m is a number in the range from 1 to f, wherein f is the total number of {TAIL ~ isocyanate groups} per {HEAD ~ molecule} of isocyanate compound; and 
m is a number in the range from 1 to f , wherein f is the total number of { TAIL ~ isocyanate groups } per { HEAD ~ molecule } of isocyanate compound ; and
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH