{HEAD ~ A polymer} based on {TAIL ~ a dicarboxylic acid} and a diamine is prepared by polycondensation in an extruder, by 
based on
{ HEAD ~ A polymer } based on { TAIL ~ a dicarboxylic acid } and a diamine is prepared by polycondensation in an extruder , by
HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH