Abstract: Process for the preparation of polybutadiene with a low branching degree which comprises: (a) a first polymerization step of butadiene in the presence of organic solvents and in the presence of a catalytic system comprising (a1) a derivative of neodymium; (a2) an aluminum alkyl having general formula (I) AlR1R2R3; (a3) an organo aluminum derivative containing at least one halogen atom, preferably chlorine; the above first step being carried out up to a conversion of butadiene >98% to give a linear polybutadiene (gm=1) with a content of 1,4-cis units greater than 93% and a Mw/Mn ranging from 2.2 to 2.9; (b) treatment of the polymeric solution obtained at the end of step (a) with a peroxide, (c) recovery of the polybutadiene with a low branching degree obtained at the end of step (b).

Abstract: The present invention relates to a polymer composite containing at least one carboxylated nitrile rubber polymer, that is optionally hydrogenated, at least one basic compound, at least one polyhalogenated hydrocarbon, optionally at least one filler and optionally at least one cross-linking agent, a process for preparing said polymer composite wherein at least one carboxylated nitrile rubber polymer, that is optionally hydrogenated, at least one basic compound, at least one polyhalogenated hydrocarbon, optionally at least one filler and optionally at least one cross-linking agent are mixed and a shaped article containing diester bridges formed by reaction of at least one carboxylated nitrile rubber polymer, that is optionally hydrogenated, at least one basic compound and at least one polyhalogenated hydrocarbon.

Abstract: A curable composition includes an unsaturated polyester and an unsaturated monomer copolymerisable with the unsaturated polyester in the presence of polymerisation accelerators and initiators. The unsaturated polyester is an epoxidised unsaturated polyester obtainable by reaction between unsaturated polyester obtainable by reaction between the carboxy end groups of a polyester having unsaturated monomer units and the epoxy groups of an epoxy resin.

Abstract: The partially condensed fluid recycle stream of a fluidized bed polyolefin reactor operating in the condensing mode is split into two portions by a stream splitter. In a preferred mode, the smaller stream from the splitter contains a higher ratio of liquid to gas than the larger stream. One portion of the split stream is injected below the fluidized bed and the other, preferably with enhanced liquid content, is injected into the fluidized bed at a level above the product withdrawal level. Regulation of liquid injection above the product withdrawal level, as a function of liquid in the product discharge tanks, reduces the liquid in the product discharge system, resulting in improved discharge cycle times and more efficient conservation of monomer and other materials which might otherwise be lost in the discharge process.

Abstract: The invention provides a process for the telomerization of acyclic olefins having at least two conjugated double bonds (I) or mixtures comprising such olefins by means of nucleophiles (II) using a palladium-carbene complex as catalyst.

Abstract: The present invention relates to a method of estimating the properties of a polymer product by using converted process variables (cPV's) which means process variable that final or intermediate product experienced earlier in average in the reactors by stage with respect to the final product, which incorporates residence time distribution to process variables, wherein said method comprises the following steps of: computing cPV's by incorporating the residence time distribution to said process variables by means of theoretically determining the amounts of content and discharge of the product in the process, and then solving the balance equations of a hypothetical substance by taking the respective process variables as those of the hypothetical substance: and estimating the properties of the product by inputting to various property estimation models cPV's in the reactors by stage with respect to the final product after incorporating the residence time distribution to said process variables.

Abstract: The present invention relates to a process for the preparation of acetal polymers, in particular of polyoxymethylene (POM) by cationic polymerization where organophosphonic and/or organophosphinic acids and/or their derivatives and/or their precursors are used as the initiator.

Abstract: An olefin/aromatic vinyl compound copolymer which is excellent in transparency and which satisfies flexibility and heat resistance simultaneously can be produced by carrying out polymerization in such a manner that at least one of conditions: (a) the polymerization is carried out to an aromatic vinyl compound monomer conversion ratio of at least 50 mol % when the polymerization is completed, and (b) the polymer concentration is at least 10 mass % relative to the polymerization solution when the polymerization is completed, is satisfied, and the olefin partial pressure is changed so that the olefin partial pressure when the polymerization is completed is from 1.3 to 20 times the olefin partial pressure at the initiation of the polymerization.

