Hydrolytic degradation behavior of poly(rac-lactide)-block-poly(propylene glycol)-block-poly(rac-lactide) dimethacrylate derived networks designed for biomedical applications.

For polymer-based degradable implants, mechanical performance and degradation behavior need to be precisely controlled. Based on a rational design, this work comprehensively describes the properties of photo-crosslinked polymer networks prepared from poly(rac-lactide)-block-poly(propylene glycol)-block-poly(rac-lactide) dimethacrylate precursors during degradation. By varying the length of poly(rac-lactide) blocks connected to a central 4 kDa polyether block, microphase separated networks with adjustable crosslinking density, hydrophilicity/hydrophobicity ratio, thermal, and mechanical properties are obtained. The materials are characterized by a low water uptake, controlled mass loss, and slowly decreasing wet-state E moduli in the kPa range.