Abstract: Rubber composition for a tread, which enables not only improving handling stability, abrasion resistance, and fuel economy in a balanced manner, but also improving wet grip performance and processability in a balanced manner, in a pneumatic tire formed from the rubber composition. The rubber composition comprises a terminally-modified solution-polymerized styrene-butadiene rubber, a butadiene rubber synthesized in the presence of a rare earth catalyst, and a particular type of reinforcing agent.

Abstract: The present invention provides a method for synthesizing a polybutadiene more efficiently and stably which is possible to obtain a rubber composition and a tire excellent in durability (fracture resistance, wear resistance and crack growth resistance). A method for producing a polybutadiene, where a butadiene monomer is polymerized with the existence of rare-earth element compounds represented by the following formula (i): M-(NQ)1(NQ)2(NQ)3??(i) (in the formula, M is at least one selected from lanthanides, scandium and yttrium; (NQ)1, (NQ)2 and (NQ)3 are amide groups which may be the same or different to each other, and have M-N bonds).

Abstract: A process for preparing a polydiene, the process comprising the step of: polymerizing conjugated diene monomer in the presence of a (hydrocarbyloxyhydrocarbyl)amine, where said step of polymerizing employs a lanthanide-based catalyst system.

Abstract: The invention relates to a high-molecular-weight, linear, neodymium-catalysed polybutadiene having a high proportion, >95%, of cis-1,4 units having a low proportion, <1%, of 1,2-vinyl content, and also having a small molar-mass-polydispersity index (MPI), characterized in that Mooney viscosity (ML1+4 100° C.) of the polybutadiene is from 70 to 90 and The molar-mass-polydispersity index of the polybutadiene is smaller than 10.

Abstract: An activated preformed catalytic system for the 1,4-cis stereospecific polymerization of conjugated dienes based on at least: one or more preformation conjugated diene monomers, one or more salts of one or more rare-earth metals of one or more acids chosen from an organic phosphoric acid and an organic carboxylic acid, and a mixture thereof, one or more alkylating agents consisting of one or more alkylaluminiums of formula AlR3 or HAlR2, in which R represents an alkyl radical and H represents a hydrogen atom, one or more halogen donors consisting of an alkylaluminium halide, and one or more compounds corresponding to formula (I) below:

Abstract: The invention provides a polymer prepared from a substituted 1,3-butadiene (such as neophytadiene) derived from a plant of the Nicotiana species. The invention also provides smoking articles and smokeless tobacco compositions that include the polymers described herein. Further, the invention provides a method of polymerizing a substituted 1,3-butadiene derived from a plant of the Nicotiana species, the method including reacting a substituted 1,3-butadiene derived from a plant of the Nicotiana species with one or more reagents selected from the group consisting of an anionic initiator, a radical initiator, and a Ziegler-Natta catalyst.

Abstract: In general the present invention provides a process for forming conjugated diene polymer, the process comprising the step of polymerizing conjugated diene monomer in the presence of a catalytically effective amount of a catalyst composition formed by combining (a) a nickel-containing compound, (b) an alkylating agent, (c) a fluorine-containing compound, (d) a carboxylic acid, and (e) an alcohol.

Abstract: The invention relates to a high-molecular-weight, linear, neodymium-catalysed polybutadiene having a high proportion, >95%, of cis-1,4 units having a low proportion, <1%, of 1,2-vinyl content, and also having a small molar-mass-polydispersity index (MPI), characterized in that Mooney viscosity (ML1+4 100° C.) of the polybutadiene is from 70 to 90 and The molar-mass-polydispersity index of the polybutadiene is smaller than 10.

Abstract: Some embodiments of the invention include a process for separating rubber, resin and bagasse from at least a portion of a rubber producing plant including the steps of providing a plant portion and at least partially homogenizing the plant portion in the presence of a resin-solubilizing medium, and extracting rubber using a rubber solubilizing solvent. In some embodiments, the plant portion can include an antioxidant, that in some embodiments, the includes a substantially non-staining antioxidant. Some other embodiments include a process for separating rubber, resin and bagasse from a rubber producing plant comprising the steps of providing a plant portion and applying at least one antioxidant to at least a fraction of the plant portion, milling the plant portion with a milling solvent, and separating rubber form resin using phase separation fractionation. Some embodiments include separation of bagasse and resin components and one or more solvent recovery steps.

Abstract: The invention relates to a tire having a component composed of a composite of rubber chafer and outer sidewall layer components comprised of rubber compositions containing the same or different specialized cis 1,4-polybutadiene elastomers.

Abstract: A macromolecule includes at least one polymer chain and terminal functionality. The terminal functionality includes a ring-opened radical of a cyclosilazane or cyclic hydrosiloxane. The polymer can include unsaturated mer units and can be provided via anionic polymerization techniques. The macromolecule can be used as a component of a composition that also includes particulate fillers, with the composition being useful for the production of vulcanizates.

Abstract: Disclosed are a polybutadiene having a controlled microstructure, a narrow molecular weight distribution, minimal gel content, and a low APHA color, a modified polybutadiene, producing methods for both, and a rubber-reinforced styrene resin composition using the same. The polybutadiene of the present invention is characterized in that the ratio (Tcp/ML1+4) of a 5% toluene melting viscosity (Tcp) measured at 25° C. and the Mooney viscosity (ML1+4) at 100° C. is 2.0 or higher, the molecular weight distribution (Mw/Mn) is 2.80 or less, the gel content is 0.06 wt % or less, and the APHA color is 20 or less.

Abstract: A process for making a substantially saturated dendritic hydrocarbon polymer. The process has the following steps: (a) polymerizing an amount of a first alkadiene monomer under anionic conditions in the presence of a first organic monolithium initiator to produce a linear polyalkadiene having a lithiated chain end; (b) reacting the linear polyalkadiene with an amount of a second organic monolithium initiator in the presence of tetramethylethylene diamine to form a multilithiated polyalkadiene; (c) reacting the multilithiated polyalkadiene with an amount of a second alkadiene monomer to form a branched polyalkadiene; (d) repeating steps (b) and (c) with the branched polyalkadiene one or more times to prepare a dendritic polyalkadiene; and (e) hydrogenating the dendritic polyalkadiene to form the substantially saturated dendritic hydrocarbon polymer.

Abstract: A method for preparing a functionalized polymer, the method comprising the steps of (i) polymerizing conjugated diene monomer by employing a lanthanide-based catalyst to form a reactive polymer, and (ii) reacting the reactive polymer with a protected oxime compound.

Abstract: The invention relates to a high-molecular-weight, linear, neodymium-catalysed polybutadiene having a high proportion, >95%, of cis-1,4 units having a low proportion, <1%, of 1,2-vinyl content, and also having a small molar-mass-polydispersity index (MPI), characterized in that Mooney viscosity (ML1+4100° C.) of the polybutadiene is from 70 to 90 and The molar-mass-polydispersity index of the polybutadiene is smaller than 10.

Abstract: The invention relates to a high molecular weight bimodal neodymium-catalysed polybutadiene having a high proportion, >95%, of cis-1,4 units and a low proportion, <1%, of 1,2-vinyl content, wherein the polybutadiene has a linear polymeric main fraction and a long chain branched polymeric fraction, wherein the slope in the RGM relationship is >0.5 for the polymeric main fraction and <0.3 for the long chain branched polymeric fraction.

Abstract: This invention relates to a silica reinforcement-containing rubber composition which contains a functionalized polybutadiene rubber to promote a relatively low hysteretic loss to thereby enhance its desirability for tire sidewall and subtread applications in a sense of advantageously promoting reduced tire rolling resistance without significantly compromising various other desirable tire performance parameters.

Abstract: An isoprene or butadiene cis 1,4-selective polymerization catalyst system together with its polymerization method is provided. This catalyst system is composed of NCN-imine pincer type rare earth metal complex of formula [2,6-(CH?N—R1)2-4-R2-1-C6H2]LnX2(THF)n and alkylating reagent. In an hydrocarbon solvent or under bulk conditions, at a polymerization temperature in a range of ?20-120° C., the conjugated diene is polymerized by using the catalyst system, to produce polyisoprene and polybutadiene having controllable number-average molecular weight, molecular weight distribution of 3.0 or less than, and cis 1,4-content of 95% or more, even 99% or more. The crude rubber and vulcanized rubber of the polyisoprene have high strength, stretching crystallization capability and transparency.

Abstract: In general the present invention provides a process for forming conjugated diene polymer, the process comprising the step of polymerizing conjugated diene monomer in the presence of a catalytically effective amount of a catalyst composition formed by combining (a) a nickel-containing compound, (b) an alkylating agent, (c) a fluorine-containing compound, (d) a carboxylic acid, and (e) an alcohol.

Abstract: Disclosed are a polybutadiene having a controlled microstructure, a narrow molecular weight distribution, minimal gel content, and a low APHA color, a modified polybutadiene, producing methods for both, and a rubber-reinforced styrene resin composition using the same. The polybutadiene of the present invention is characterised in that the ratio (Tcp/ML1+4) of a 5% toluene melting viscosity (Tcp) measured at 25° C. and the Mooney viscosity (ML1+4) at 100° C. is 2.0 or higher, the molecular weight distribution (Mw/Mn) is 2.80 or less, the gel content is 0.06 wt % or less, and the APHA color is 20 or less.

Abstract: Disclosed is a process for producing a conjugated diene polymer having a very high content of cis-1,4 structures by using an yttrium compound-containing catalyst that is relatively easy to handle and has a high activity. Specifically disclosed is a process for producing a conjugated diene polymer containing cis-1,4 structures at a ratio of 99% or higher, which is characterized by polymerizing a conjugated diene in the presence of a catalyst produced from (A) a specific yttrium compound, (B) an ionic compound consisting of a non-coordinating anion and a cation, and (C) an organoaluminum compound.

Abstract: A rubber composition for tire sidewall which comprises a rubber component, which comprises polybutadiene rubber having a content of the cis-1,4-bond of 92% or greater and a content of the vinyl bond of 1.5% or smaller and natural rubber and/or at least one other diene-based synthetic rubber, and 10 to 70 parts by mass of carbon black having a specific surface area by nitrogen adsorption of 20 to 100 m2/g per 100 parts by mass of the rubber component and does not comprise a softener having an aniline point of 50° C. or lower and a tire using the rubber composition for sidewall. Excellent resistance to cut growth is obtained while sufficient workability is surely exhibited.

Abstract: The invention relates to a high-molecular-weight, linear, neodymium-catalysed polybutadiene having a high proportion, >95%, of cis-1,4 units having a low proportion, <1%, of 1,2-vinyl content, and also having a small molar-mass-polydispersity index (MPI), characterized in that Mooney viscosity (ML1+4100° C.) of the polybutadiene is from 70 to 90 and The molar-mass-polydispersity index of the polybutadiene is smaller than 10.

Abstract: A vulcanizable composition of matter comprising a rubber component, a filler, a curative for the rubber, where the rubber component includes a multi-modal polymer including at least two distinct peak molecular weights within a range defined by a lower limit of 80 kg/mole and an upper limit of 500 kg/mole.

Abstract: A method for preparing a functionalized polymer, the method comprising the steps of (i) polymerizing conjugated diene monomer by employing a lanthanide-based catalyst to form a reactive polymer, and (ii) reacting the reactive polymer with a protected oxime compound.

Abstract: A catalyst for polymerization of conjugated diene is provided, which facilitates manufacture of a conjugated diene polymer with a high 1,4-cis structure content, leaves less aluminum residue on polymerization, and has high activity. A method of manufacturing conjugated diene polymers using the catalyst is also provided. A catalyst for polymerization of conjugated diene comprises (A) an yttrium compound; (B) an ionic compound including a non-coordinate anion and a cation; and (C) an organometallic compound including an element selected from the groups 2, 12 and 13 of the periodic table.

Abstract: The present invention provides 1) a complex comprising a mono-anionictridentate ligand, represented by the following general formula (I); 2) a polymerization catalyst composition, comprising the complex; and 3) a cis-1,4-isoprene polymer, a cis-1,4-butadiene polymer, a cis-1,4-isoprene-styrene copolymer, a cis-1,4-butadiene-styrene copolymer, a cis-1,4-butadiene-cis-1,4-isoprene copolymer, and a cis-1,4-butadiene-cis-1,4-isoprene-styrene copolymer, each of which has high-cis-1,4 content in a micro structure and a sharp molecular-weight distribution.