Abstract: This invention discloses a rubbery polymer which is comprised of repeat units that are derived from (1) at least one conjugated diolefin monomer, and (2) at least one leaving group-bearing monomer having the structural formula: wherein R represents an alkyl group containing from 1 to about 10 carbon atoms or a hydrogen atom, wherein R? represents a methyl group or a hydrogen atom, with the proviso that if R represents an alkyl group then R? represents a hydrogen atom, and wherein R1 and R2 can be the same or different, wherein R1 represents an alkyl group that is functionalized with a leaving group, wherein R2 represents a moiety selected from the group consisting of hydrogen atoms, alkyl groups containing from 1 to 18 carbon atoms, aryl groups containing from 6 to 18 carbon atoms, alkaryl groups containing from 7 to 18 carbon atoms, and alkyl groups that are functionalized with a leaving group.

Abstract: A melt-moldable, thermoplastic norbornene resin composition characterized by being obtained by compounding (A) a base polymer comprising a thermoplastic norbornene resin with (B) an olefin compound having a number-average molecular weight of 200 to 10,000 and a softening point of 70 to 170° C.; and a molded article or optical film obtained by melt-molding or extrusion-molding the thermoplastic norbornene resin composition.

Abstract: A cyclic olefin addition copolymer obtained by copolymerizing a cyclic olefin compound having a side chain substituent group with a ring structure, such as endo-tricyclo[4.3.0.12,5]deca-3,7-diene or endo-tricyclo[4.3.0.12,5]deca-3-ene, with another cyclic olefin compound such as bicyclo[2.2.1]hept-2-ene, and further with a cyclic olefin compound having a hydrolysable silyl group as needed, or hydrogenating after copolymerization; a composition for crosslinking in which a specific crosslinking agent is incorporated; a crosslinked product obtained by crosslinking the composition; an optical material containing the copolymer, the composition or the crosslinked product; and a method for producing the copolymer in which addition polymerization is conducted using a specific nickel catalyst.

Abstract: A method of preparing a polymer under predetermined temperature conditions comprises conducting the polymerization within a closed reaction chamber configured such that most or all of an inner surface has heat exchange capability. The chamber's dimensions are such that the polymerization mixture contacts the effective heat exchange surface sufficiently to ensure that the temperature throughout the polymerization mixture does not vary more than a few degrees from a desired temperature. In one embodiment the chamber is formed of two adjacent, parallel heat exchange plates, wherein at least one plate has a peripheral lip which, in contact with the opposing plate, forms the closed chamber. Multiple plates can be arrayed to form multiple chambers, and each chamber's polymerization temperature, as well as resident polymerization mixture, can be individually predetermined.

Abstract: A slurry polymerization process removes a portion of the fluid slurry without using a settling leg or a continuous take-off. The process uses a reactor take-off valve that is periodically fully closed and fully opened such that the withdrawn slurry is removed from the reactor in a discontinuous manner. The regular, periodic full closing and full opening of the take-off valve reduces instances of polymer plugging the take-off valve. In another aspect of the invention, a take-off valve is throttled in a repetitive pattern to reduce plugging of the take-off valve.

Abstract: A method of improving the brake and clutch capacity of a functional fluid comprising adding a friction-modifying amount of a polyalkenyl sulfonate to the functional fluid, wherein the polyalkenyl sulfonate is an alkali metal or alkaline earth metal salt of a polyalkene sulfonic acid derived from a mixture of polyalkenes comprising greater than about 20 mole percent alkyl vinylidene and 1,1-dialkyl isomers.

