{TAIL ~ An example} of {HEAD ~ two additional and especially preferred gamma butyrolactone} derived monomer types according to the present invention are shown below: ##STR5## 
{ TAIL ~ An example } of { HEAD ~ two additional and especially preferred gamma butyrolactone } derived monomer types according to the present invention are shown below : # # STR5 # #
TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH