ADVANCES IN BLOCKING AGENTS FOR ISOCYANATES AND BLOCKING AGENTS FOR AMINES USED IN CURING.

This paper describes theory and techniques which are available for controlling reactivity of isocyanate prepolymers with curing agents by totally or partially blocking one or both species. Using these techniques it is possible to prepare thermally cured polyurethane elastomers and coatings, and most recently polyurethane foams which are particularly suitable for applications where thin foam layers are desired. Extensive experimental results are tabulated and evaluated in terms of recommendations for practical uses.