Abstract: The present invention relates to the field of tailored di-, tri- and multi-block as well as gradient polyesters/polycarbonates copolymers prepared by introducing monomers simultaneously in the reaction medium in the presence of an organometallic, metal salt or organic catalyst.

Abstract: A supported catalyst system may include a titanated silica-containing catalyst support having at least 0.1 wt % of Ti and a specific surface area of from 150 m2/g to 800 m2/g. The Ti may be of a titanium compound of the general formula selected from RnTi(OR?)m, and (RO)nTi(OR?)m, wherein R and R? are the same or different and are selected from hydrocarbyl groups containing from 1 to 12 carbons or halogens, wherein n is 0 to 4, wherein m is 0 to 4, and wherein m+n equals 4. The supported catalyst system may include a catalyst activating agent and a metallocene. The supported catalyst system may be obtained by a process including titanating a silica-containing catalyst support with at least one vaporized titanium compound, and treating the titanated silica-containing catalyst support with a catalyst activating agent and a metallocene.

Abstract: A supported catalyst system includes a coprecipitated silica- and titania-containing support, alumoxane, and a metallocene. The supported catalyst system has a Ti content of at least 0.1 wt %.

Abstract: Poly(carbonate-urethane) or poly(ester-urethane) may be characterized in that of carbonate soft segments have molecular weights Mn ranging between 10,000 and 250,000 g/mol. The segments' length may be monitored by the ring-opening polymerization condition. The process of preparing the poly(carbonate-urethane) or poly(ester-urethane) may include immortal ring-opening polymerization of a cyclic carbonate or of a cyclic ester or diester monomers in the presence of a first catalyst system and diols or polyols. The process may include chemical modification of the hydroxyl chain-end groups into carboxylic groups in the presence of a second catalyst system. The process may include a coupling reaction with at least 2 equivalents of a second cyclic carbonate, enabling coupling with the carboxylic moiety in the presence of a third catalyst system.

Abstract: A process may include contacting an olefin monomer and a racemic bridged metallocene catalyst at a temperature of 80° C. to 150° C. in the presence of hydrogen. The racemic bridged metallocene catalyst may include a metallocene compound (A) and an activator component (B). The process may include recovering an effluent containing polyalpha-olefins (PAOs). The metallocene compound (A) may be represented by the formula R(Cp1)(Cp2)MX1X2. In the formula, R may be a C1-C20 alkylene bridging group; Cp1 and Cp2 may be the same or different substituted or unsubstituted tetrahydroindenyl rings; M may be a transition metal; and X1 and X2 may be independently selected from hydrogen, halogen, hydride radicals, hydrocarbyl radicals, substituted hydrocarbyl radicals, halocarbyl radicals, substituted halocarbyl radicals, silylcarbyl radicals, substituted silylcarbyl radicals, germlcarbyl radicals, substituted germylcarbyl radicals.

Abstract: The present invention relates to a method for optimizing the sequential use of at least two ethylene polymerization catalysts to an ethylene polymerization loop reactor, comprising: transferring to a mixing vessel a first ethylene polymerization catalyst and a first diluent, thereby providing a first catalyst slurry, transferring said first catalyst slurry from said mixing vessel to an ethylene polymerization loop reactor at a concentration suitable for polymerizing ethylene, increasing the ratio of said diluent to said first ethylene polymerization catalyst in said first catalyst slurry, stopping the supply of said first catalyst slurry to said mixing vessel, stopping the supply of said first catalyst slurry to said ethylene polymerization loop reactor, stopping the supply of ethylene to said ethylene polymerization loop reactor, removing said first catalyst slurry from said ethylene polymerization loop reactor, emptying said mixing vessel, optionally rinsing said mixing vessel with fresh diluent, transfe

Abstract: supported catalyst system may include a titanated silica-containing catalyst support having at least 0.1 wt % of Ti and a specific surface area of from 150 m2/g to 800 m2/g. The Ti may be of a titanium compound of the general formula selected from RnTi(OR?)m, and (RO)nTi(OR?)m, wherein R and R? are the same or different and are selected from hydrocarbyl groups containing from 1 to 12 carbons or halogens, wherein n is 0 to 4, wherein m is 0 to 4, and wherein m+n equals 4. The supported catalyst system may include a catalyst activating agent and a metallocene. The supported catalyst system may be obtained by a process including titanating a silica-containing catalyst support with at least one vapourised titanium compound, and treating the titanated silica-containing catalyst support with a catalyst activating agent and a metallocene.

Abstract: A process for preparing a supported catalyst system comprising the following steps: a. titanating a silica-containing catalyst support having a specific surface area of from 150 m2/g to 800 m2/g, preferably 280 to 600 m2/g, with at least one vaporized titanium compound of the general formula selected from RnTi(OR?)m and (RO)nTi(OR?)m, wherein R and R? are the same or different and are selected from hydrocarbyl groups containing from 1 to 12 carbon and halogens, and wherein n is 0 to 4, m is 0 to 4 and m+n equals 4, to form a titanated silica-containing catalyst support having at least 0.1 wt % of Ti based on the weight of the titanated silica-containing catalyst support, b. treating the support with a catalyst activating agent, preferably an alumoxane. c. treating the titanated support with at least one metallocene during or after step (b).