Abstract: Pneumatic rubber tire with an outer, circumferential tread comprised of specialized cis 1,4-polybutadiene rubber based silica/carbon black reinforced rubber composition.

Abstract: This invention provides a polybutadiene capable of improving wear resistance and resistance to crack growth in a rubber composition and a tire, wherein values of e, f and g derived from the following determinant (I): ( 1.7455 0 - 0.0151 - 0.0454 0.4292 - 0.0129 - 0.007 0 0.3746 ) ? ( log 10 ? ( a / d ) log 10 ? ( a / b ) log 10 ? ( a / c ) ) = ( e f g ) ( I ) (wherein a is a mountain peak value around 1130 cm?1 in a transmittance spectrum through Fourier transform infrared spectroscopy (FT-IR), and b is a valley peak value around 967 cm?1, and c is a valley peak value around 911 cm?1, and d is a valley peak value around 736 cm?1) satisfy relationships of equation (II): (Calculated value of cis-1,4 bond)=e/(e+f+g)×100?99 and equation (III): (Calculated value of vinyl bond)=g/(e+f+g)×100?0.

Abstract: A novel process is used to prepare synthetic rubbers (B) which feature very narrow molecular weight distribution and a correspondingly low value for the polydispersity index. The preparation process encompasses the treatment of a synthetic rubber with ultrasound, where the resultant synthetic rubber (B) has a lower weight-average molecular weight (Mw) than the synthetic rubber (A) used. The resultant synthetic rubbers (B) have excellent suitability for processing via extruder processes or injection-moulding processes.

Abstract: A catalyst for polymerization of conjugated diene comprises (A) an yttrium compound; (B) an ionic compound including a non-coordinate anion and a cation; and (C) an organometallic compound including an element selected from the groups 2, 12 and 13 of the periodic table.

Abstract: A process for preparing a polydiene, the process comprising the step of polymerizing conjugated diene monomer in the presence of a dihydrocarbyl ether, where said step of polymerizing employs a lanthanide-based catalyst system.

Abstract: This invention is concerned with a butadiene-based polymer having a high cis-1,4 bond content, a low vinyl bond content and a molecular weight distribution of a specified range, and more particularly a butadiene-based polymer having a 1,3-butadiene monomer unit, characterized in that a cis-1,4 bond content and a vinyl bond content in the 1,3-butadiene monomer unit as measured by a Fourier transform infrared spectroscopy (FT-IR) is not less than 98.0% and not more than 0.3%, respectively, and a ratio (Mw/Mn) of weight average molecular weight (Mw) to number average molecular weight (Mn) is 1.6-3.5.

Abstract: A process for preparing a polydiene, the process comprising the step of polymerizing conjugated diene monomer in the presence of a dihydrocarbyl ether, where said step of polymerizing takes place within a polymerization mixture that includes less than 20% by weight of organic solvent based on the total weight of the polymerization mixture, and where said step of polymerizing employs a lanthanide-based catalyst system that includes the combination of or reaction product of ingredients including (a) a lanthanide compound, (b) an aluminoxane, (c) an organoaluminum compound other than an aluminoxane, and (d) a bromine-containing compound selected from the group consisting of elemental bromine, bromine-containing mixed halogens, and organic bromides.

Abstract: Lithium-terminated polymers of one or more conjugated dienes and of one or more mono alkenyl arenes are coupled by reaction with an alkoxy silane coupling agent having the formula Rx—Si—(OR?)y, where x is 0 or 1, x+y=4, R and R? are the same or different, R is selected from aryl hydrocarbon radicals, linear alkyl hydrocarbon radicals and branched alkyl hydrocarbon radicals, and R? is selected from linear and branched alkyl hydrocarbon radicals, such that the resulting polymer composition contains less than about ten weight percent of uncoupled polymer diblock. The polymer compositions are subsequently selectively hydrogenated, and are useful in a variety of compounds and end use applications.

Abstract: A catalyst composition that is the combination of or the reaction product of ingredients comprising (a) a nickel-containing compound, (b) an alkylating agent, (c) a fluorine-containing compound, and (d) a chlorine-containing compound.

