Further investigations on the hydrolytic degradation of poly (DL-lactide)

Biomaterials. 1999 Jan;20(1):35-44. doi: 10.1016/s0142-9612(97)00226-3.


The hydrolytic degradation of poly(DL-lactide) (PLA50) material was investigated in order to elucidate the effects of temperature and acidity of the external medium on the degradation characteristics. It was observed that at 60 degrees C and at pH = 7.4, degradation was extremely rapid as compared with degradation at 37 degrees C. After only 2 days, heterogeneous degradation was observed due to larger internal autocatalysis. On the other hand, in the case of degradation at 37 degrees C in an acidic medium with pH = 3.7, the heterogeneous degradation was preceded by a much longer lag time. Water absorption was found to be pH dependent. At pH = 7.4, water absorption was increased due to the osmotic pressure driving the buffer solution into the polymer matrix to neutralize acidic endgroups, which was not the case for degradation at pH = 3.7. In both cases, the oligomeric stereocomplex was obtained as degradation residue at the end of the degradation period.

MeSH terms

  • Biocompatible Materials / chemistry*
  • Calorimetry, Differential Scanning
  • Hot Temperature
  • Hydrogen-Ion Concentration
  • Hydrolysis
  • Kinetics
  • Polyesters / chemistry*
  • Thermodynamics
  • Time Factors


  • Biocompatible Materials
  • Polyesters
  • poly(lactide)