Abstract: Poly(carbonate-urethane) or poly(ester-urethane) may be characterised in that of carbonate soft segments have molecular weights Mn ranging between 10,000 and 250,000 g/mol. The segments' length may be monitored by the ring-opening polymerisation condition. The process of preparing the poly(carbonate-urethane) or poly(ester-urethane) may include immortal ring-opening polymerisation of a cyclic carbonate or of a cyclic ester or diester monomers in the presence of a first catalyst system and diols or polyols. The process may include chemical modification of the hydroxyl chain-end groups into carboxylic groups in the presence of a second catalyst system. The process may include a coupling reaction with at least 2 equivalents of a second cyclic carbonate, enabling coupling with the carboxylic moiety in the presence of a third catalyst system.

Abstract: The invention relates to a process for the preparation of a particulate polyethylene product in a loop reactor, wherein the polymerization catalyst applied in the polymerization process comprises a particulate metallocene-alumoxane catalyst immobilized on a porous silica support; and whereby said metallocene-alumoxane catalyst is heterogeneously distributed on said porous silica support.

Abstract: The present invention relates to a method for optimizing the sequential use of at least two ethylene polymerization catalysts to an ethylene polymerization loop reactor, comprising: transferring to a mixing vessel a first ethylene polymerization catalyst and a first diluent, thereby providing a first catalyst slurry, transferring said first catalyst slurry from said mixing vessel to an ethylene polymerization loop reactor at a concentration suitable for polymerizing ethylene, increasing the ratio of said diluent to said first ethylene polymerization catalyst in said first catalyst slurry, stopping the supply of said first catalyst slurry to said mixing vessel, stopping the supply of said first catalyst slurry to said ethylene polymerization loop reactor, stopping the supply of ethylene to said ethylene polymerization loop reactor, removing said first catalyst slurry from said ethylene polymerization loop reactor, emptying said mixing vessel, optionally rinsing said mixing vessel with fresh diluent, transfe

Abstract: The present invention discloses a method for preparing poly(carbonate-urethane) or poly(ester-urethane) without isocyanate.

Abstract: The present invention relates to a method for optimizing the sequential use of at least two ethylene polymerization catalysts to an ethylene polymerization loop reactor, comprising: transferring to a mixing vessel a first ethylene polymerization catalyst and a first diluent, thereby providing a first catalyst slurry, transferring said first catalyst slurry from said mixing vessel to an ethylene polymerization loop reactor at a concentration suitable for polymerizing ethylene, increasing the ratio of said diluent to said first ethylene polymerization catalyst in said first catalyst slurry, stopping the supply of said first catalyst slurry to said mixing vessel, stopping the supply of said first catalyst slurry to said ethylene polymerization loop reactor, stopping the supply of ethylene to said ethylene polymerization loop reactor, removing said first catalyst slurry from said ethylene polymerization loop reactor, emptying said mixing vessel, optionally rinsing said mixing vessel with fresh diluent, transfe

Abstract: This invention discloses caps and closures produced by injection molding with a bimodal high density polyethylene (HDPE) resin comprising a low molecular weight, high density polyethylene fraction substantially free of comonomer and a high molecular weight, low density polyethylene fraction, having a molecular weight distribution of at least 3.5, preferably greater than 4.0, prepared in two reactors connected in series in the presence of a metallocene-containing catalyst system, wherein the metallocene comprises a bisindenyl or a bis-tetrahydrogenated-indenyl component.

Abstract: A process for manufacturing defined functional lactic acid oligomers can include contacting lactide with at least one compound that is a transfer agent. Oligomers can be prepared according to the process.

Abstract: A method can include immortal ring-opening homopolymerisation of cyclic carbonates or cyclic esters in the presence of a catalytic system, or sequential two-step ring-opening block copolymerisation of one or more cyclic monomers selected from cyclic carbonates or cyclic esters in the presence of the catalytic system. The catalytic system can include a phenolate supported metallic complex. The catalytic system can also include an alcohol or a primary amine containing aliphatic and/or aromatic moieties. The alcohol or primary amine can be present in a molar ratio with respect to the metallic complex that is larger than 1.

Abstract: The invention relates to a process for the preparation of a particulate polyethylene product in a loop reactor, wherein the polymerization catalyst applied in the polymerization process comprises a particulate metallocene-alumoxane catalyst immobilized on a porous silica support; and whereby said metallocene-alumoxane catalyst is heterogeneously distributed on said porous silica support.

Abstract: The present invention relates to the field of tailored di-, tri- and multi-block as well as gradient polyesters/polycarbonates copolymers prepared by introducing monomers simultaneously in the reaction medium in the presence of an organometallic, metal salt or organic catalyst.

Abstract: The invention relates to a process for the preparation of a particulate polyethylene product in a loop reactor, wherein the polymerization catalyst applied in the polymerization process comprises a particulate metallocene-alumoxane catalyst immobilized on a porous silica support; and whereby said metallocene-alumoxane catalyst is heterogeneously distributed on said porous silica support.

Abstract: The present invention relates to a method for producing a catalyst slurry blend suitable for polymerizing ethylene in an ethylene polymerization loop reactor for obtaining an at least trimodal polyethylene product, comprising the steps of: transferring a first ethylene polymerization catalyst at a first mass flow rate to a mixing vessel, simultaneously transferring a second ethylene polymerization catalyst at a second mass flow rate to said mixing vessel, thereby in situ providing a catalyst slurry blend, wherein said second ethylene polymerization catalyst is different from the first ethylene polymerization catalyst, adjusting and monitoring said first and second mass flow rates, thereby obtaining said catalyst slurry blend at a concentration suitable for polymerizing ethylene, and feeding said catalyst slurry blend to an ethylene polymerization double loop reactor producing said at least trimodal polyethylene product.