abstract |
Novel polyurea prepolymer and quasi-prepolymers are contemplated, the compositions being the reaction products of various isocyanate components with various polyamine components. Isocyanate components contemplated include uretonimine-modified 4,4′ methylene diphenyl diisocyanate (MDI) 4,4′ MDI, 2,4′ MDI, aliphatic hexamethylene diisocyanate (HDI) trimer, HDI allophanate, and aliphatic HDI biuret. Polyamine components contemplated include primary amine-terminated poly(oxypropylene), secondary isopropylamine-terminated poly(oxypropylene), tetraethyl N,N′-(methylenebis(2-methyl-4,1-cyclohexanediyl)) bisaspartate, and poly[(3-aminopropyl)methylsiloxane-co-diphenylsiloxane]. |