The urethane prepolymer is {TAIL ~ the reaction product} of a dihydroxy functional polyol and {HEAD ~ an isocyanate} 
The urethane prepolymer is { TAIL ~ the reaction product } of a dihydroxy functional polyol and { HEAD ~ an isocyanate }
OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD