Abstract A novel catalyst combination for the trimerization of polyisocyanates to polyisocyanurates is disclosed. The catalyst combination comprises (i) a tertiary amine trimerization catalyst, (ii) an alkali metal salt of an N-substituted amide, and (iii) a dibutyl tin di(alkanoate) compound. The use of this catalyst combination in the preparation of polyisocyanurate spray foams enables the systems to be sprayed in either a 1:1 or 2:1 by volume ratio, or ratios between these limits interchangably with no alterations being required in reactant formulations. The polyisocyanurate foams produced using the novel catalyst combination of the invention are characterized by having high resistance to flame and heat distortion.
IN A CATALYST SYSTEM FOR TRIMERIZATION OF A POLYISOCYANATE WHICH CONSISTS ESSENTIALLY OF A TERTIARY AMINE TRIMERIZATION CATALYST, THE IMPROVEMENT WHEREIN SAID CATALYST CONTAINS I FROM ABOUT 20 TO ABOUT 80 MOLE PERCENT OF AN AMIDE SALT HAVING THE FORMULA
Claim 2
Dependent Claim
40 words
IN A CATALYST SYSTEM FOR TRIMERIZATION OF A POLYISOCYANATE WHICH CONSISTS ESSENTIALLY OF A TERTIARY AMINE TRIMERIZATION CATALYST, THE IMPROVEMENT WHEREIN SAID CATALYST CONTAINS I FROM ABOUT 20 TO ABOUT 80 MOLE PERCENT OF AN AMIDE SALT HAVING THE FORMULA
Claim 3
Dependent Claim
12 words
A cocatalyst according to claim 1 wherein the tertiary amine is N,N-dimethylcyclohexylamine.
Claim 4
Dependent Claim
13 words
A cocatalyst according to claim 1 wherein the amide salt is potassium N-phenyl-2-ethylhexamide.
Claim 5
Dependent Claim
32 words
A cocatalyst according to claim 1 wherein the amide salt is present in the form of a solution containing from about 25 percent to about 75 percent by weight in a diluent.
Claim 6
Dependent Claim
14 words
A cocatalyst according to claim 1 wherein the tin salt is dibutyl tin diacetate.
Claim 7
Dependent Claim
49 words
A cocatalyst system for the trimerization of a polyisocyanate consisting essentially of a. from about 10 to about 70 mole percent of N,N-dimethylcyclohexylamine; b. from about 20 to about 80 mole percent of potassium N-phenyl-2-ethylhexamide; and c. from about 3 to about 30 mole percent of dibutyl tin diacetate.
Claim 8
Dependent Claim
49 words
A cocatalyst system for the trimerization of a polyisocyanate consisting essentially of a. from about 10 to about 70 mole percent of N,N-dimethylcyclohexylamine; b. from about 20 to about 80 mole percent of potassium N-phenyl-2-ethylhexamide; and c. from about 3 to about 30 mole percent of dibutyl tin diacetate.
Claim 9
Dependent Claim
32 words
A cocatalyst according to claim 6 wherein the amide salt is present in the form of a solution containing from about 25 percent to about 75 percent by weight in a diluent.
Claim 10
Dependent Claim
18 words
A cocatalyst according to claim 7 wherein said diluent is a mixture of ethylene glycol and dimethyl formamide.