| abstract |
Novel polyurea prepolymer and quasi-prepolymer compositions are contemplated, the compositions being the reaction products of an isocyanate component and a secondary diamine component. Specifically, a an isocyanate component comprising uretonimine-modified 4,4′ methylene diphenyl diisocyanates are reacted with various polyamines to form prepolymers or quasi-prepolymers. The isocyanate component may additionally comprise one or more other isocyanates, including pure MDI, aliphatic HDI trimer, HDI allophanate, and aliphatic HDI biuret. |