Abstract: A stable free radical process for preparing a polymer having acid anhydride functionality includes heating a mixture comprised of a stable free radical agent, maleic anhydride or derivative thereof, and at least one polymerizable electron donor monomer to initiate exothermic reaction and during exotherm of the reaction, adding additional amounts of stable free radical agent to control the reaction temperature. The mixture may also include a stable free radical initiator. In the mixture, the maleic anhydride or derivative thereof preferably comprises from about 10% to about 70%, molar basis, of a total amount of the maleic anhydride or derivative thereof and the at least one polymerizable electron donor monomer. Typically, the heating is to a temperature of from about 100° C. to about 160° C., and the rate of addition of the additional amounts of stable free radical agent is adjusted to control the reaction temperature to be about 160° C. or less.

Abstract: 1,3-Butadiene is polymerized in a hydrocarbon solvent using a catalyst system containing (A) a cobalt salt, (B1) a phosphine compound having one branched aliphatic group of 3 or more carbon atoms or one alicyclic group of 5 or more carbon atoms and two aromatic groups, and (C) an organic aluminum compound, or a catalyst system containing (A) a cobalt salt, (B) (B1) a phosphine compound having one branched aliphatic group of 3 or more carbon atoms or one alicyclic group of 5 or more carbon atoms and two aromatic groups and/or (B2) a triarylphosphine compound having three aromatic groups, (C) an organic aluminum compound and (D) an active halogen-containing compound, thereby obtaining crystalline 1,2-polybutadiene.

Abstract: The present invention provides a supported catalyst comprising (A) a polymer (B) a supporter, (C) a transition metal compound, and optionally (D) (a) a compound which can form an ionic complex by the reaction with the transition metal compound or (b) a specific oxygen-containing compound, and (E) an alkylaluminum compound. The supported catalyst according to present invention, which has a high activity, can be used for preparing a styrenic polymer with a high syndiotacticity. The supported catalyst can be used in combination with a cocatalyst, preferably an alkyl aluminoxane.

Abstract: There is provided an ethylene-?-olefin-non-conjugated diene copolymer rubber satisfying the following requirements (1) to (4): (1) a ratio of a Z-average molecular chain length (Az) measured according to a gel permeation chromatography to a number average molecular chain length (An), Az/An, of the ethylene-?-olefin-non-conjugated diene copolymer rubber is from 20 to 30, (2) a ratio of a weight average molecular chain length (Aw), which is an index of a molecular weight distribution, to the number average molecular chain length (An), Aw/An, of the ethylene-?-olefin-non-conjugated diene copolymer rubber is more than 5, (3) a unimodal or bimodal molecular weight distribution structure having a molecular chain length component, which component is present in a maximum amount in a range of 3.8<Log Aw<4.5, exists in the ethylene-?-olefin-non-conjugated diene copolymer rubber, and (4) a viscosity (ML1+4, 121° C.

Abstract: A monomer is selected to produce a polymeric film having desirable characteristics for a particular application. The monomer is ppolymerized under controlled conditions to produce a solid oligomer having those characteristics at a molecular weight suitable for evaporation under vacuum at a temperature lower than its thermal decomposition temperature. The process of polymerization to produce the oligomer is carried out under conditions that yield a finite molecular-chain length with no residual reactive groups. The solid oligomer so produced is extruded as a film onto a revolving drum (38) in the evaporation section (40) of a vapor deposition chamber, and then cryocondensed on a cold substrate (44) to form a solid film having the same characteristic selected in the solid oligomer constituting the starting material. As a result of the initial complete reaction to produce the oligomer, the thin-film product does not contain unreacted groups and all attendant disadvantages are avoided.

Abstract: A process for producing a vinyl chloride-based polymer by suspension polymerization is provided. The polymerization is initiated in the presence of (A) a particular hydroxypropylmethylcellulose, (B) a particular partially saponified PVA with a saponification degree of 75 to 85 mol % and an average polymerization degree of 1000 to 3000, and (C) a particular partially saponified PVA with a saponification degree of 20 to 57 mol % and an average polymerization degree of 150 to 600 in a specified ration, and said (C) is also additionally added to the polymerization system when a conversion rate is 15–50%. Polymers with a high porosity, excellent plasticizer absorption, extremely low levels of fish eyes, and a high bulk specific gravity are produced at a high level of productivity.