Abstract: Polymeric fibers and nonwoven polymeric fabrics having improved softness characteristics are provided. The fibers and fabrics include either a random propylene copolymer or a blend of a polypropylene polymer and a low-density polyethylene polymer. The random propylene copolymer is produced through metallocene-catalyzed and Z-N polymerization and includes from 80 wt. % to 98 wt. % of propylene-derived units and from 2 wt. % to 20 wt. % ethylene-derived units. The low-density polyethylene polymer is also produced through metallocene-catalyzed polymerization and has a melt index of greater than 10 and a molecular weight distribution of 1.5 to 4. The fibers may be produced using a variety of processes including melt blowing, melt spinning, and spunbonding. The fibers may be converted into nonwoven fabrics through conventional techniques.

Abstract: A blended polypropylene composition, fiber, and nonwoven articles made therefrom are provided. In one aspect, the blended polypropylene composition comprises a first polymer component having a molecular weight distribution of from 2.5 to 8, and a second polymer component having a molecular weight distribution of from 1.8 to 3. The first polymer component has a melt flow rate of greater than 30 g/10 min. and the second polymer component has a melt flow rate of less than 40 g/10 min., and the blended polypropylene composition has a melt flow rate of greater than 5 g/10 min.

Abstract: A method of lowering MFR response of a high melt flow rate polymer producing metallocene catalyst is provided. The method includes contacting the metallocene catalyst with a sufficient quantity of ?,?-diene monomer such that when the catalyst composition is contacted with polymerizable reactants under suitable polymerization conditions, the resulting polymer has an MFR rate in the range of 0.1 to 19. Hydrogen and ethylene may also be present in the polymerization. Additionally a catalyst composition is provided which includes a high melt flow rate polymer producing metallocene catalyst and a sufficient quantity of ?,?-diene monomers such that when the catalyst composition is contacted with a monomer under polymerization conditions, the resulting polymer has an MFR rate in the range of 0.1 to 19.

Abstract: This invention relates to metallocene compositions and their use in the preparation of catalyst systems for olefin polymerization, particularly propylene polymerization. The metallocene compositions may be represented by the formula: wherein R3 are identical or different and are each a halogen atom, a C1-C10 alkyl group which may be halogenated, a C6-C10 aryl group which may be halogenated, a C2-C10 alkenyl group, a C7-C40-arylalkyl group, a C7-C40 alkylaryl group, a C8-C40 arylalkenyl group, a —NR?2, —SR?, —OR?, —OSiR?3 or —PR?2 radical, wherein R? is one of a halogen atom, a C1-C10 alkyl group, or a C6-C10 aryl group, and R9 and R11 are identical or different and are a Group 14 radical having from 1 to 20 carbon atoms or are each primary, secondary or tertiary butyl groups, aryl groups, isopropyl groups, fluoroalkyl groups, trialkyl silyl groups, or other groups of similar size.

Abstract: This invention relates to bridged indenyl metallocene compositions and their use in the preparation of catalyst systems for olefin polymerization, particularly propylene polymerization. The bridge may be represented by the formula: wherein: R17 to R24 are identical or different, and are one of a hydrogen atom, a C1-C10 alkyl group, a C1-C10 alkoxy group, a C6-C10 aryl group, a C6-C10 aryloxy group, a C2-C10 alkenyl group, a C7-C40 arylalkyl group, a C7-C40 alkylaryl group, a C8-C40 arylalkenyl group, or a halogen atom, or together are a conjugated diene which is optionally substituted with one or more hydrocarbyl, tri(hydrocarbyl)silyl groups or hydrocarbyl, tri(hydrocarbyl)silylhydrocarbyl groups, said diene having up to 30 atoms not counting hydrogen; or two or more adjacent radicals R17 to R24, including R20 and R21, together with the atoms connecting them form one or more rings; and M2 is carbon, silicon, germanium or tin.

Abstract: Propylene ethylene copolymers with an ethylene content between 8 and 32 mole % have been grafted with maleic anhydride and a peroxide. The functionality level is higher than what is reported with polypropylene.

Abstract: Olefin polymerization processes using catalyst systems based on metallocenes and olefin, in particular, propylene polymers obtainable thereby. The metallocenes may be represented by the formula: ? wherein M1 preferably is zirconium or hafnium; and R12 is different from hydrogen.

Abstract: The invention generally relates to thermoplastic blends having improved properties. Optionally, these blends may be dynamically vulcanized. More specifically, this invention is directed to a composition comprising a blend of chloromethylated(styrene-isobutylene) polymer and a thermoplastic resin selected from the group consisting of polyamides, polyesters, polycarbonates, polysulfones, polyacetals, polyacetones, acrylonitrile-butadiene styrene resins, polyphenylene oxide, polyphenylene sulfide, styrene-acrylonitrile resins, styrene-maleic anhydride resins, polyamides, aromatic polyketones, ethylene vinyl alcohol polymer and mixtures thereof. Tires and tire components such as air permeation prevention films comprising these compositions are also provided.

Abstract: This invention relates to metallocene compositions and their use in the preparation of catalyst systems for olefin polymerization, particularly propylene polymerization. The metallocene compositions may be represented by the formula: wherein R9 and R11 are identical or different and are a Group 14 radical having from 1 to 20 carbon atoms or are each primary, secondary or tertiary butyl groups, aryl groups, isopropyl groups, fluoroalkyl groups, trialkyl silyl groups, or other groups of similar size.

Abstract: An olefin polymerization catalyst system, comprising a catalyst represented by the general formula CrR4, wherein each R is independently a hydrocarbyl or substituted hydrocarbyl, with the proviso that R may not be a cyclopentadienyl group, an activator represented by the general formula, MQ2, where M is a Group II metal, where each Q is independently an alkyl, or substituted alkyl; and a support. The support may be organic or inorganic. Ethylene and one or more olefins may be polymerized by the catalyst system.

Abstract: This invention relates generally to crystalline polypropylene polymers and methods for their production. Specifically, this invention relates to crystalline polypropylene polymer compositions comprising both propylene homopolymers and propylene copolymers. The compositions are prepared using metallocene catalyst systems comprising at least two metallocenes in a polymerization process that involves the sequential or parallel polymerization of propylene homopolymers and copolymers using propylene with a small amount of comonomer, preferably ethylene. The resulting polymers are excellent for use in the production of biaxially oriented films. Films prepared with these propylene polymers have a significantly broader processability range and can be evenly stretched at lower temperature compared to films prepared from traditional polypropylene polymers.

Abstract: This invention relates to propylene homopolymer compositions obtained from metallocene catalysis wherein the polymer has a molecular weight distribution (Mw/Mn) in the range of from 4.0 to 20.0. The propylene homopolymer composition may be prepared in a multiple stage polymerization process using the same metallocene component in at least two stages. The composition may comprise isotactic homopolymer in one embodiment, and have a hexane extractables of less than 2 wt % in one embodiment. The composition is useful in making films.

Abstract: This invention relates to compositions derived from polyolefins combined with a polymeric nucleating agent. The nucleating agent is specifically a diene-propylene copolymer.

Abstract: The present invention provides a catalyst system that exhibits unexpected control of desired properties in polyolefin products. The catalyst system includes a titanium-supported catalyst in combination with a mixture of tetraethoxysilane (TEOS) and dicyclopentyldimethoxy-silane (DCPMS). This catalyst system has been found to be effective in making polypropylene and polypropylene copolymers having relatively high melt flow rates and moderately broad molecular weight distribution.

Abstract: This invention relates to metallocene catalyst compositions which are highly active for the polymerization of olefins, particularly prochiral &agr;-olefins. The catalyst compositions contain at least one metallocene, and least one activator and a support that has been fluorided using a fluoride containing compound.

Abstract: This invention relates to metallocene catalyst compositions which are highly active for the polymerization of olefins, particularly prochiral &agr;-olefins. The catalyst compositions contain at least one metallocene, and least one activator and a support that has been fluorided using a fluoride containing compound.

Abstract: Improved thermoplastic polymer blend compositions comprising an isotactic polypropylene component and an alpha-olefin and propylene copolymer component, said copolymer comprising crystallizable alpha-olefin sequences. In a preferred embodiment, improved thermoplastic polymer blends are provided comprising from about 35% to about 85% isotactic polypropylene and from about 30% to about 70% of an ethylene and propylene copolymer, wherein said copolymer comprises isotactically crystallizable propylene sequences and is predominately propylene. The resultant blends manifest unexpected compatibility characteristics, increased tensile strength, and improved process characteristics, e.g., a single melting point.

Abstract: Described are certain monocyclopentadienyl Group IV B metal compounds, catalyst systems comprising such monocyclopentadienyl metal compounds and an activator, and a process using such catalyst systems for the production of polyolefins, particularly high molecular weight ethylene-&agr;-olefin copolymers having a high level of &agr;-olefin incorporation.

Abstract: This invention is generally directed toward a supported catalyst system useful for polymerizing olefins. The method for supporting the catalyst of the invention provides for a supported metallocene catalyst formed by vacuum or pressurized impregnation.

Abstract: This invention relates generally to crystalline propylene polymers, to methods for their production and to methods for their use in film applications. Specifically, this invention relates to crystalline propylene polymers comprising both propylene homopolymer and propylene copolymer. The compositions are prepared using metallocene catalyst systems comprising at least two metallocenes in a polymerization process that involves the sequential or parallel polymerization of propylene homopolymer and copolymer using propylene with a small amount of comonomer, preferably ethylene. The polymerization is catalyzed by a dual metallocene catalyst system. The resulting polymers have a broad, bimodal molecular weight distribution. The resulting polymers are excellent for use in the production of biaxially oriented films or non-oriented films.