{HEAD ~ A process} 10 wherein said {TAIL ~ diisocyanate} is tolylene 2,4 diisocyanate or hexamethylene diisocyanate 
wherein
{ HEAD ~ A process } 10 wherein said { TAIL ~ diisocyanate } is tolylene 2,4 diisocyanate or hexamethylene diisocyanate
HEAD HEAD HEAD HEAD HEAD HEAD OTH REL OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH