| abstract |
A process and a foam produced therefrom are disclosed in which multi-functional isocyanate, water, a catalytic amount of a urea polymerization catalyst, and a catalytic amount of an isocyanurate polymerization catalyst are reacted to form a rigid, closed cell, urea-modified polyisocyanurate foam suitable for use for retrofitting wall cavities with insulating material. The urea polymerization catalyst and the isocyanurate polymerization catalyst are present in the reaction mixture in relationship to the multi-functional isocyanate and water in amounts so as to produce a foam setting after substantially complete rising thereof. Activator compositions for preparing such foams are also disclosed. |