Synthesis, characterization, and biodegradation of maleic anhydride, ethylene glycol‐copolymerization modified poly( D,L ‐lactide acid) and their crosslinked products

Novel maleic anhydride (MAH), ethylene glycol oligomer‐modified poly( D,L ‐lactide acid) (PEMLA), and crosslinked‐PEMLA were synthesized via a series of chemical bulk modification. Briefly, MAH copolymerized with ethylene oligomer [EGO (including EG, PEG200, PEG400)] to give the PEMA; thereafter, D,L ‐lactide (DLLA) and prepolymers (PEMA) copolymerized to produce the PEMLA; at last, the crosslinked‐PEMLA was synthesized by free radical reaction of the PEMLA. The characterization of PEMLA and crosslinked‐PEMLA showed that the introduction of hydrophilic group O and CHCH increased the flexibility and hydrophilicity of PDLLA. Moreover, the degradation of PEMLA and crosslinked‐PEMLA were determined by molar weight changes and weight loss rate, and a special method, analysis of degradation positions via 1 H‐NMR, which indicated that the PEMLA and crosslinked‐PEMLA have nice degradation, and the change of content of MAH, EGO can regulate the degradation rate of PDLLA. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010