The alkyl alcohol is removed and the excess ethanolamine is reacted with {HEAD ~ ethylene} or propylene carbonate to form {TAIL ~ the urethane diol} 
to form
The alkyl alcohol is removed and the excess ethanolamine is reacted with { HEAD ~ ethylene } or propylene carbonate to form { TAIL ~ the urethane diol }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL