wherein m and n are integers and R is {HEAD ~ a substituted or unsubstituted alkyl} or {TAIL ~ aryl group} 
wherein m and n are integers and R is { HEAD ~ a substituted or unsubstituted alkyl } or { TAIL ~ aryl group }
OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH TAIL TAIL TAIL TAIL TAIL TAIL