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Microwave-Assisted Synthesis of Poly(L-lactic acid) via Direct Melt Polycondensation Using Solid Super-Acids

✍ Scribed by Hai Lei Cao; Peng Wang; Wei Bo Yuan

Publisher
John Wiley and Sons
Year
2009
Tongue
English
Weight
207 KB
Volume
210
Category
Article
ISSN
1022-1352

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✦ Synopsis

Abstract

A microwave‐assisted method of synthesizing high‐molecular‐weight PLA using SSA as green catalyst was developed. Yellowish PLA with $\overline M _{\rm v}$ above 2.0 × 10^4^ g · mol^−1^ was obtained when the reaction was run at 260 °C within 60 min under microwave irradiation with 0.4 wt.‐% SSA. This method used only 10% of the energy consumption necessary for conventional heating, and the catalyst could be used five times without losing catalytic activity. The improvement in $\overline M _{\rm v}$ and the decrease in the energy consumption under microwave irradiation suggested that selective heating and hot spots effects played a crucial role. The method was shown to be a time‐saving, green and a promising way to lower the cost and spread the application of PLA.

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