Use of Lewis acids for the breakdown of gelatinous rare earth compounds in hydrocarbon solutions
AssigneeBridgestone Corporation
InventorThomas J. Lynch
Life of this patent
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Abstract
The present invention is directed to a process for the preparation of a gel-free hydrocarbon solution containing a lanthanide rare earth series compound by dissolving or synthesizing a lanthanide compound in an inert hydrocarbon solvent with a Lewis acid in an amount sufficient to prevent formation of highly viscous solutions. The present invention is also directed to the use of the gel-free Ln solutions formed by the recited process as co-catalysts for the polymerization of dienes. The Lewis acid is a group 2, 12, 13, 14 or 15 halide or organohalide, or a transition metal halide, excluding aluminum trialkyls.
Claims33
A gel-free solution consisting essentially of:
- a mixture of at least one lanthanide series compound having at least one rare earth element in the lanthanide series, an inert solvent, and a Lewis acid, the Lewis acid selected from the group consisting of a transition metal halide, an organometallic halide whose metal is of group 2, 12, 13 and 14 of the Periodic System, and a halide of an element of group 2, 12, 13, 14 and 15 of the Periodic System, the Lewis acid being present in an amount sufficient to prevent gel formation of the at least one lanthanide series compound when mixed with the inert solvent.
A process for preparing a gel-free catalyst solution consisting essentially of the steps of:
- dissolving at least one lanthanide series compound having at least one rare earth element in the lanthanide series in an inert solvent by the addition of a Lewis acid selected from the group consisting of a transition metal halide, an organometallic halide whose metal is of group 2, 12, 13 and 14 of the Periodic System, and a halide of an element of group 2, 12, 13, 14 and 15 of the Periodic System, the Lewis acid being present in an amount sufficient to prevent gel formation of the at least one lanthanide series compound when dissolved in the inert solvent;
- and optionally, adding an organic magnesium compound to the solution, the organic magnesium compound being of the formula MgR2R3 wherein R2 and R3 are the same or different and are hydrogen atoms or hydrocarbon substituents having 1 to 8 carbon atoms, excluding the case where R2 and R3 are both hydrogen atoms.
A process for preparing a catalyst solution containing at least one lanthanide series compound consisting essentially of:
- the direct synthesis of the at least one lanthanide series compound in an inert solvent followed by the addition of a Lewis acid in an amount sufficient to form a solution having a Brookfield viscosity of less than 1000 centipoise after treatment with the Lewis acid.
A gel-free catalyst solution consisting essentially of:
- (a) a mixture of at least one lanthanide series compound having at least one rare earth element in the lanthanide series;
- (b) an inert solvent;
- (c) a Lewis acid, the Lewis acid selected from the group consisting of a transition metal halide, an organometallic halide whose metal is of group 2, 12, 13 and 14 of the Periodic System, and a halide of an element of group 2, 12, 13, 14 and 15 of the Periodic System, the Lewis acid being present in an amount sufficient to prevent gel formation of the at least one lanthanide series compound when mixed with the inert solvent;
- and (d) an organic magnesium compound of the formula MgR2R3 wherein R2 and R3 are the same or different and are hydrogen atoms or hydrocarbon substituents having 1 to 8 carbon atoms, excluding the case where R2 and R3 are both hydrogen atoms.
Dependencies are inferred from the claim text.