Method for preparing tin complex curing catalyst
AssigneeGeneral Electric Company
InventorJeffrey H. Wengrovius
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Abstract
Catalysts containing tin complexes such as dibutyltin bis(acetylacetonate), useful as curing catalysts for room temperature vulcanizable compositions, are prepared by the reaction of a dialkyltin oxide with a dione and a polyalkoxysilane at a temperature in the range of about 20.degree.-80.degree. C. At least 2 moles of dione and preferably at least 2 moles of polyalkoxysilane are employed per gram-atom of tin. The polyalkoxysilane removes water of reaction, driving the reaction to completion.
Claims12
A method for preparing a tin complex condensation catalyst which comprises effecting reaction, at a temperature in the range of about 20.degree.-120.degree. C., between the constitutents of a mixture comprising:
- (A) at least one dialkyltin oxide;
- (B) at least 2 moles, per gram-atom of tin in reagent A, of a diene of the formula ##STR6## wherein each of R.sup.1, R.sup.2 and R.sup.3 is independently hydrogen, R.sup.4, Si(R.sup.4).sub.3, acyl or nitrile and R.sup.4 is a hydrocarbon radical containing from 1 to about 18 carbon atoms, and
- (C) at least 1 mole, per gram-atom of tin in reagent A, of at least one polyalkoxysilane;
- whereby water formed in the reaction between reagents A and B is removed by reaction with reagent C.
Dependencies are inferred from the claim text.