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