized as having a density of approximately 0.818 to 0.880 and a viscosity of approximately 33.5 cf at 40° C.

Abstract: The present invention relates to tires suitable for bearing heavy loads, and to the use of a rubber composition to form the treads of such tires which delays the appearance of irregular wear on the treads of such tires during travel. The invention applies to tires for motor vehicles, such as heavy vehicles, construction vehicles or aircraft. The rubber composition comprises: an elastomeric matrix comprising majoritarily at least one diene elastomer having at one or more of its chain ends a functional group which is active for coupling to a reinforcing white filler, a reinforcing filler comprising at least 50% by weight a reinforcing white filler, and a reinforcing white filler/functionalized diene elastomer bonding agent. The present invention relates to tires suitable for bearing heavy loads, and to the use of the rubber composition to delay the appearance of irregular wear on the treads of such tires during travel.

Abstract: The present invention relates to tires suitable for bearing heavy loads, and to the use of a rubber composition to form the treads of such tires which delays the appearance of irregular wear on the treads of such tires during travel. The invention applies to tires for motor vehicles, such as heavy vehicles, construction vehicles or aircraft. The rubber composition comprises: an elastomeric matrix comprising majoritarily at least one diene elastomer having at one or more of its chain ends a functional group which is active for coupling to a reinforcing white filler, a reinforcing filler comprising at least 50% by weight a reinforcing white filler, and a reinforcing white filler/functionalized diene elastomer bonding agent. The present invention relates to tires suitable for bearing heavy loads, and to the use of the rubber composition to delay the appearance of irregular wear on the treads of such tires during travel.

Abstract: This invention relates to an UV stabilizing additive composition comprising an ortho-hydroxy triazine compound, a hindered hydroxybenzoate compound and optionally a hindered amine compound. This additive composition may be used to stabilize materials from UV radiation. This invention also contemplates a method of stabilizing a material by contacting the material with the UV stabilizing additive composition.

Abstract: The natural rubber master batch of the present invention is prepared by mixing a natural rubber latex having its amide linkages cleaved and an aqueous slurry having a filler dispersed in water. Alternatively, the natural rubber master batch is prepared by a method including a step for mixing a natural rubber latex and an aqueous slurry containing dispersed fillers having a specific particle size distribution and a limited range of 24M4DBP absorption. The natural rubber composition of the present invention is prepared by compounding natural rubber, which contains non-rubber components prepared by cleaving amide linkages of natural rubber latex, with silica and/or a particular inorganic filler.

Abstract: A rubber-based pressure-sensitive adhesive composition comprising a rubbery polymer, and a natural rubber having a weight-average molecular weight of from 100,000 to 400,000, wherein the amount of the natural rubber is 5 parts by weight or more and less than 100 parts by weight, based on 100 parts by weight of the rubbery polymer.

Abstract: A vulcanizable rubber composition comprises (a) a rubber component; (b) a methylene donor compound; and (c) a methylene acceptor comprising a blend of a high ortho-ortho bonded phenolic novolak resin and a resorcinolic resin. The resin blend can be made by a number of methods. For example, it can be prepared by first reacting one or more phenolic compounds represented by the following formula: where R is selected from the group consisting of H, an alkyl group chain of 1-16 carbon atoms and an aralkyl group of 8-12 carbon atoms with an aldehyde in the presence of an ortho directing catalyst and then combining a resorcinol-formaldehyde novolak resin to obtain a phenolic and resorcinolic novolak resin blend.

Abstract: Modified silica fillers are prepared by contacting silica with blends or mixtures containing diorganodihalosilanes and tetrahalosilanes in weight ratios of 1:0.1 to 1:2, respectively. While dialkyldichlorosilanes and tetrahalosilanes such as dimethyldichlorosilane and silicon tetrachloride, respectively, are most preferred, the blends or mixtures may also comprise compositions containing other silanes such as mercaptopropyltriethoxysilane.

Abstract: This invention relates to preparation and use of a rubber/carbon black composite comprised of at least one elastomer which contains a dispersion therein of carbon black aggregates. Such carbon black is formed by preparing a pre-blend comprised of uncompacted carbon black aggregates and oil and/or aqueous latex of, preferably, a low molecular weight diene-based elastomer particles, followed by blending said pre-blend with an aqueous emulsion of diene-based elastomer particles and/or with an organic solution of a diene-based elastomer, and/or with solid diene-based elastomers, and recovery therefrom of a solid rubber/carbon black composite comprised of said diene-based elastomer, (which may include butyl rubber, EPDM rubber and thermoplastic polymers), which contains a dispersion therein of said carbon black aggregates having an apparent density significantly lower than the specific gravity of said carbon black aggregates and significantly lower than compacted carbon black aggregates.

