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:
Reactor designs and processes for operating such reactor designs to minimize or eliminate fouling in homogeneous polymerization processes (solution and supercritical). The process includes providing a reactor with one or more feed entry ports, wherein the reactor feed components are fed through each of the one or more feed entry ports at a linear velocity of greater than or equal to 0.3 m/min. The one or more feed entry ports may also be optionally extended beyond the interior reactor wall by greater than or equal to 2% of the internal radius of the reactor to further decrease the propensity for fouling. A stirred reactor may also include a stirrer feed port for purging the stirrer with a stirrer purge stream at a linear velocity of greater than or equal to 0.3 m/min to decrease stirrer fouling.
摘要:
Reactor designs and processes for operating such reactor designs to minimize or eliminate fouling in homogeneous polymerization processes (solution and supercritical). The process includes providing a reactor with one or more feed entry ports, wherein the reactor feed components are fed through each of the one or more feed entry ports at a linear velocity of greater than or equal to 0.3 m/min. The one or more feed entry ports may also be optionally extended beyond the interior reactor wall by greater than or equal to 2% of the internal radius of the reactor to further decrease the propensity for fouling. A stirred reactor may also include a stirrer feed port for purging the stirrer with a stirrer purge stream at a linear velocity of greater than or equal to 0.3 m/min to decrease stirrer fouling.
摘要:
Provided are elastic propylene-alpha olefin blocky copolymers. In one form, the elastic propylene-alpha olefin blocky copolymer includes an α-olefin content from 12 to 25 wt % and having a propylene crystallinity less than 30 J/g, a Tm −45° C., wherein said copolymer has blocky propylene segments with r1r2 greater than 1.5, and a process for producing such copolymer.
摘要:
Provided are elastic propylene-alpha olefin blocky copolymers. In one form, the elastic propylene-alpha olefin blocky copolymer includes an α-olefin content from 12 to 25 wt % and having a propylene crystallinity less than 30 J/g, a Tm −45° C., wherein said copolymer has blocky propylene segments with r1r2 greater than 1.5, and a process for producing such copolymer.
摘要:
Provided is a heat-seal resin. The resin includes 5 wt % to 95 wt % of a first copolymer and 95 wt % to 5 wt % of a second copolymer based on the total weight of the resin. The first copolymer and the second copolymer together are 90 wt % or more of the total weight of the resin. The first copolymer includes a first monomer of an alphaolefin of 2 to 4 carbon atoms and a second monomer selected from a second monomer of an alphaolefin of 2 to 8 carbon atoms. The first monomer and the second monomer of the first copolymer are different. The first copolymer has an MFR of from 5 to 1000 g/10 minutes and a Tfm of 66° C. to 80° C. The second copolymer includes a first monomer of an alphaolefin of 2 to 4 carbon atoms and a second monomer selected from a second monomer of an alphaolefin of 2 to 8 carbon atoms. The first monomer and the second monomer of the second copolymer are different. The second copolymer has an MFR of from 0.5 to 5 g/10 minutes and a Tfm of 45° C. to 66° C., wherein the first copolymer has an MFR of at least 2 g/10 minutes greater and a Tfm of at least 10° C. greater than the second copolymer. There is also a package formed partly or entirely of the resin.
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:
This invention relates to processes for producing an isotactic propylene homopolymer having more than 15 and less than 100 regio defects (sum of 2,1-erythro and 2,1-threo insertions and 3,1-isomerizations) per 10,000 propylene units; a weight-averaged molecular weight of 35000 g/mol or more; a peak melting temperature of greater than 149° C.; an mmmm pentad fraction of 0.85 or more; a heat of fusion of 80 J/g or more; and a peak melting temperature minus peak crystallization temperature (Tmp−Tcp) of less than or equal to (0.907 times Tmp) minus 99.64 (Tmp−Tcp
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.