摘要:
The monoether adduct of a tri(fluoroaryl)aluminum compound is prepared by an exchange reaction between a trihydrocarbylaluminum compound and a tri(fluororaryl)borane compound in a hydrocarbon solvent in the presence of a C.sub.1-6 aliphatic ether in an amount from 0.9 to 1.0 moles per mole of aluminum.
摘要:
Addition polymerization catalysts comprising a derivative of a Group 4 or Lanthanide metal compound prepared by oxidative activation, a process for preparation and an addition polymerization method utilizing such catalysts.
摘要:
The present invention provides unimolecular metal complexes having increased activity in the copolymerization of carbon dioxide and epoxides. Also provided are methods of using such metal complexes in the synthesis of polymers. According to one aspect, the present invention provides metal complexes comprising an activating species with co-catalytic activity tethered to a multidentate ligand that is coordinated to the active metal center of the complex.
摘要:
The present invention provides polycarbonate compositions having a tunable decomposition temperature. Suitable cationic additives (e.g., phosphonium, phosphazene, quaternary ammonium, guanidinium, pyridinium, arsonium, etc.) are disclosed for lowering the decomposition temperature of polymer compositions. The invention further provides methods of preparing such polymer compositions with tunable decomposition temperatures.
摘要:
A process for preparing tris(pentafluorophenyl)borane, the steps of the process comprising: a) forming a pentafluorophenyl metal compound wherein the metal is selected from Group 11 or 12; contacting the (pentafluorophenyl) metal compound from step a) with a boron halide compound to form tris (pentafluorophenyl)borane; and c) recovering the resulting tris(pentafluorophenyl)borane.
摘要:
A composition useful as an addition polymerization catalyst comprising: A) an inert support; B) a Group 3-10 or Lanthanide metal complex; and C) an activator compound capable of causing the metal complex B) to form an active polymerization catalyst, said compound corresponding to the formula: (A*+a)b(Z*J*j)−cd, (I) wherein: A* is a cation of charge +a, Z* is an anion group of from 1 to 50, preferably 1 to 30 atoms, not counting hydrogen atoms, further containing two or more Lewis base sites; J* independently each occurrence is a Lewis acid coordinated to at least one Lewis base-site of Z*, and optionally two or more such J* groups may be joined together in a moiety having multiple Lewis acidic functionality, j is a number from 2 to 12 and a, b, c, and d are integers from 1 to 3, with the proviso that a×b is equal to c×d.
摘要:
A thermal method for studying chemical responses, such as catalyzed polymerization reactions that includes the following three steps. The first step is to flow a chemical substance through a conduit, the conduit being in thermal communication with an electrical conductor, the electrical conductor being co-linear with the conduit, the electrical resistance of the electrical conductor being a function of the temperature of the electrical conductor. A length of stainless steel tubing can be used as both the conduit and the conductor. The second step is to flow electricity through the electrical conductor during the first step. The third step is to measure the electrical resistance of the electrical conductor during the second step to determine any change in the temperature of the conduit caused by a response of the chemical substance. An apparatus for studying chemical reactions that includes: a first conduit, the first conduit being an electrical conductor, the first conduit having a first end and a second end, the electrical resistance of the first conduit being a function of the temperature of the first conduit; a source of electricity, the source of electricity in electrical communication with the first conduit so that electricity can be flowed through the first conduit; a volt meter in electrical communication with the first conduit so that the voltage measured by the volt meter is an indication of the temperature of the first conduit.
摘要:
Catalyst compositions comprising a group 4 metal complex and an activator corresponding to the formula: (A*+a)b(Z*J*j)−cd, wherein: A* is a cation of charge +a, selected from the group consisting of ammonium-, sulfonium-, phosphonium-, oxonium-, carbonium-, silylium-, ferrocenium-, Ag+, and Pb+2; Z* is an anion group of from 1 to 50 atoms, not counting hydrogen atoms, further containing two or more Lewis base sites as defined in the claims; J* independently each occurrence is a Lewis acid coordinated to at least one Lewis base site of Z*, and optionally two or more such J* groups may be joined together in a moiety having multiple Lewis acidic functionality, j is a number from 2 to 12 and a, b, c, and d are integers from 1 to 3, with the proviso that a×b is equal to c×d.
摘要:
A compound useful as a catalyst activator corresponding to the formula: (A*+a)b(Z*J*j)−cd, wherein: A* is a cation of charge +a, Z* is an anion group of from 1 to 50 atoms not counting hydrogen atoms, further containing two or more Lewis base sites; J* independently each occurrence is a Lewis acid coordinated to at least one Lewis base site of Z*, and optionally two or more such J* groups may be joined together in a moiety having multiple Lewis acidic functionality, j is a number from 2 to 12 and a, b, c, and d are integers from 1 to 3, with the proviso that a×b is equal to c×d.