{HEAD ~ Such systems} typically also include a quasi prepolymer of an isocyanate and an active hydrogen containing material, and {TAIL ~ at least one amine resin}, and preferably an amine terminated chain extender 
typically include
{ HEAD ~ Such systems } typically also include a quasi prepolymer of an isocyanate and an active hydrogen containing material , and { TAIL ~ at least one amine resin } , and preferably an amine terminated chain extender
HEAD HEAD HEAD HEAD HEAD HEAD REL OTH REL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH