摘要:
Novel catalyst compositions comprising three or more transition metals are effective in increasing catalyst efficiency, reducing polydispersity, and increasing uniformity in molecular weight distribution when used in olefin, and particularly, linear low density polyethylene (LLDPE), polymerizations. The resulting polymers may be used to form differentiated products including, for example, films that may exhibit improved optical and mechanical properties.
摘要:
Novel catalyst compositions comprising three or more transition metals are effective in increasing catalyst efficiency, reducing polydispersity, and increasing uniformity in molecular weight distribution when used in olefin, and particularly, linear low density polyethylene (LLDPE), polymerizations. The resulting polymers may be used to form differentiated products including, for example, films that may exhibit improved optical and mechanical properties.
摘要:
This invention relates to modified Ziegler-Natta catalyst systems that have an excellent activity in homo- or co-polymerisation of ethylene and alpha-olefins and are able to produce polymers having reduced molecular weight distribution and improved incorporation of hexene with respect to conventional Ziegler-Natta catalyst systems.
摘要:
A colorable resin particle having an outer shell of a non-sticky polymer and an inner core of a sticky polymer produced in a gas phase fluidized bed reactor at or above the sticking temperature of the sticky polymer using a non-sticky prepolymerized catalyst and processes for producing the colorable resin and the non-sticky prepolymerized catalyst.
摘要:
Polyolefins exhibiting better particle properties are prepared by polymerizing an olefin or olefins in the presence of a catalyst comprising a solid catalyst component and an organometallic compound, the solid catalyst component being prepared by reacting the following components [I] and [II] at first and then reacting the reaction product thus obtained with the following component [III]:[I] a reaction product obtained by reacting:(1) a silicon oxide and/or an aluminum oxide, and(2) a titanium compound, or a titanium compound and a vanadium compound,[II] a reaction product obtained by the reaction of:(1) a magnesium halide,(2) a compound represented by the general formula Me(OR).sub.n X.sub.z-n wherein Me represents an element of J Groups I to IV in the Periodic Table, z represents the valence of the element Me, n is 0
摘要:
A solid catalyst component for the polymerization of ethylene and the copolymerization of ethylene with C.sub.3 -C.sub.10 alpha-olefins, contains titanium, vanadium and chlorine, is substantially definable by the formula (in atomic proportions):V (1), Ti (n), Cl (4n)where n varies from 1 to 3, and is prepared by reacting titanium tetrachloride with a vanadium arene [V.degree.(arene).sub.2 ] (arene=benzene or mono-, di- or tri-alkyl substituted benzene) in accordance with the equation:V.degree.(arene).sub.2 +nTiCl.sub.4 .fwdarw.VTi.sub.n Cl.sub.4n +2 arenepossibly followed by treatment with an alkyl aluminum chloride. This catalyst component, when associated with a trialkyl aluminium, is highly active in the production of ethylene polymers and copolymers by low temperature, low pressure methods in suspension, or by high temperature, high pressure methods conducted in a tubular reactor or pressure vessel, or by high temperature methods conducted in solution.
摘要:
A heterogeneous procatalyst includes a titanium species, a magnesium chloride component, and a chlorinating agent having a structure A(Cl)x(R1)3-x, where A is aluminum or boron, R1 is a (C1-C30) hydrocarbyl, and x is 1, 2, or 3. The magnesium chloride component may be thermally treated at a temperature greater than 100 C for at least 30 minutes before or after introduction of the chlorinating agent and titanium species to the heterogeneous procatalyst. The heterogeneous procatalyst having the thermally treated magnesium chloride exhibits improved average molecular weight capability. Processes for producing the heterogeneous procatalyst and processes for producing ethylene-based polymers utilizing the heterogeneous procatalyst are also disclosed.
摘要:
Multi-stage polymerization process for the production of a multi-modal linear low density polyethylene in at least two staged reactors connected in series comprising at least (i) polymerizing in a first slurry phase stage ethylene monomers and optionally one or more alpha-olefin comonomers, in the presence of a Ziegler-Natta polymerization catalyst system to obtain a first polyethylene fraction component (A) (ii) polymerizing in a second gas or slurry phase stage ethylene monomers and one or more alpha-olefine comonomers, in the presence of a Ziegler-Natta polymerization catalyst system to obtain a second polyethylene fraction component (B), whereby the Ziegler-Natta polymerization catalyst system comprises: 1) a solid procatalyst formed by contacting at least: a) a Mg-alcoholate complex of the formula (I): Mg(OR1)2-n(R1)n, wherein each R1 independently represents a C1-C20 hydrocarbyl group and 0
摘要:
Novel metal complexes, particularly chromium complexes, which contain at least one tridentate ligand are disclosed and prepared. Olefins, particularly ethylene, can be reacted to form butene and/or other homo- or co-oligomers and/or polymers with high α-olefin concentrations by contacting a metal catalyst which contains a transition metal, particularly chromium, complexes having per metal atom at least one tridentate ligand with N, O, or N and O coordinating sites.
摘要:
Olefin is polymerized using a catalyst comprising a solid catalyst component and an organometallic compound, the solid catalyst component being prepared by reacting 1 a reaction product obtained by reacting the reaction product of Si oxide and/or Al oxide and Ti compound or both Ti compound and V compound (Ti.V component) with organic Al compound, with 2 a reaction product obtained by the reaction of Mg halide, a compound of the general formula Me(OR).sub.n X.sub.z-n and Ti.V component (optional component), and further reacting the reaction product of the above 1 and 2 with 3 a compound of the general formula R.sub.p Si(OR).sub.q X.sub.4-p-q.