Use of non-thermal microwave effect for successful fast synthesis of plant-derived polylactic acid plastic -Plastic revolution with microwaves-

The Nagoya Institute of Technology(hereinafter "NITech", President; Hiroyuki Ukai, Address; Gokiso-cho, Showa-ku, Nagoya), the National Institute for Fusion Science (hereinafter "NIFS", Director General; Akio Komori, Address; 322-6 Oroshi-cho Toki) and Chubu Electric Power Co., Inc. (hereinafter "Chubu Electric", President & Director; Akihisa Mizuno, Address; 1 Higashi-shincho, Higashi-ku, Nagoya) have jointly developed a technology for swiftly manufacturing polylactic acid, using non-thermal effects of microwaves. Polylactic acid is nature-friendly plastic produced with the combination (polycondensation) of lactic acid, obtained by extracting and fermenting starch from sugarcane, corn or perishable waste. There is a high expectation of its broader proliferation as plastic not derived from petroleum. With this new technology, the plastics industry can produce plastic materials at a lower temperature and shorter time, potentially making a significant contribution to energy conservation. The outcome of the joint research is due to be published in "Polymer Chemistry" by the Royal Society of Chemistry (UK).

NITech, NIFS and Chubu Electric signed a joint research agreement three years ago. Their study has successfully used microwaves (handled by NIFS) for the polycondensation of lactic acid (handled by NITech) under a reflux condition (at constant temperature). In the process, they have also obtained academic insight on the non-thermal effect of microwave. The single-mode wave resonator was also used to separate microwave into electric component and magnetic component in order to examine their effects on polylactic acid synthesis, identifying that the electric component is more effective in promoting chemical reaction. Chubu Electric, which has extensive knowledge on technologies for efficient energy use, has led the effort to make practical application of the findings to the plastics industry's production process.

• Microwave

Microwave is a type of electromagnetic waves. Its most common use is in a microwave ovens for heating foods. More recently, it has been attracting attention as a new way of heat application in chemical reactions.

• Non-thermal effect

Non-thermal effects, with regard to microwave chemistry, refer to unusual phenomena that are observed during synthesis involving microwave heating but cannot be explained in terms of thermal energy. The concept is not clearly defined as yet since the history of microwave chemistry research is still very young. Many past reports on non-thermal effects have been linked to a thermal effect of thermal conduction speed, with expectations for further research.