摘要:
Propylene-based polymer compositions are provided comprising propylene and from about 5 wt % to about 20 wt % of one or more C2 and/or C4-C12 α-olefins. The polymer compositions have a triad tacticity greater than about 90%, a heat of fusion less than about 75 J/g, and a melt flow rate (MFR) greater than or equal to about 25 g/10 min (230° C., 2.16 kg). Further, the polymer compositions are reactor grade compositions comprising a reactor blend of a first polymer and a second polymer, preferably where both of the first and second polymers are prepared using the same catalyst system. Meltspun nonwoven fabrics, such as meltblown or spunbond fabrics, comprising such polymer compositions are also provided, as well as processes for forming the nonwoven fabrics.
摘要:
Propylene-based polymer compositions are provided comprising propylene and from about 5 wt % to about 20 wt % of one or more C2 and/or C4-C12 α-olefins. The polymer compositions have a triad tacticity greater than about 90%, a heat of fusion less than about 75 J/g, and a melt flow rate (MFR) greater than or equal to about 25 g/10 min (230° C., 2.16 kg). Further, the polymer compositions are reactor grade compositions comprising a reactor blend of a first polymer and a second polymer, preferably where both of the first and second polymers are prepared using the same catalyst system. Meltspun nonwoven fabrics, such as meltblown or spunbond fabrics, comprising such polymer compositions are also provided, as well as processes for forming the nonwoven fabrics.
摘要:
Elastomeric polymer blends and processes for their production are described. Specifically, the polymer blends comprise a first polymer and a second polymer, where the first polymer comprises from about 70 wt % to about 90 wt % units derived from propylene and from about 10 wt % to about 30 wt % units derived from ethylene and/or a C4-C10 alpha-olefin, and the second polymer comprises from about 88 wt % to about 98 wt % units derived from propylene and from about 2 wt % to about 12 wt % units derived from ethylene and/or a C4-C10 alpha-olefin. The elastomeric polymer blends are further characterized by having two or more of the following properties: an overall propylene content of between about 75 wt % and about 90 wt %, a melting point between about 110° C. and about 145° C., a Vicat softening point greater than about 45° C., a tensile stress at 300% strain of less than about 500 psi (3447 kPa), as determined by a stress strain test according to ASTM D412, or an average maximum force for pellet separation of less than about 10 N in an accelerated storage stability test. The polymer blends are produced in a dual reactor process, in which the first polymer and the second polymer are prepared using differing catalyst systems.
摘要:
Elastomeric polymer blends and processes for their production are described. Specifically, the polymer blends comprise a first polymer and a second polymer, where the first polymer comprises from about 70 wt % to about 90 wt % units derived from propylene and from about 10 wt % to about 30 wt % units derived from ethylene and/or a C4-C10 alpha-olefin, and the second polymer comprises from about 88 wt % to about 98 wt % units derived from propylene and from about 2 wt % to about 12 wt % units derived from ethylene and/or a C4-C10 alpha-olefin. The elastomeric polymer blends are further characterized by having two or more of the following properties: an overall propylene content of between about 75 wt % and about 90 wt %, a melting point between about 110° C. and about 145° C., a Vicat softening point greater than about 45° C., a tensile stress at 300% strain of less than about 500 psi (3447 kPa), as determined by a stress strain test according to ASTM D412, or an average maximum force for pellet separation of less than about 10 N in an accelerated storage stability test. The polymer blends are produced in a dual reactor process, in which the first polymer and the second polymer are prepared using differing catalyst systems.
摘要:
Disclosed are rheology modifiers comprising compositionally disperse polymeric compositions and/or crystallinity disperse polymeric compositions that may be useful in modifying the rheological properties of lubrication fluids, and methods for making such compositions. The compositionally disperse polymeric composition are formed from at least two discrete compositions of ethylene copolymers. The crystallinity disperse polymeric composition are formed from ethylene copolymers having at least two discrete values of residual crystallinity.
摘要:
This invention relates to an ethylene copolymer for lubricating oil, comprising: ethylene; at least one alpha-olefin having 3 or more carbon atoms; and at least one vicinally substituted olefin having 2 to 40 carbon atoms, wherein: the copolymer has a weight-average molecular weight (Mw) of about 50,000 to about 500,000; and an intensity ratio of Sαβ to Sαα insertions, as determined by a 13C-NMR spectrum of less than 0.5.
摘要:
Disclosed are polyethylene (“PE”) compositions, articles comprising PE compositions, and methods of making blended PE compositions, wherein the blended composition comprises from about 80 to about 95 weight % of a first PE and from about 5 to about 20 weight % of a second PE. The first PE has a density greater than or equal to about 0.945 g/cc and a MWD greater than about 5. The second PE has a density less than about 0.945 g/cc, a melt index less than about 0.70 g/10 minutes and less than or equal to the melt index of the first PE, a MWD ranging from about 1 to about 5, a weight average molecular weight less than about 400,000, and a CDBI greater than about 50%. The PE composition has an ESCR greater than the ESCR of the first PE.
摘要:
Disclosed are polyethylene (“PE”) compositions, articles comprising PE compositions, and methods of making blended PE compositions, wherein the blended composition comprises from about 80 to about 95 weight % of a first PE and from about 5 to about 20 weight % of a second PE. The first PE has a density greater than or equal to about 0.945 g/cc and a MWD greater than about 5. The second PE has a density less than about 0.945 g/cc, a melt index less than about 0.70 g/10 minutes and less than or equal to the melt index of the first PE, a MWD ranging from about 1 to about 5, a weight average molecular weight less than about 400,000, and a CDBI greater than about 50%. The PE composition has an ESCR greater than the ESCR of the first PE.