Compounds of formula B1 with amide group X are diamides obtained from macromolecular diamines by well known acylation reactions using e.g., {TAIL ~ the acid chlorides} or {HEAD ~ anhydrides} mentioned above 
Compounds of formula B1 with amide group X are diamides obtained from macromolecular diamines by well known acylation reactions using e.g. , { TAIL ~ the acid chlorides } or { HEAD ~ anhydrides } mentioned above
OTH OTH OTH 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 TAIL OTH HEAD HEAD HEAD HEAD HEAD OTH OTH