摘要:
A catalyst component formed by the steps of contacting a transition metal-containing metallocene of a transition metal of Group 4, 5 or 6 of the Periodic Table of the Elements with silica or an organic support. This product is contacted with an organomagnesium compound or complex followed by contact with an alcohol and a silane. Finally, the so-contacted product is contacted with a Group 4, 5 or. 6 transition metal-containing non-metallocene compound. The component is preferably combined with an aluminum-containing cocatalyst to form a catalyst system.
摘要:
A unimodal polymeric resin having a density of from about 0.946 g/ml to about 0.97 g/ml and a zero shear viscosity of from about 8×102 Pa-s to about 6×104 Pa-s. A method comprising (a) providing a catalyst system comprising a half-sandwich transition metal complex; (b) contacting the catalyst system with an olefin under conditions suitable to form a polyolefin, wherein the polyolefin is unimodal; and (c) recovering the polyolefin, wherein the polyolefin has a density of from about 0.946 g/ml to about 0.97 g/ml and a zero shear viscosity of from about 8×102 Pa-s to about 6×104 Pa-s. A unimodal polymeric resin having a density of from about 0.946 g/ml to about 0.97 g/ml and a CY-a parameter of from about 0.5 to about 0.6.
摘要:
Methods of controlling polymerization reactions using a synergistic amount of hydrogen and an organozinc compound are disclosed. The resulting polymers have lower molecular weights and higher melt flow indices.
摘要:
A catalyst system comprising a half-sandwich chromium complex, an activator support and an optional cocatalyst. A compound of formula Cp′Cr(Cl)2(Ln), where Cp′ is η5—C5H4CH2CH2CH═CH2 and Ln is pyridine, THF or diethylether. A compound of formula Cp″Cr(Cl)2(Ln), where Cp″ is η5—C5H4C(Me)2CH2CH2CH═CH2 and Ln is pyridine, THF or diethylether.
摘要:
Methods for removing polymer skins or build-up from reactor walls in polymerization reactor systems containing a loop slurry reactor are disclosed. Such methods can employ removing some or all of the comonomer from the reactor system in combination with increasing the polymerization temperature of the loop slurry reactor.
摘要:
This disclosure provides for olefin wax oligomer compositions, methods of producing olefin wax oligomer composition, and methods for oligomerizing olefin waxes. This disclosure encompasses metallocene-based olefin wax oligomerization catalyst systems, including those that include a metallocene and an aluminoxane, a metallocene and a solid oxide chemically-treated with an electron withdrawing anion, and a metallocene, a solid oxide chemically-treated with an electron withdrawing anion, and an organoaluminum compound. The olefin wax oligomers prepared with these catalyst systems can decreased needle penetrations, increased viscosity, and an increased drop melt, making them useful as an additive in candles, stone polishes, liquid polishes, and mold release formulations.
摘要:
This invention relates to the field of olefin polymerization catalyst compositions, and methods for the polymerization and copolymerization of olefins, including polymerization methods using a catalyst composition. One aspect of this invention is the formation and use of a catalyst composition comprising a transition metal compound and an activator for olefin polymerization processes.
摘要:
A new catalyst useful in the polymerization of at least one olefin is disclosed. The catalyst comprises the product obtained by contacting silica, in random order, with (1) at least one hydrocarbon soluble magnesium-containing compound; and (2) a first modifying compound selected from the group consisting of silicon halides, boron halides, aluminum halides and mixtures thereof followed by a second modifying compound selected from the group consisting of halides having the structural formula SiH.sub.r X.sup.2.sub.s, where X.sup.2 is halogen; r is an integer of 1 to 3; and s is an integer of 1 to 3 with the proviso that the sum of r and s is 4, a hydrogen halide and mixtures thereof. The product of this step is contacted with a first titanium-containing compound having the structural formula Ti(OR).sub.m X.sub.n, where R is hydrocarbyl or cresyl; X is halogen; m is an integer of 1 to 4; and n is 0 or an integer of 1 to 3, with the proviso that the sum of m and n is 4. Finally, the product of this latter step is, in turn, contacted with a second titanium-containing compound, different from the first titanium-containing compound, having the structural formula TiX.sup.1.sub.p (OR).sup.1).sub.q, where X.sup.1 is halogen; R.sup.1 is hydrocarbyl; p is an integer of 1 to 4; and q is 0 or an integer of 1 to 3, with the proviso that the sum of p and q is 4.A catalyst system comprising the above catalyst, an aluminum-containing first cocatalyst and at least one silane second cocatalyst is also set forth.Finally, a process for polymerizing at least one olefin utilizing the catalyst system of this disclosure is taught.
摘要:
An olefin polymerization catalyst prepared by reacting water with a magnesium dihalide in the presence of a phase transfer catalyst and reacting the resulting hydrated magnesium dihalide with reactants including a benzoic acid ester, an alkoxytitanium compound, an organoaluminum halide and a titanium halide.
摘要:
Methods for removing polymer skins or build-up from reactor walls in polymerization reactor systems containing a loop slurry reactor are disclosed. Such methods can employ removing some or all of the comonomer from the reactor system in combination with increasing the polymerization temperature of the loop slurry reactor.