Delayed action tin catalysts
OwnerRichard M. Gerkin, Oliver Schumacherinventors
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Abstract
An improvement in a process wherein an organotin compound is used as a catalyst is disclosed, wherein the improvement comprises: A) employing a latent catalyst that is substantially catalytically ineffective at room temperature, wherein said latent catalyst is selected from the group consisting of unsymmetrically substituted tetrahydrocarbyl tin compounds of the formula: RxR′4−xSn wherein R is a hydrocarbyl group that is substantially inert under usual conditions of storage and use, R′ is a hydrocarbyl group that is more reactive than R under conditions of use, x is 1, 2, or 3; and B) then heating the curable mixture to a temperature in the range of from about 30 up to about 99° C. to activate the catalyst.
Claims14
In a process wherein an organotin compound is used as a catalyst, the improvement comprising:
- A) employing a latent catalyst that is substantially catalytically ineffective at room temperature, wherein said latent catalyst is selected from the group consisting of unsymmetrically substituted tetrahydrocarbyl tin compounds of the formula:
- RxR′4−xSn
- wherein
- R is a hydrocarbyl group that is substantially inert under usual conditions of storage and use,
- R′ is a hydrocarbyl group that is more reactive than R under conditions of use,
- x is 1, 2, or 3;and
- B) then heating the curable mixture to a temperature in the range of from about 30 up to about 99° C. to activate the catalyst.
In a process for making a cured polymer by forming a mixture of an organic polyisocyanate and an active hydrogen-containing compound that is reactive therewith on curing to provide a polymer, and shaping and curing said mixture, the improvement comprising
- A) incorporating into said mixture a latent catalyst that is substantially ineffective to cure said mixture at room temperature, wherein said latent catalyst is selected from the group consisting of unsymmetrically substituted tetrahydrocarbyl tin compounds of the formula:
- R2R′2Sn,
- wherein R is a hydrocarbyl group that is substantially inert under usual conditions of storage and use, and R′ is a hydrocarbyl group that is more reactive than R under conditions of use;
- and
- B) then heating the curable mixture to a temperature in the range of from about 30 up to about 99° C. to activate said catalyst and cure said mixture.
In a process for making a cured polymer by forming a mixture of an organic polyisocyanate selected from the group consisting of MDI and TDI and a polyol that is reactive therewith on curing to provide a polyurethane, and shaping and curing said mixture, the improvement comprising:
- A) incorporating into said mixture a latent catalyst that is substantially ineffective to cure said mixture at room temperature, wherein said latent catalyst is selected from the group consisting of dibutyldiphenyltin and dibutyldibenzyltin;
- and
- B) then heating the curable mixture to a temperature in the range of from about 30 up to about 99° C. to activate said catalyst and cure said mixture.
Dependencies are inferred from the claim text.