Abstract: The invention relates to an initiator composition for anionic polymerization, comprising at least one alkali metal hydride selected from LiH, NaH, and KH, and at least one organylaluminum compound, and to a process for the anionic polymerization of styrene monomers or of diene monomers using the initiator composition.

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 preparation process for a copolymer having two blocks usable in a sulphur-cross-linkable rubber composition of reduced hysteresis in the cross-linked state, such a block copolymer in which one of the blocks is a polyisoprene and the other a diene elastomer other than a polyisoprene, and this rubber composition for tire treads. A process for the preparation of this copolymer involves copolymerizing one or more monomers including a conjugated diene other than isoprene using a catalytic system including at least one hydrocarbon solvent, a compound A of a metal of group IIIA, a compound B of an alkaline-earth metal and a polymeric initiator C having a C—Li bond which is constituted of a monolithiated polyisoprene intended to form the polyisoprene block, the number-average molecular weight Mn1 of the polyisoprene block being between 2,500 and 20,000 g/mol.

Abstract: A process is described for obtaining from an “FCC” initial C5 fraction which is enriched with isoprene and purified and usable for the selective polymerization of isoprene. A process is also described for obtaining an isoprene homopolymer from a polymerization medium comprising isoprene and at least one methyl butene, such as said “FCC” C5 fraction which is enriched with isoprene and purified. The process of obtaining the final fraction from the initial C5 fraction includes: a catalytic hydrogenation reaction of said initial C5 fraction by a palladium-based catalyst, which produces an intermediate C5 fraction comprising n-pentenes in a mass ratio which is less than 0.

Abstract: The invention is directed to a pneumatic tire having at least one component comprising a vulcanizable rubber composition, wherein the vulcanizable rubber composition comprises, based on 100 parts by weight of elastomer (phr), from about 30 to 100 phr of high trans random SBR, and from about zero to about 70 phr of at least one additional elastomer, wherein the high trans random SBR comprises from about 3 to about 30 percent by weight of styrene.

Abstract: The present invention provides synthetic polyisoprenes having a high cis-1,4 linkage content and a process for their preparation. The synthetic polyisoprenes according to the invention have a cis-1,4 linkage content, measured by carbon-13 nuclear magnetic resonance and/or medium-wave infrared radiation analysis, of greater than 99.0%. The process for the preparation of these synthetic polyisoprenes involve polymerizing, at a temperature of 0° C. or lower, isoprene in the presence of a catalytic system based on: a) a conjugated diene monomer, b) an organic phosphoric acid salt of one or more rare earth, c) an alkylaluminium alkylating agent of the formula AlR3 or HAlR2, and d) a halogen donor consisting of an alkylaluminium halide, wherein the salt is suspended in at least one inert, saturated aliphatic or alicyclic hydrocarbon solvent and the alkylating agent:rare earth salt molar ratio ranges from 1 to 5.

Abstract: The present invention relates to a process for obtaining a polyisoprene having a high cis-1,4 linkage content, from a steam-cracked C5 naphtha fraction enriched with isoprene. The process of the present invention comprises reacting a steam-cracked C5 naphtha fraction in the presence of a catalytic system, wherein the C5 fraction is enriched with isoprene such that the mass fraction of isoprene in said enriched fraction lies within a range of from 30% to 95%, and the catalytic system is based on at least (a) a conjugated diene monomer, (b) an organic phosphoric acid salt of one or more rare earth metals, (c) an alkylating agent consisting of an alkylaluminum of the formula AlR3 or HAlR2, and (d) a halogen donor consisting of an alkylaluminum halide, said salt being suspended in at least one inert saturated hydrocarbon solvent of aliphatic or alicyclic type which is included in said catalytic system, and the molar ratio of alkylating agent:rare earth salt is in a range of from 1 to 5.

Abstract: The present invention provides a catalytic system that can be used to prepare by polymerization diene elastomers comprising polyisoprenes and polybutadienes. The invention also provides a process for the preparation of the catalytic system and to a process using the catalytic system to prepare diene elastomers comprising polyisoprenes having a high cis-1,4 linkage content and polybutadienes. The catalytic system according to the invention is based on (a) a conjugated diene monomer, (b) an organic phosphoric acid salt of a rare earth metal, (c) an alkylating agent consisting of an alkylaluminium of the formula AlR3 or HAlR2, and (d) a halogen donor consisting of an alkylaluminium halide, and is such that said salt is suspended in at least one inert and saturated aliphatic or alicyclic hydrocarbon solvent and, the “alkylating agent:rare earth salt” molar ratio ranges from 1 to 5.

Abstract: The invention is directed to a pneumatic tire having at least one component comprising a vulcanizable rubber composition, wherein the vulcanizable rubber composition comprises, based on 100 parts by weight of elastomer (phr), from about 30 to 100 phr of high trans random SBR, and from about zero to about 70 phr of at least one additional elastomer, wherein the high trans random SBR comprises from about 3 to about 30 percent by weight of styrene.

Abstract: The invention provides olefin polymerization catalyst exhibiting excellent polymerization activities, a process for olefin polymerization using the catalyst, a novel transition metal compound useful for the catalyst, and an &agr;-olefin/conjugated diene copolymer having specific properties. The olefin polymerization catalyst of the invention comprises (A) a transition metal compound of formula (I) or (II), and (B) an organometallic compound, an oranoaluminum oxy-compound or an ionizing ionic compound. The novel transition metal compound of the invention is a compound of formula (I) wherein M is a transition meal atom of Group 3 or 4 of the periodic table; m is an integer of 1 to 3; R1 is a hydrocarbon group, etc.; R2 to R5 are each H, a halogen, a hydrocarbon group, etc.; R6 is a halogen, a hydrocarbon group, etc.; n is a number satisfying a valence of M; and X is a halogen, a hydrocarbon group, etc.

Abstract: Ethylene, dienes and optionally &agr;-olefins are copolymerized by selected iron complexes of 2,6-pyridinecarbox-aldehydebis(imines) and 2,6-diacylpyridinebis(imines). The resulting copolymers contain residual olefinic unsaturation from the diene monomers, and some of these copolymers contain cyclic units in the main chain.

Abstract: The invention is directed to a pneumatic tire having at least one component comprising a vulcanizable rubber composition, wherein the vulcanizable rubber composition comprises, based on 100 parts by weight of elastomer (phr), from about 30 to 100 phr of high trans random SBR, and from about zero to about 70 phr of at least one additional elastomer, wherein the high trans random SBR comprises from about 3 to about 30 percent by weight of styrene.

Abstract: Ethylene, dienes and optionally &agr;-olefins are copolym-erized by selected iron complexes of 2,6-pyridinecarbox-aldehydebis(imines) and 2,6-diacylpyridinebis(imines). The resulting copolymers contain residual olefinic unsaturation from the diene monomers, and some of these copolymers contain cyclic units in the main chain.

Abstract: This invention discloses a chewing gum rubber composition (gum base) that utilizes carnosic acid from a Libiatae plant, such as rosemary or sage, as an antioxidant stabilizer. This invention more specifically discloses a chewing gum base comprising: (1) about 5 weight percent to about 95 weight percent of a rubbery elastomer; (2) about 0 weight percent to about 75 weight percent of an elastomer plasticizer selected from the group consisting of natural rosin esters and synthetic terpene resins; (3) about 1 weight percent to about 65 weight percent of a filler material; and (4) carnosic acid, wherein said chewing gum base is void of sweeteners, flavoring agents or colors.

Abstract: Amino acid functionalized polymers useful for graft copolymerization prepared by reacting a mixture containing, for chain transfer, a thio-substituted amino acid and an ethylenically unsaturated monomer.

Abstract: The group IIa metal containing catalyst system of this invention can be utilized to synthesize rubbery polymers having a high trans microstructure by solution polymerization. Such rubbery polymers having a high trans microstructure content, such as polybutadiene rubber, styrene-isoprene-butadiene rubber, styrene-butadiene rubber, can be utilized in tire tread rubbers that exhibit improved wear and tear characteristics. This invention more specifically reveals a catalyst system which is comprised of (a) an organolithium compound, including organolithium functionalized compounds, (b) a group IIa metal salt selected from the group consisting of group IIa metal salts of di(alkylene glycol)alkylethers and group IIa metal salts of tri(alkylene glycol) alkylethers, and (c) an organoaluminum compound, and optionally an organomagnesium compound.

Abstract: Deaminatively generated carbocations to initiate addition polymerization are disclosed. The high reactivity of the carbocation allows initiation of polymerization with virtually all alkenes, alkynes, alicyclic and aromatic monomers, regardless whether multisubstituted or conjugated. In addition, the carbocation initiates a polymerization reaction that generates an extremely high molecular weight polymer. In particular polystyrene of viscosity average molecular weight of approximately 106 was obtained.

