Processing, Annealing and Sterilisation of Poly-L-Lactide.

N.A. Weir, Fraser Buchanan, John Orr, D.F. Farrar, A. Boyd

Research output: Contribution to journalArticlepeer-review

134 Citations (Scopus)


Poly--lactide (PLLA) is one of the most significant members of a group of polymers regarded as bioabsorbable. Degradation of PLLA proceeds through hydrolysis of the ester bonds in the polymer chains and is influenced significantly by the polymer's molecular weight and crystallinity. To evaluate the effects of processing and sterilisation on these properties, PLLA pellets were either compression moulded or extruded, subjected to annealing at 120°C for 4 h and sterilised by ethylene oxide (EtO) gas. Procedures were used to evaluate the mechanical properties, molecular weight and crystallinity. Upon processing, the crystallinity of the material fell from 61% for the PLLA pellets to 12% and 20% for the compressed and extruded components, respectively. After annealing, crystallinity increased to 43% for the compression-moulded material and 40% for the extruded material. Crystallinity further increased upon EtO sterilisation. A slight decrease in molecular weight was observed for the extruded material through processing, annealing and sterilisation. Young's modulus generally increased with increasing crystallinity, and extension at break and tensile strength decreased. The results from this investigation suggest that PLLA is sensitive to processing and sterilisation, altering properties critical to its degradation rate.
Original languageEnglish
Pages (from-to)3939-3949
Number of pages11
Issue number18
Publication statusPublished - Aug 2004

ASJC Scopus subject areas

  • Biotechnology
  • Bioengineering
  • Biomedical Engineering


Dive into the research topics of 'Processing, Annealing and Sterilisation of Poly-L-Lactide.'. Together they form a unique fingerprint.

Cite this