摘要:
A polymer having a long chain branching content peaking at greater than about 20 long chain branches per million carbon atoms, and a polydispersity index of greater than about 10 wherein the long chain branching decreases to approximately zero at the higher molecular weight portion of the molecular weight distribution. A polymer having a long chain branching content peaking at greater than about 8 long chain branches per million carbon atoms, a polydispersity index of greater than about 20 wherein the long chain branching decreases to approximately zero at the higher molecular weight portion of the molecular weight distribution. A polymer having a long chain branching content peaking at greater than about 1 long chain branches per chain, and a polydispersity index of greater than about 10 wherein the long chain branching decreases to approximately zero at the higher molecular weight portion of the molecular weight distribution.
摘要:
A method comprising (a) contacting a support and a chromium-containing compound to form chromium-containing support, (b) heat treating the chromium-containing support in an oxidizing atmosphere to form a treated support, (c) contacting the treated support with carbon monoxide to form a CO-contacted support, and (d) contacting the CO-contacted support with hydrogen to form a catalyst. A method comprising oxidizing a chromium-treated support to form a polymerization catalyst, contacting the polymerization catalyst with carbon monoxide to form a reduced polymerization catalyst, contacting the reduced polymerization catalyst with hydrogen to form an activated polymerization catalyst, and contacting the activated polymerization catalyst with ethylene in a reaction zone under suitable reaction conditions to form a random copolymer. A method comprising reducing a polymerization catalyst comprising Cr(VI) to form a polymerization catalyst comprising Cr(II), and treating the polymerization catalyst comprising Cr(II) with hydrogen.
摘要:
A method of preparing a catalyst comprising contacting an acidic colloidal silica suspension with a titanium-containing compound to form a mixture, adjusting the pH of mixture to about neutral to form a catalyst support, and contacting the catalyst support with chromium-containing compound to from a chromium-supported catalyst. A catalyst support prepared by contacting a colloidal silica suspension and a titanium-containing compound under acidic conditions to form a mixture, and contacting the mixture with a basic material in an amount sufficient to increase the pH of the mixture to about 7.
摘要:
A composition comprising a polyethylene wherein the composition is enriched in polymer molecules having topological variations by an enrichment factor ω and wherein the composition displays a long chain branching frequency of greater than about 0.5 long chain branches per 1000 total carbon atoms. A composition comprising an isolated Ziegler-catalyzed polyethylene having a long chain branching frequency of greater than about 0.5 long chain branches per 1000 total carbon atoms at the high molecular weight end.
摘要:
A polymer having a density of from about 0.960 g/cc to about 0.965 g/cc and a melt index of from about 0.2 g/10 min. to about 0.6 g/10 min. wherein an article formed from the polymer has an environmental stress crack resistance of equal to or greater than about 150 hours when measured in accordance with ASTM D 1693 condition B, 100% Igepal. A polymer having a density of from about 0.955 g/cc to about 0.960 g/cc and a melt index of from about 0.2 g/10 min. to about 0.6 g/10 min. wherein an article formed from the polymer has an environmental stress crack resistance of equal to or greater than about 500 hours when measured in accordance with ASTM D 1693 condition B, 100% Igepal.
摘要:
A polymeric resin having a lower molecular weight (LMW) component and a higher molecular weight (HMW) component and the resin having a density of from about 0.955 g/cc to about 0.967 g/cc, a melt index of from about 0.5 dg/min to about 4.0 dg/min, and a zero shear viscosity of from about 3.0×103 Pa-s to about 4.0×104 Pa-s. A method comprising providing a catalyst system comprising at least one transition metal complex, an activator support, and a cocatalyst; contacting the catalyst system with an olefin under conditions suitable to form a polyolefin, wherein the polyolefin has a HMW component and a LMW component; and recovering the polyolefin, wherein the polyolefin has a melt index of from about 0.5 dg/min to about 4.0 dg/min, and a zero shear viscosity of from about 3.0×103 Pa-s to about 4.0×104 Pa-s.
摘要:
A method comprising contacting an olefin in the presence of a catalyst and a melt index modifier (MIM) under conditions suitable to form a polyolefin and recovering the polyolefin, wherein the polyolefin melt index is increased by at least about 25%, wherein the normalized catalyst activity is decreased by less than about 10%, and wherein the MIM is characterized by the general formula R1—HC═CH—R2 or R3R4C═CH2 where R1, R2, R3, R4 are each selected from the group consisting of a non-aromatic organyl group.
摘要翻译:一种方法,包括在适于形成聚烯烃和回收聚烯烃的条件下,在催化剂和熔体指数调节剂(MIM)存在下使烯烃接触,其中聚烯烃熔体指数增加至少约25%,其中归一化催化剂 活性降低小于约10%,其中MIM的特征在于通式为R 1 -H HC = CH-R 2或R 3 R 4C≡CH2,其中R 1,R 2,R 3,R 4各自选自非 - 芳香族有机基团。
摘要:
Methods and systems for preparing catalyst, such as chromium catalysts, are provided. The valence of at least a portion of the catalyst sent to an activator is changed from Cr(III) to Cr(VI). The catalyst is prepared or activated continuously using a fluidization bed catalyst activator.
摘要:
A catalyst composition comprising (a) a first metallocene complex represented by the general formula: where M1 is Ti, Zr or Hf, X1 and X2 are each independently F, Cl, Br, I, methyl, benzyl, phenyl, H, BH4, a hydrocarbyloxide group having up to 20 carbon atoms, a hydrocarbylamino group having up to 20 carbon atoms, a trihydrocarbylsilyl group having up to 20 carbon atoms, OBR′2 wherein R′ may be an alkyl group having up to 12 carbon atoms or an aryl group having up to 12 carbon atoms, and SO3R″ wherein R″ may be an alkyl group having up to 12 carbon atoms or an aryl group having up to 12 carbon atoms, and Cp1 and Cp2 are each independently a substituted or unsubstituted cyclopentadienyl group, or a substituted or unsubstituted indenyl group, where any substituent on Cp1 and Cp2 is H, a hydrocarbyl group having up to 18 carbon atoms or a hydrocarbylsilyl group having up to 18 carbon atoms, (b) a second metallocene complex, (c) a non-group 4 metallocene transition-metal complex, (d) an activator or activator-support, and (e) an optional cocatalyst.