Abstract: This invention is based upon the discovery that rubbery polymers having a high vinyl content and a low degree of branching can be synthesized with an initiator system that is comprised of (a) a lithium initiator selected from the group consisting of allylic lithium compounds and benzylic lithium compounds, (b) a Group I metal alkoxide, and (c) a polar modifier; wherein the molar ratio of the Group I metal alkoxide to the polar modifier is within the range of about 0.1:1 to about 10:1; and wherein the molar ratio of the Group I metal alkoxide to the lithium initiator is within the range of about 0.01:1 to about 20:1. These high vinyl polymers offer reduced levels of hysteresis and better functionalization efficiency.

Abstract: In a process for polymerizing dienes in a solvent comprising vinylaromatic monomers, the polymerization is carried out in the presence of a metal compound of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo or W as catalyst and a Lewis acid as cocatalyst and, if desired, an alkylating agent and, if desired, a regulator. This process can be used for preparing high-impact polystyrene, acrylonitrile-butadiene-styrene copolymers or methyl methacrylate-butadiene-styrene copolymers.

Abstract: The invention is related to a novel compound represented by NdHA4 wherein A is a carboxylate, and to a diene polymerization catalyst using the novel compound. NdHA4 has monomeric structure and does not contain water, bases and salts. NdHA4 is mixed with a halogen compound and an organic metal compound to prepare a catalyst system. The catalyst system in the polymerization of 1,3-butadiene (BD) or isoprene produces high cis polydiene with a high activity (100 g BD/4.0×10−5 mole Nd) and without gel formation. The polydiene thus obtained is useful for tires and golf balls and as a polystyrene modifier.

Abstract: A polymer of ethylene and at least one alpha olefin having at least 5, carbon atoms obtainable by a continuous gas phase polymerization using supported catalyst of an activated molecularly discrete catalyst such as a metallocene in the substantial absence of an aluminum alkyl based scavenger which polymer has a Melt Index (MI) as herein defined of from 0.1 to 15; a Compositional Distribution Breadth Index (CDBI) as defined herein of at least 70%, a density of from 0.910 to 0.930 g/ml; a Haze value as herein defined of less than 20%; a Melt Index ratio (MIR) as herein defined of from 35 to 80; an averaged Modulus (M) as herein defined of from 20 000 to 60 000 psi (pounds per square inch) and a relation between M and the Dart Impact Strength in g/mil (DIS) complying with the formula: DIS≧0.8×[100+e(11.71-0.000268×M+2.183×10−9×M2)].

Abstract: Endodontic sealant compositions and methods for sealing a root canal using sealant or other filling materials. The compositions include one or more resins that promote adhesion to hydrophilic dental tissues. Examples include alkyl methacrylates and derivatives thereof, such as alkylamino methacrylates and oxyphosphoro methacrylates. The compositions include a radio opacifying agent, so that they may be seen using X-rays, and one or more polymerization initiators to effect curing, typically both chemical and photo initiators to yield a dual cure sealant composition. The compositions are introduced into the root canal using a narrow cannula coupled to a high pressure hydraulic delivery device. Additional pressure may be applied to the sealant compositions using a syringe-like plunger introduced within a cylindrical access hole drilled through the crown of the tooth.

Abstract: A process for production of diene rubber polymers wherein, during production of a diene rubber polymer by emulsion polymerization, the polymerization is initiated using a portion of the starting material and the polymerization is continued with either continuous or intermittent dropwise addition of the remainder of the starting material during the polymerization, and wherein at least ½ of the total amount of the water and of the monomer in the starting material used is added dropwise during the polymerization, and the temperature of the dropwise added water and monomer is kept to at least 20° C. below the polymerization temperature. The process can produce industrially useful diene rubber polymer latexes at a high productivity rate.

Abstract: The present invention provides a process for preparing a branched diene elastomer having a high proporation of starred chains comprising anionically polymerizing at least one conjugated diene monomer having 4 to 12 carbons in a polymerization medium comprising a hydrocarbon solvent, such as cyclohexane, and an organometallic initiator, such as n-butyllithium, wherein tris-(2,4-di-tert-butylphenyl)phosphite is added to the polymerization medium as a starring agent during or at the end of polymerization in an amount such that the molar ratio of the starring agent to the initiator is between 0.1 and 1.5, preferably between 0.2 and 0.5. The process produces a branched diene elastomer having a high proportion of starred chains. The elastomer can be a homopolymer, such as polybutadiene or polyisoprene or a copolymer, such as polystyrene/polybutadiene.

Abstract: Amorphous polymers, including homopolymers and co-polymers, containing residues of vinyl cyclohexane and/or substituted vinyl cyclohexane are described. The polymers of the present invention have a syndiotactic configuration in which the quantity of diads is greater than 50.1% and less than 74%. The polymers of the invention have high transparency, low birefringence and high heat defection temperature, and can be used to prepare molded articles (e.g., optical data storage media and lenses) and films.

Abstract: Group 4 metal-containing organosilicon dendrimers are described. Also described are methods for synthesizing the dendrimers. The dendrimers can be useful in several applications including as olefin polymerization and copolymerization catalysts and as silane polymerization catalysts.

Abstract: Solid acids are used as catalysts for the polymerization of a feed stream containing at least one of pure monomer, C5 monomers, and C9 monomers to produce hydrocarbon resins. Freely-associated water may be removed from the solid acid catalyst prior to use. Resins with softening points (Ring and Ball) in the range of about 5° C. to 170° C. can be prepared. These catalysts offer advantages over the traditional Friedel-Crafts polymerization catalysts since the acid sites are an integral part of the solid. The solid acid catalysts are relatively nonhazardous, reusable catalysts which eliminate or at least reduce contamination of the resulting resin products with acid residues or by-products.

Abstract: The present invention relates to an ethylene-isoprene random copolymer having an isoprene content of about 1 to 45% by mole, or an ethylene-isoprene copolymer having a Q-value of about 3.5 or less, wherein the Q-value is a ratio of weight average molecular weight (Mw) to number average molecular weight (Mn) The copolymer may be made using a catalyst comprising a compound of formula I, II or III, wherein M1 is a group IV transition metal, J is a group XIV atom, A and X3 are group XVI atoms, and Cp1 is a cyclopentadienyl-type group.

Abstract: The invention relates to novel microgel-containing essentially organic solvent nail varnishes. The microgels are particularly acrylic microgels. The invention also relates to the use of these microgels for modifying the physical properties of an essentially organic solvent nail varnish composition, and/or the properties of the film obtained during the application of said composition.

Abstract: Fluorinated solid acids and supported fluorinated solid acids are used as catalysts for the polymerization of a feed stream containing at least one of pure monomer, C5 monomers, and C9 monomers to produce hydrocarbon resins. Freely-associated water may be removed from the fluorinated solid acid catalyst and/or supported fluorinated solid acid catalyst prior to use. Resins with softening points (Ring and Ball) in the range of about 5° C. to 170° C. can be prepared. These catalysts offer advantages over the traditional Friedel-Crafts polymerization catalysts since the acid sites are an integral part of the solid. The fluorinated solid acid catalysts and supported fluorinated solid acid catalysts are relatively nonhazardous, reusable catalysts which eliminate or at least reduce contamination of the resulting resin products with acid residues or by-products.

Abstract: A rubber cement for marking unvulcanized rubber which comprises, as a seed rubber, a rubber composition comprising a rubber component comprising at least one rubber selected from natural rubber and diene rubbers, silica and titanium dioxide.

Abstract: A polymer of ethylene and at least one alpha olefin having at least 5, carbon atoms obtainable by a continuous gas phase polymerization using supported catalyst of an activated molecularly discrete catalyst such as a metallocene in the substantial absence of an aluminum alkyl based scavenger which polymer has a Melt Index (MI) as herein defined of from 0.1 to 15; a Compositional Distribution Breadth Index (CDBI) as defined herein of at least 70%, a density of from 0.910 to 0.930 g/ml; a Haze value as herein defined of less than 20%; a Melt Index ratio (MIR) as herein defined of from 35 to 80; an averaged Modulus (M) as herein defined of from 20 000 to 60 000 psi (pounds per square inch) and a relation between M and the Dart Impact Strength in g/mil (DIS) complying with the formula: DIS≧0.8×[100+e(11.71−0.000268×M+2.183×10−9×M2)].

Abstract: Styrene butadiene rubber (SBR) is widely used as a chewing gum base in lieu of natural gums. It is necessary to protect chewing gum SBR with a food grade antioxidant stabilizer system. This invention discloses a chewing gum rubber composition (gum base) that utilizes carnosic acid from a Libiatae plant, such as rosemary or sage, as an antioxidant stabilizer.