摘要:
Group 4 metal complexes comprising a polyvalent, heteroaryl donor ligand and their use as components of olefin polymerization catalysts, especially suited for preparing propylene copolymer products having high isotacticity and low molecular weight, are disclosed.
摘要:
Two or more chemically distinguishable ethylenically unsaturated polymers, at least one having from 0.001 to 50 mole percent unsaturation and at least one other having an expected Tg or measured Tm value greater than 100° C. are cross-metathesized to form thermoplastic elastomers having improved performance properties.
摘要:
A combinatorial method for identifying a catalyst composition for use in the homogeneous addition polymerization of an olefin monomers, said catalyst composition comprising a transition metal compound, a cocatalyst and a polymerization modifier, as well as catalyst compositions and improved olefin polymerization processes resulting therefrom.
摘要:
A cross-metathesized product mixture is prepared by contacting a metathesis catalyst under metathesis conditions with a composition comprising two or more chemically distinguishable ethylenically unsaturated polymers, at least one of said ethylenically unsaturated polymers (first polymer) having from 0.001 to 50 mole percent unsaturation and at least one other of said ethylenically unsaturated polymers (second polymer) being an amorphous polymer having a Tg less than 0° C. and having from 0.001 to 5 mole percent unsaturation.
摘要:
A supported catalyst composition and process for preparing high molecular weight polymers of one or more addition polymerizable monomers, especially propylene, said composition comprising: 1) a substrate comprising the reaction product of a solid, particulated, high surface area, metal oxide, metalloid oxide, or a mixture thereof and an organoaluminum compound, 2) a Group 4 metal complex of a polyvalent, Lewis base ligand; and optionally, 3) an activating cocatalyst for the metal complex.
摘要:
Group 4 metal complexes comprising a polyvalent, heteroaryl donor ligand and their use as components of olefin polymerization catalysts, especially suited for preparing propylene copolymer products having high isotacticity and low molecular weight, are disclosed.
摘要:
Group 4 metal complexes comprising a polyvalent, heteroaryl donor ligand and their use as components of olefin polymerization catalysts, especially suited for preparing propylene/ethylene copolymer products having high isotacticity and low molecular weight, are disclosed.
摘要:
Hafnium complexes of heterocyclic organic ligands containing internal orthometallation and their use as components of olefin polymerization catalysts, especially for gas-phase olefin polymerizations, are disclosed.
摘要:
A 2,3-dihalopropanol is made by reacting 2,3-dihalopropanal with molecular hydrogen in the presence of a transition metal-containing catalyst, under conditions such that 2,3-dihalopropanol is formed. The reaction is particularly useful, for example, as Step (3) in a process to make epihalohydrin which may be generally prepared by:(1) reacting a 3-carbon hydrocarbon with an oxidizing agent to form acrolein;(2) reacting acrolein with a molecular halogen to form 2,3-dihalopropanal;(3) reducing 2,3-dihalopropanal with molecular hydrogen to form 2,3-dihalopropanol; and(4) cyclizing 2,3-dihalopropanol to make epihalohydrin.The process produces epihalohydrin using only about one mole of halogen per mole of epihalohydrin. It also uses substantially less water than existing processes.
摘要:
The present invention relates to a novel process for preparing alkali metal salts of diformylamide and a novel crystalline form of sodium diformylamide.