Abstract: Elastomers which have excellent stability to prevent oxidative, thermal, dynamic, light-induced and/or ozone-induced degradation comprise, as stabilizers, at least one compound of the formula (I): [R—S(═O)m—CH2—CH(OH)—CH2]n—N(R1)2−n—R2, in which R is C4-C20alkyl, hydroxyl-substituted C4-C20alkyl; phenyl, benzyl, &agr;-methylbenzyl, &agr;,&agr;-dimethylbenzyl, cyclohexyl or —(CH2)qCOOR3, and, if m is 0, R may additionally be (a); and, if n is 1 and R4 is hydrogen, R may additionally be R2—R1N—CH2—CH(OH)—CH2—S(═O)m—(CH2)x— or R2—R1N—CH2—CH(OH)—CH2—S(═O)m—CH2—CH2—(OCH2—CH2)y—, R1 is hydrogen, cyclohexyl or C3-C12alkyl, R2 is (b), R3 is C1-C18alkyl, R4 is hydrogen or —CH2—CH(OH)—CH2—S(═O)m—R, X is C1-C8alkyl, Y is C1-C8alkyl, m is 0 or 1, n is 1 or 2, q is 1 or 2, x is from 2 to 6, and y is 1 or 2.

Abstract: A coupler is described for use in carbon black filled rubber compositions. The coupler includes an amine group and a thiol group or a polysulfidic linkage. The coupler improves the interaction of the carbon black with the rubber as measured by a decrease in the tan delta at 60° C. while substantially maintaining the tan delta at 0° C.

Abstract: A black rubber sidewall compound essentially free of a silanated rubber which includes a combination of less than 10 phr of a rosin acid type “tackifier” and less than 1 phr of a t-alkanolamine generates, upon curing against a metal mold surface having a finish in the range from about 8 RA to 32 RA, a reaction product which, at the surface of the sidewall, has a gloss in the range from about 10 to 40 lasting at least one month. A secondary advantage is that the surface of the mold remains clean enough not to require refurbishing through at least 20% more curing cycles than is possible with a sidewall conventional sidewall compound without the specified tackifier and t-alkanolamine. Multiple washing of the sidewalls during a month of using the tire, fails to diminish the gloss substantially.

Abstract: A vulcanizable rubber composition comprises (a) a rubber component; (b) a methylene donor compound; and (c) a methylene acceptor comprising a blend of a high ortho-ortho bonded phenolic novolak resin and a resorcinolic resin. The resin blend can be made by a number of methods.

Abstract: There is disclosed a rubber composition comprising:

Abstract: Provided are a viscosity stabilizer comprising carbon black and/or silica and further blended with at least one selected from the group consisting of a plasticizer, a processing aid, a softening agent and a dispersant, a viscosity-stabilized natural rubber composition blended with the viscosity stabilizer described above in an amount of 5 to 80 parts by weight per 100 parts by weight of natural rubber, a process for producing a viscosity-stabilized natural rubber composition, which comprises adding the viscosity stabilizer described above to natural rubber in producing a natural rubber master batch, and a method of controlling a rise in the viscosity of natural rubber, which comprises adding the viscosity stabilizer described above to natural rubber in producing a natural rubber master batch.

Abstract: A fine-particle, free-flowing rubber powder containing silicatic fillers, one or more organosilanes having trialkoxysilyl groups, and a rubber prepared by solution polymerization is prepared by a process that starts from a two-phase system: 1) filler in water, and 2) rubber in organic solvent. A rubber/silicatic filler/silane composite is formed during transfer, under gentle conditions, of the various reactants into a single phase. The process features a high degree of freedom in selecting forms of filler and in selecting the organosilane and gives a finished rubber powder in which a silicatic filler and an organosilane have undergone complete chemical reaction.

Abstract: The present invention relates to (1) a deproteinizing agent for natural rubber latex, comprising a protease and one or more water-soluble polymers as an active component; (2) a deproteinized natural rubber latex, which is prepared by subjecting to a deprotenization treatment using the deproteinizing agent, and a method of producing the same; (3) a method of producing a rubber product, which comprises incorporating at least a vulcanizing agent into the latex (2), dipping a mold in the resulting compound latex, and vulcanizing and drying a rubber film formed on the mold; and (4) a method of producing a rubber product, which comprises incorporating at least a heat sensitizer and a vulcanizing agent into the latex (2), dipping a mold in the resulting heat-sensitive coagulable compound latex, and vulcanizing and drying a rubber film formed on the mold.

Abstract: A method for reducing allergenicity of natural latex rubber. The natural latex rubber, prior to its vulcanization, is admixed with mineral oil and extracted to reduce protein levels therein. Ideally, the mineral oil is characterized as having a density of approximately 0.818 to 0.880 and a viscosity of approximately 33.5 cf at 40° C.

Abstract: Mixture of at least one filler and organosilicon compounds of the general formula Y—Sx-Z, wherein the filler is surface-treated, hydrophobic, precipitated silica, are prepared by homogeneously applying an organosilicon compound from a nozzle to the surface-treated, hydrophobic, precipitated silica in a mixing unit at a temperature of less than 50° C. The mixture can be used in rubber mixtures.