Abstract: A process for preparing a polydiene, the process comprising the step of polymerizing conjugated diene monomer in the presence of a dihydrocarbyl ether, where said step of polymerizing employs a lanthanide-based catalyst system.

Abstract: A golf ball is composed at least in part of a material molded under heat from a rubber composition which includes: (a) a base rubber composed primarily of a mixture of at least 60 wt % of a polybutadiene having a stress relaxation time (T80), defined as the length of time it takes from the moment when rotor rotation is stopped immediately after measurement of the ML1+4 (100° C.) value (the Mooney viscosity measured at 100° C. in accordance with ASTM D-1646-96) for the ML1+4 value to decrease 80%, of less than 4 seconds with up to 40 wt % of a polybutadiene having a stress relaxation time (T80) of at least 4 seconds; (b) an unsaturated carboxylic acid and/or a metal salt thereof; and (c) an organic peroxide. The golf ball has an excellent manufacturability and rebound.

Abstract: The invention relates to a pneumatic tire having excellent mechanical properties by using a rubber composition containing a polybutadiene rubber having a high cis-1,4 bond content, a low vinyl bond content and proper number average molecular weight and molecular weight distribution, and more particularly to a pneumatic tire characterized in that a rubber composition including a polybutadiene with a cis-1,4 bond content of not less than 99.0% and a vinyl bond content of not more than 0.3% as measured by a Fourier transform infrared spectroscopy is used in any one of tire members.

Abstract: A process is described for obtaining a 1,3-butadiene homopolymer by the reaction of a catalytic system in the presence of 1,3-butadiene and one or more monoolefin(s) with 4 carbon atoms. This catalytic system is based on at least: a conjugated diene monomer, an organic phosphoric acid salt of one or more rare earth metals, said salt being in suspension in at least one inert, saturated and aliphatic or alicyclic hydrocarbon solvent, an alkylating agent of the formula AlR3 or HAlR2, where R is an alkyl group, and an alkylaluminum halide halogen donor.

Abstract: A modified diene-?-olefin copolymer which is represented by the formula (1) below and has H2C?C(R5)—COO— in at least a part of the ends. wherein R1 and R2 independently represent a hydroxyl group or H2C?C(R5)—COO—, R3s, R5s, and R6s are independently represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, R4s independently represent a phenyl group, a pyridyl group, a chlorine atom, a cyclohexyl group, or a carbonyloxyalkyl group, and l, m, and n represent the number of repetition.

Abstract: A method for preparing a diene elastomer, such as a butadiene homopolymer or copolymer, in particular, a polybutadiene, with a high level of cis-1,4 linkages that has both a Mooney viscosity greater than or equal to 40 and a polydispersity index of less than 2.1. The method comprises a reaction of a catalyst system with at least one conjugated diene monomer to be polymerized and the catalyst system is based on at least: optionally one preforming conjugated diene; one salt of one or more rare earth metals; an inert hydrocarbon-based solvent; an alkylating agent comprising an allyl derivative of aluminum of formula R?nAlR?3-n, where R? is a saturated or unsaturated alkyl group or else a hydride, where R? is an allyl group and where n is an integer inclusively between 1 and 3; and a halogen donor that belongs to the family of alkylaluminum halides, excluding alkylaluminum sesquihalides.

Abstract: A method for the continuous production of polydienes, the method comprising the steps of (a) charging a mixture of one or more monomer, catalyst system, and less than 50% weight percent organic solvent based on the total weight of the monomer, catalyst and solvent, into first vessel, (b) polymerizing the monomer to a conversion of up to 20% by weight of the monomer to form a mixture of reactive polymer and monomer, (c) removing the mixture of reactive polymer and monomer from the vessel, and (d) terminating the reactive polymer prior to a total monomer conversion of 25% by weight.

Abstract: Conjugated diene polymers having good wear resistance, mechanical properties, storage stability, processability and a reduced cold flow are produced by polymerizing a conjugated diene compound with a catalyst of rare earth element compound, a compound containing at least one halogen atom, an aluminoxane, and an organoaluminum compound in an organic solvent and reacting the resulting polymer just after the polymerization with at least one compound selected from the group consisting of a halogenated organometallic compound, a halogenated metal compound, an organometallic compound, a heterocumulene compound, a hetero three-membered-ring containing compound, a halogenated isocyano compound, a carboxylic acid, an acid halide, an ester compound, a carbonic ester compound, an acid anhydride and a metal salt of a carboxylic acid as a modifying agent.

