wherein {TAIL ~ R1} represents {HEAD ~ linear or branched alkyl groups} which have 1 to 7 carbon atoms, or aromatic groups having the following general formula 
wherein { TAIL ~ R1 } represents { HEAD ~ linear or branched alkyl groups } which have 1 to 7 carbon atoms , or aromatic groups having the following general formula
OTH TAIL TAIL TAIL TAIL TAIL OTH 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