The polymers have {TAIL ~ a controlled degree} of {HEAD ~ hydrophobicity} with a corresponding controlled degree of erosion in an aqueous or a biological environment of use 
The polymers have { TAIL ~ a controlled degree } of { HEAD ~ hydrophobicity } with a corresponding controlled degree of erosion in an aqueous or a biological environment of use
OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH