Patent application number | Description | Published |
20080269441 | Polymerization process providing polyethylene of enhanced optical properties - A process for the polymerization of ethylene to provide an ethylene polymer of reduced Yellowness Index. A feed stream, comprising an inert hydrocarbon diluent containing ethylene in a minor amount, is supplied to a polymerization reactor. A chromium-based polymerization catalyst and a triethylboron co-catalyst are incorporated into the feed stream within the reactor. The polymerization catalyst will normally be used in an amount within the range of 0.008-0.1 wt. % of the diluent in the feed stream and the triethylboron co-catalyst is incorporated in an amount within the range of 0.1-50 ppm of the diluent. The polymer fluff from the reactor is heated to a temperature sufficient to melt the fluff which is then extruded to produce a polymer product. The Yellowness Index after high temperature aging is at least 5% less than the corresponding Yellowness Index of a corresponding polymer product produced without the triethylboron co-catalyst. | 10-30-2008 |
20080275197 | Bimodal Polyethylene Resins That Have High Stiffness and High ESCR - A bimodal polyethylene having a high density ranging from about 0.955 to about 0.959 g/cc, an improved environmental stress cracking resistance (ESCR) of from about 400 to about 2500 hours, and an improved 0.4% flexural modulus of from about 180,000 to about 260,000 psi (1,200 MPa to about 1,800 MPa) may be formed using a Ziegler-Natta polymerization catalyst using two reactors in series. The bimodal polyethylene may have a high load melt index (HLMI) of from about 2 and about 30 dg/min and may be optionally made with a small amount of alpha-olefinic comonomer in the second reactor. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. | 11-06-2008 |
20090023875 | Process for Controlling Morphology of Ziegler-Natta Catalysts - Disclosed is a process for making a Ziegler-Natta catalyst having controlled particle size and distribution. It comprises altering the precipitation of a catalyst component from a catalyst synthesis solution including a soluble magnesium containing catalyst precursor by controlling the concentration of either the soluble magnesium containing catalyst precursor, wherein the average particle size of the catalyst component is increased, and the particle size distribution increased, with a decreased concentration of the soluble magnesium containing catalyst precursor; or of the precipitating agent, wherein the average particle size of the catalyst component is increased, and the particle size distribution increased with an increased concentration of the precipitating agent. Use of the invention enables improved catalyst consistency regardless of production scale and customizing of catalyst morphology to desired polymer morphology. The novel catalyst components may be used to prepare polymers, and end-use articles therefrom, having desirable properties. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. | 01-22-2009 |
20090105433 | Multi-component catalyst systems and polymerization processes for forming in-situ heterophasic copolymers and/or varying the xylene solubles content of polyolefins - Embodiments of the invention generally include multi-component catalyst systems, polymerization processes and heterophasic copolymers formed by the processes. The multi-component catalyst system generally includes a first catalyst component selected from Ziegler-Natta catalyst systems including a diether internal electron donor and a metallocene catalyst represented by the general formula XCp | 04-23-2009 |
20090324911 | Polymeric compositions comprising polylactic acid and methods of making and using same - A multi-component article comprising a first component comprising a biodegradable polymer, and a second component comprising a polyolefin and a reactive modifier. A method of preparing a multi-layer film comprising coextruding first and second film layers, wherein the first layer comprises a polylactic acid and the second layer comprises a polyolefin and an epoxy-functionalized polyolefin. A method of preparing a multi-component fiber comprising coextruding a core component and a sheath component, wherein the core component comprises a polyolefin and an epoxy-functionalized polyolefin and the sheath component comprises a polylactic acid. | 12-31-2009 |
20090326130 | POLYMERIC BLENDS AND METHODS OF USING SAME - A film comprising a polylactic acid and polypropylene blend having a haze of from about 10% to about 95% and a gloss 45° of from about 50 to about 125. A method of producing an oriented film comprising blending polypropylene and polylactic acid to form a polymeric blend, forming the polymeric blend into a film, and orienting the film. A method of producing an injection molded article comprising blending polypropylene and polylactic acid to form a polymeric blend, injecting the polymeric blend into a mold, and forming the article. | 12-31-2009 |
20090326152 | Compatibilized polypropylene and polylactic acid blends and methods of making and using same - A composition comprising a blend of a polyolefin, polylactic acid, and a reactive modifier. A method of producing an oriented film comprising reactive extrusion compounding a mixture comprising polypropylene, polylactic acid, a reactive modifier to form a compatibilized polymeric blend, casting the compatibilized polymeric blend into a film, and orienting the film. A method of preparing a reactive modifier comprising contacting a polyolefin, a multifunctional acrylate comonomer, and an initiator under conditions suitable for the formation of an epoxy-functionalized polyolefin wherein the epoxy-functionalized polyolefin has a grafting yield of from 0.2 wt. % to 15 wt. %. | 12-31-2009 |
20100081746 | Color Reduction in Polyethylene Modified by Radical Initiation - Polyethylene modified by using radical initiators such as oxygen and peroxides sometimes has a yellow color which may be reduced or eliminated by incorporating additives such as polyethylene glycol, and/or neutralizing species such as alkali metal stearates, particularly calcium stearate, and zinc oxide. | 04-01-2010 |
20110269923 | MULTI-COMPONENT CATALYST SYSTEMS AND POLYMERIZATION PROCESSES FOR FORMING IN-SITU HETEROPHASIC COPOLYMERS AND/OR VARYING THE XYLENE SOLUBLES CONTENT OF POLYOLEFINS - Embodiments of the invention generally include multi-component catalyst systems, polymerization processes and heterophasic copolymers formed by the processes. The multi-component catalyst system generally includes a first catalyst component selected from Ziegler-Natta catalyst systems including a diether internal electron donor and a metallocene catalyst represented by the general formula XCp | 11-03-2011 |
20120064268 | Process for Controlling Morphology of Ziegler-Natta Catalysts - Disclosed is a process for making a Ziegler-Natta catalyst having controlled particle size and distribution. The process enables improved catalyst consistency regardless of production scale and customizing of catalyst morphology to desired polymer morphology. The novel catalyst components may be used to prepare polymers, and end-use articles therefrom, having desirable properties. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. | 03-15-2012 |
20120080822 | Compatibilized Polypropylene and Polylactic Acid Blends and Methods of Making and Using Same - A composition comprising a blend of a polyolefin, polylactic acid, and a reactive modifier. A method of producing an oriented film comprising reactive extrusion compounding a mixture comprising polypropylene, polylactic acid, a reactive modifier to form a compatibilized polymeric blend, casting the compatibilized polymeric blend into a film, and orienting the film. A method of preparing a reactive modifier comprising contacting a polyolefin, a multifunctional acrylate comonomer, and an initiator under conditions suitable for the formation of an epoxy-functionalized polyolefin wherein the epoxy-functionalized polyolefin has a grafting yield of from 0.2 wt. % to 15 wt. %. | 04-05-2012 |
20120296044 | Polymeric Blends and Methods of Using Same - A film comprising a polylactic acid and polypropylene blend having a haze of from about 10% to about 95% and a gloss 45° of from about 50 to about 125. A method of producing an oriented film comprising blending polypropylene and polylactic acid to form a polymeric blend, forming the polymeric blend into a film, and orienting the film. A method of producing an injection molded article comprising blending polypropylene and polylactic acid to form a polymeric blend, injecting the polymeric blend into a mold, and forming the article. | 11-22-2012 |
20120296045 | Polymeric Blends and Methods of Using Same - A film comprising a polylactic acid and polypropylene blend having a haze of from about 10% to about 95% and a gloss 45° of from about 50 to about 125. A method of producing an oriented film comprising blending polypropylene and polylactic acid to form a polymeric blend, forming the polymeric blend into a film, and orienting the film. A method of producing an injection molded article comprising blending polypropylene and polylactic acid to form a polymeric blend, injecting the polymeric blend into a mold, and forming the article. | 11-22-2012 |
20130102743 | MULTI-COMPONENT CATALYST SYSTEMS AND POLYMERIZATION PROCESSES FOR FORMING IN-SITU HETEROPHASIC COPOLYMERS AND/OR VARYING THE XYLENE SOLUBLES CONTENT OF POLYOLEFINS - Embodiments of the invention generally include multi-component catalyst systems, polymerization processes and heterophasic copolymers formed by the processes. The multi-component catalyst system generally includes a first catalyst component selected from Ziegler-Natta catalyst systems including a diether internal electron donor and a metallocene catalyst represented by the general formula XCp | 04-25-2013 |
20130197161 | Injection Molded Article Comprising Polypropylene and Polylactic Acid - A film comprising a polylactic acid and polypropylene blend having a haze of from about 10% to about 95% and a gloss 45° of from about 50 to about 125. A method of producing an oriented film comprising blending polypropylene and polylactic acid to form a polymeric blend, forming the polymeric blend into a film, and orienting the film. A method of producing an injection molded article comprising blending polypropylene and polylactic acid to form a polymeric blend, injecting the polymeric blend into a mold, and forming the article. | 08-01-2013 |