A New Green Process for Synthesising High Quality PLLA Materials

Abstract:

Synthesis of Poly(L-lactide) (PLLA) by the ring-opening polymerization (ROP) of L-lactides in supercritical carbon dioxide (SC-CO₂) with co-solvent were studied. Effects of kinds of co-solvent on the molecular weight (MW) and the molecular weight distribution (MWD) of the resultant polymers were investigated by the gel permeation chromatography (GPC). The resultant polymers were also characterized with ¹H NMR, ¹³C NMR and FT-IR. It was found that PLLA with high purity and almost without racemization could be obtained by this technology and the acetone is the best co-solvent for this kind of polymerization. By using stannous octoate as initiator and acetone as co-solvent, PLLA having a weight-average molecular weight (M_w) near to 9×10⁴ and polydispersity index (PDI) of 1.7 was successfully synthesized.

• Periodical: Advanced Materials Research (Volumes 750-752)
• Pages: 1377-1380
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.750-752.1377
• Online since: August 2013
• Authors: Hui Li Shao, Xian Jue Zhou, Xue Chao Hu
• Keywords: Co-Solvent, High Purity, PLLA, SC-CO₂

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