Abstract: Disclosed herein are a method for preparing a cis-1,4-polybutadiene with a controlled molecular weight distribution, comprising polymerizing butadiene monomers using a rare-earth catalyst system comprising: (a) at least one aliphatic hydrocarbon-soluble organometallic compound comprising at least one metal element chosen from the elements of atomic numbers 51-71 in the periodic table; (b) at least one organoaluminum compound of the formula: AlR1R22, (c) at least one aliphatic hydrocarbon-soluble halogen-containing compound; (d) optionally at least one alkylaluminum alkoxide; and (e) at least one conjugated double bond-containing organic compound, and methods of preparing the rare-earth catalyst system.

Abstract: Lithium-terminated polymers of one or more conjugated dienes and of one or more mono alkenyl arenes are coupled by reaction with an alkoxy silane coupling agent having the formula Rx—Si—(OR?)y, where x is 0 or 1, x+y=4, R and R? are the same or different, R is selected from aryl hydrocarbon radicals, linear alkyl hydrocarbon radicals and branched alkyl hydrocarbon radicals, and R? is selected from linear and branched alkyl hydrocarbon radicals, such that the resulting polymer composition contains less than about ten weight percent of uncoupled polymer diblock. The polymer compositions are subsequently selectively hydrogenated, and are useful in a variety of compounds and end use applications.

Abstract: The present invention relates to a catalyst for polymerization of a conjugated diene or the like, which is composed of a metallocene-type cation complex of a gadolinium compound. Examples of such catalyst include a metallocene-type cation complex of a trivalent gadolinium compound represented by the general formula (I): RaGdXb (wherein, Gd represents gadolinium; R represents a cyclopentadienyl group, a substituted cyclopentadienyl group, an indenyl group, a substituted indenyl group, a fluorenyl group, or a substituted fluorenyl group; X represents an anion; “a” represents an integer of 1 or 2; and “b” represents an integer of 1 or 2). The present invention provides a catalyst by which polymerization of a conjugated diene or copolymerization of a conjugated diene and an aromatic vinyl compound can be carried out efficiently and inexpensively.

Abstract: A process for the preparation of low branch content polybutadiene comprising: (a) a first butadiene polymerisation stage; (b) treatment of the polymer solution obtained upon completion of stage (a) with a coupling agent selected from: (i) polyunsaturated natural oils; (ii) butadiene and/or isoprene oligomers; (iii) butadiene and/or isoprene co-polymers with vinylarene monomers; the unsaturations present in compounds (i)–(iii) being at least partially substituted with groups selected from epoxides, anhydrides and esters; (c) recovery of the low branch content polybutadiene obtained upon completion of stage (b).

Abstract: A method of producing cis-1,4-polydienes, the method comprising the step of contacting conjugated diene monomer with a lanthanide-based catalyst system in the presence of less than 20% by weight of organic solvent based on the total weight of monomer, organic solvent, and resulting polymer, where the lanthanide-based catalyst system is the combination of or reaction product of (a) a lanthanide compound, (b) an organoaluminum hydride, (c) a trihydrocarbylaluminum, and (d) a halogen-containing compound.

Abstract: This invention is based upon the unexpected discovery that alkylated diphenylamines can be used in conjunction with nickel based catalyst systems which contain (a) an organonickel compound, (b) an organoaluminum compound, and (c) a fluorine containing compound to produce cis-1,4-polybutadiene having reduced molecular weight and an increased level of branching. This results in the cis-1,4-polybutadiene exhibiting good processability without sacrificing cold flow characteristics. Additionally, the alkylated diphenylamine which remains in the rubber acts in a manner which provides it with antioxidant protection. In other words, the use of alkylated diphenylamines accomplishes the three major objectives that are realized by employing para-styrenated diphenylamines (reduced molecular weight, regulated polymer macrostructure through branching and antidegradant protection).