Figure 6

Schematic structure of biodegradable hydrophilic polyurethane PEGU25.

n = 1, 2, 3,..., m = 1, 2, 3,..., Soft Segment (SS) is polyethylene glyco (PEG) or PCL (polycaprolactone). is isophorone diisocyanate (IPDI) or polyurethane (PU) chain segment.