The carbodiimide can promote the formation of {HEAD ~ crosslinks} between {TAIL ~ carboxylate and amine groups} of the polyelectrolytes 
The carbodiimide can promote the formation of { HEAD ~ crosslinks } between { TAIL ~ carboxylate and amine groups } of the polyelectrolytes
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH