摘要:
Polymerization processes in a bulk loop reactor are described herein. In particular, a method of contacting a flow of metallocene with a flow of propylene is provided. This method includes directing the flow of metallocene towards a junction, directing the flow of propylene towards the junction and maintaining a portion of the flow of metallocene separate from a portion of the flow propylene within a portion of the junction downstream of the flow of propylene into the junction. In another embodiment, a method of introducing a quantity of antifouling agent into a catalyst mixing system is provided. In this embodiment a portion of the antifouling agent is introduced at or downstream of a point of contact of a stream of propylene with a stream of catalyst. The antifouling agent may be a member, alone or in combination with other members, selected from Stadis 450 Conductivity Improver, Synperonic antifouling agent, and Pluronic antifouling agent.
摘要:
Injection stretch blow molded (ISBM) articles containing a bio-based polymers and methods of forming the same are described herein. The method generally includes providing a propylene-based polymer; contacting the propylene-based polymer with polylactic acid to form a polymeric blend; injection molding the blend into a preform; and stretch-blowing the preform into an article.
摘要:
Polymeric compositions and processes of forming the same are discussed herein. The processes generally include contacting a polylactic acid with a reactive modifier selected from epoxy-functionalized polybutadiene, ionic monomer, and combinations thereof.
摘要:
Methods of forming polyolefins and catalysts are described herein. Such methods generally include forming Ziegler-Natta catalyst compounds in the absence of one or more blended compounds typically used to form such catalyst.
摘要:
Method employing a supported metallocene catalyst composition in the production of an isotactic ethylene propylene co-polymer. The composition comprises a metallocene component supported on a particulate silica support having average particle size of 10-40 microns, a pore volume of 1.3-1.6 ml/g, a surface area of 200-400 m 2/g. An alkylalumoxane cocatalyst component is incorporated on the support. The isospecific metallocene is characterized by the formula: B(CpRaRb)(FlR′2)MQn (1) or by the formula: B′(Cp′R′aR′b)(Fl′)M′Q′n′ (2) In the formulas Cp and Cp′ are substituted cyclopentadienyl groups, Fl and Fl′ are fluorenyl groups, and B and B′ are structural bridges. R′ are substituents at the 2 and 7 positions, Ra and R′a are substituents distal to the bridge, and Rb and R′b are proximal to the bridge. M and M′ are transition metals, Q′ is a halogen or a C1-C4 alkyl group; and n′ is an integer of from 0-4.
摘要:
Disclosed is a method of polymerizing olefin using a compatible combination of a multi-site catalyst and a single-site catalyst. The catalysts may be a Ziegler-Natta catalyst and a metallocene catalyst. The resulting polymer, which may be a homopolymer or a random copolymer, may exhibit a molecular weight distribution which is intermediate than that resulting for polymers prepared using either catalyst alone.
摘要:
Supported stereospecific catalysts and processes for the stereotactic propagation of a polymer chain derived from ethylenically unsaturated monomers such as the polymerization of propylene to produce syndiotactic polypropylene or isotactic polypropylene. The supported catalyst comprises a stereospecific metallocene catalyst component and a co-catalyst component comprising an alkylalumoxane. Both the metallocene catalyst component and the co-catalyst component are supported on a particulate polyorganosilsesquioxane support comprising spheroidal particles of a polyorganosilsesquioxane having an average. diameter with the range of 0.3-20 microns. The polyorganosilsesquioxane support is characterized by relatively low surface area, specifically a surface area less than 100 square meters per gram. The metallocene component can take the form of a single metallocene or two or more metallocenes which are co-supported on the polyorganosilsesquioxane support.
摘要:
Catalyst Systems, processes of forming the same and polymers and polymerization processes are described herein. The process of forming the catalyst system generally includes providing a first compound including a magnesium dialkoxide and aluminum alkoxide: contacting the first compound with a first agent and a second agent to form a solution of reaction product “A”, the first agent including a titanating agent and the second agent including a first metal halide; contacting the solution of reaction product “A” with a third agent to form a solid reaction product “B”, the third agent including a second metal halide: contacting the solid reaction product “B” with a fourth agent to form a solid reaction product “C”, the fourth agent including a third metal halide: optionally contacting the solid reaction product “C” with a fifth agent to form a solid reaction product “D”, the fifth agent including a fourth metal halide; and contacting the solid reaction product “C” or “D” with a sixth agent to form a catalyst component, the sixth agent including a first organoaluminum compound.
摘要:
Method employing a supported metallocene catalyst composition in the production of an isotactic ethylene propylene co-polymer. The composition comprises a metallocene component supported on a particulate silica support having average particle size of 10-40 microns, a pore volume of 1.3-1.6 ml/g, a surface area of 200-400 m2/g. An alkylalumoxane cocatalyst component is incorporated on the support. The isospecific metallocene is characterized by the formula: B(CpRaRb)(FlR′2)MQn (1) or by the formula: B′(Cp′R′aR′b)(Fl′)M′Q′n′ (2) In the formulas Cp and Cp′ are substituted cyclopentadienyl groups, Fl and Fl′ are fluorenyl groups, and B and B′ are structural bridges. R′ are substituents at the 2 and 7 positions, Ra and R′a are substituents distal to the bridge, and Rb and R′b are proximal to the bridge. M and M′ are transition metals, Q′ is a halogen or a C1-C4 alkyl group; and n′ is an integer of from 0-4.