Abstract: This invention relates to preparation and use of a rubber/carbon black composite comprised of at least one elastomer which contains a dispersion therein of carbon black aggregates. Such carbon black is formed by preparing a pre-blend comprised of uncompacted carbon black aggregates and oil and/or aqueous latex of, preferably, a low molecular weight diene-based elastomer particles, followed by blending said pre-blend with an aqueous emulsion of diene-based elastomer particles and/or with an organic solution of a diene-based elastomer, and/or with solid diene-based elastomers, and recovery therefrom of a solid rubber/carbon black composite comprised of said diene-based elastomer, (which may include butyl rubber, EPDM rubber and thermoplastic polymers), which contains a dispersion therein of said carbon black aggregates having an apparent density significantly lower than the specific gravity of said carbon black aggregates and significantly lower than compacted carbon black aggregates.

Abstract: The present invention relates to tires suitable for bearing heavy loads, and to the use of a rubber composition to form the treads of such tires which delays the appearance of irregular wear on the treads of such tires during travel. The invention applies to tires for motor vehicles, such as heavy vehicles, construction vehicles or aircraft.

Abstract: The invention concerns a process for concentrating polymer latexes, which can be separated into a latex phase and a serum phase in a separator with the aid of an auxiliary coalescing device.

Abstract: A pneumatic tire having a tread comprised of (a) a diene-based elastomer containing olefinic unsaturation and (b) from 1 to 150 phr of a metal oxide aerogel.

Abstract: A rubber composition having improved properties containing a starting rubber (e.g., diene rubber) and a polysiloxane having the following alkoxysilyl group (I) and/or acyloxysilyl group (II) and having an average degree of polymerization of 3 to 10,000: ≡Si—OR1  (I) ≡Si—OCOR2  (II) wherein, R1 is a substituted or unsubstituted monovalent hydrocarbon group having 1 to 18 carbon atoms or an organic group containing an ether bond and R2 is hydrogen or a hydrocarbon group having 1 to 21 carbon atoms.

Abstract: A rubber-based pressure-sensitive adhesive which (i) contains as the main rubber component a natural rubber comprising, as the main component, fine particles having a particle diameter of 1 &mgr;m or smaller contained in a raw natural rubber latex, (ii) contains as the main rubber component a linear natural rubber polymer contained in a raw natural rubber latex, (iii) contains as the main rubber component a natural rubber having a weight-average molecular weight of from 100,000 to 1,000,000 contained in a raw natural rubber latex, (iv) contains as the main rubber component a natural rubber having a rupture strength of 0.

Abstract: Disclosed is a cationic graft-modified natural rubber latex, which is obtained by cationically modifying the graft-natural natural rubber latex with a cationic surfactant in the presence of a nonionic surfactant such as polyoxyalkylene alkyl phenyl ether, polyoxyalkylene monostyryl phenyl ether, polyoxyalkylene distyryl phenyl ether or polyoxyalkylene tristyryl phenyl ether, the obtained rubber latex being useful as an adhesive for fibers and papers.

Abstract: Processes for preparing a carbon black product having an organic group attached to the carbon black. In one process at least one diazonium salt reacts with a carbon black in the absence of an externally applied electric current sufficient to reduce the diazonium salt. In another process at least one diazonium salt reacts with a carbon black in a protic reaction medium. Carbon black products which may be prepared according to process of the invention are described as well as uses of such carbon black products in plastic compositions, rubber compositions, paper compositions, and textile compositions.

Abstract: Disclosed are a cationic deproteinized natural rubber latex, in which rubber particles are positively charged and the concentration of said rubber particles is from 40 to 65% by weight and that the viscosity at 25° C. of said latex is 200 mPa·s or less, a method of preparing said latex which comprises subjecting to a deprotenization treatment using a proteolytic enzyme and a deproteinizing agent made of one or more surfactant selected from cationic and nonionic surfactants, and optionally adding a post additive comprising a cationic or nonionic surfactant as an active component, thereby to enable both surfactants described above to coexist, and a treating agent used in the same.

Abstract: The present invention relates to rubber compositions containing an elastomer and a trivalent phosphorous compound-silica complex.

Abstract: A method of reducing allergenicity of latex rubber products such as latex rubber gloves. The latex rubber product is treated with first bath of an alkane hydrocarbon followed by a protein substituting material in the form of a synthetic plasticizer. A final wash is carried out using an alkaline or oxidative wash to remove surface and interstice dwelling protein.

Abstract: A process for producing a natural rubber for a pressure-sensitive adhesive, which comprises decreasing a molecular weight of an unmasticated natural rubber by the action of a peptizing agent while dissolving the unmasticated natural rubber in an organic solvent, and a natural rubber-based pressure-sensitive adhesive composition comprising a natural rubber having a weigh average molecular weight Mw of 700,000 or less obtained by the process.