{HEAD ~ Plastics} which cure in a series of steps having urethane, urea, {TAIL ~ siloxane} and acrylate groups 
having
{ HEAD ~ Plastics } which cure in a series of steps having urethane , urea , { TAIL ~ siloxane } and acrylate groups
HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH REL OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH