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