The present invention provides an oil or gas wellbore polymeric cement comprising the reaction product of an aliphatic isocyanate, a trimerization catalyst, and a catalyst retarder, wherein the reaction occurs in the wellbore at a temperature of at least 250° F. (121° C.). Also provided is a method of reducing fluid loss from an oil or gas well, comprising producing a polyisocyanurate cement by combining an aliphatic isocyanate, a trimerization catalyst, and a catalyst retarder within a wellbore at a temperature of at least 250° F. (121° C.). The various embodiments of the invention meet the controllability and minimized toxicity needed for this application. Standard aliphatic polyisocyanates reduce handling concerns while providing the reactivity response that fits this temperature range.

Claims data not available