摘要:
A layered microporous polymeric membrane includes a first blend region having a thickness T1, a third blend region having a thickness T3, and a second blend region located between the first and third blend regions and having a thickness T2, wherein [(T1−T2)/T1]≧0.05 and [(T3−T2)/T3]≧0.05.
摘要:
Provided are methods of producing polymers with broadened molecular weight and/or composition distribution in a continuous homogeneous polymerization system utilizing reactor temperature gradients, reactor polymer concentration gradients, monomer concentration gradients, catalyst concentration gradients, and combinations thereof in the polymerization reactor. Such methods are particularly suitable when utilizing metallocene catalysts and other single-site catalysts, which generally produce polymers with narrow molecular weight and composition distribution.
摘要:
A process for fluid phase in-line blending of plasticized polymers is provided. The process includes providing two or more reactor trains configured in parallel and a separator for product blending and product-feed separation, wherein one or more of the reactor trains produces one or more polymers and one or more of the reactor trains produces one or more plasticizers; contacting in at least one of the parallel reactor trains olefin monomers, catalyst systems, optional comonomers, optional scavengers, and optional diluents or solvents, at a temperature above the solid-fluid phase transition temperature of the polymerization system and a pressure no lower than 10 MPa below the cloud point pressure of the polymerization system and less than 1500 MPa; forming a reactor effluent including a homogeneous fluid phase polymer-monomer mixture and plasticizer-monomer mixture in each parallel reactor train; passing the reactor effluents through the separator; maintaining the temperature and pressure within the separator above the solid-fluid phase transition point but below the cloud point pressure and temperature to form a fluid-fluid two-phase system including a plasticized polymer-rich blend phase and a monomer-rich phase; and separating the monomer-rich phase from the plasticized polymer-rich blend phase. The polymer-rich blend phase is conveyed to a downstream finishing stage for further monomer stripping, drying and/or pelletizing to form a plasticized polymer product blend. Suitable plasticizers for in-line production and blending include polyalphaolefin oligomers, polybutenes, low glass transition temperature polymers and combinations thereof.
摘要:
Embodiments of the present invention relate to article comprising 1) a functionalized component, 2) tackifier, and 3) an olefin polymer comprising one or more C3 to C40 olefins, optionally one or more diolefins, and less than 5 mole % of ethylene having a Dot T-Peel of 1 Newton or more, a branching index (g′) of 0.95 or less measured at the Mz of the polymer; and an Mw of 100,000 or less; where the functional component is selected from the group consisting of functionalized polymers, functionalized oligomers and beta nucleating agents; and where the Gardner color of the adhesive does not change by more than 7 Gardner units when the adhesive has been heat aged at 180° C. for 48 hours as compared to the Gardner color of the unaged composition.
摘要:
A microporous polyolefin membrane comprising a polyethylene resin, and polypropylene having a weight-average molecular weight of 6×105 or more and a heat of fusion of 90 J/g or more (measured by a differential scanning calorimeter), a fraction having a molecular weight of 1.8×106 or more being 10% or more by mass of the polypropylene.
摘要:
Disclosed herein is an in-reactor produced multi-component copolymer comprises a semi-crystalline component having a crystallinity of 20% or more, and an amorphous component having a crystallinity of 5% or less. The copolymer comprises at least 80 wt % of units derived from propylene and from about 1 to about 20 wt % of units derived from at least one C6 to C12 alpha-olefin. The copolymer has a viscosity at 190° C. of at least 530 mPa sec and a heat of fusion between about 10 and about 70 J/g. An adhesive containing the copolymer exhibits a good balance of adhesive properties and mechanical strength.
摘要:
Disclosed herein are adhesives comprising a copolymer comprising at least 80 wt % of units derived from propylene and from about 1 to about 20 wt % of units derived from at least one C6 to C10 alpha-olefin. The copolymer has a molecular weight of less than 100,000 and a heat of fusion between about 10 and about 70 J/g. An adhesive containing the copolymer preferably exhibits at least 50% fiber tear at −18° C. and at least 50% fiber tear at +25° C. using Inland paper board as a substrate; a viscosity of less than 50,000 mPa sec at 190° C., a set time of less than 4 seconds and a toughness of at least 3.4 megajoule/m3.
摘要:
Process to polymerize olefins comprising contacting, in a polymerization system, olefins having three or more carbon atoms with a catalyst compound, activator, optionally comonomer, and optionally diluent or solvent, at a temperature above the cloud point temperature of the polymerization system and a pressure no lower than 10 MPa below the cloud point pressure of the polymerization system, where the polymerization system comprises any comonomer present, any diluent or solvent present, the polymer product, where the olefins having three or more carbon atoms are present at 40 weigh % or more.
摘要:
The invention is directed to a plasticized polypropylene thermoplastic composition comprising a blend of A) from 50 to 99.9 wt % of a thermoplastic polymer derived from polypropylene, optionally with one or more copolymerizable monomer selected from C2-C10 α-olefin or diolefin, said polymer having a melt flow rate (MFR) (ASTM D1238) of from 0.5 to 1000 and a crystallinity by differential scanning calorimetry of from 0 to 70%; B) from 0.1 to 50 wt % of at least one ethylene copolymer having a weight-average molecular weight (Mw) (GPC) of from 500 to 10,000, a molecular weight distribution (MWD) (GPC) of from greater than 1.5 to less than or equal to 3.5, and a comonomer content of from greater than or equal to 20 mol % to less than 70 mol %; and optionally, C) from 0 to 20 wt % of a thermoplastic polypropylene modifier compound other than that of B).
摘要:
This invention relates to olefin polymers particularly suited to satisfying the dielectric properties required in electrical device use. The olefin polymers can be prepared by contacting polymerizable olefin monomers with catalyst complexes of Group 3–11 metal cations and noncoordinating or weakly coordinating anion compounds bound directly to the surfaces of finely divided substrate particles or to polymer chains capable of effective suspension or solvation in polymerization solvents or diluents under solution polymerization conditions. Thus, the invention includes polyolefin products prepared by the invention processes, particularly ethylene-containing copolymers, having insignificant levels of mobile, negatively charged particles as detectable by Time of Flight SIMS.