Mr. NGUYEN, Nhat Thanh (3rd year doctoral student in Taniike Laboratory of Materials Chemistry Area) received Best Poster Presentation Award in A Chemistry Conference for Young Scientists 2020 (CHEMCYS2020).

■Date Awarded
February 21, 2020

■Title
Understanding the Thermal Degradation of Biobased Polyimide Derived from 4-Aminocinnamic Acid Photodimer

■Author
NGUYEN, Nhat Thanh

■Abstract
The development of high-performance biobased polymers plays a crucial role in the establishment of a sustainable low-carbon society. Recently, we have successfully synthesized new biobased polyamic acid (PAA) and polyimide (PI) from bioavailable aromatic diamine, which is a photodimer of 4-aminocinnamic acid (4ATA) derived from glucose via 4-aminophenylalanine using recombinant Escherichia coli. These polymers possess high thermal resistance and mechanical properties, being regarded as a promising engineering plastic. Herein, we investigate the thermal degradation mechanism of the biobased PI by various analytical techniques: thermogravimetric analysis (TGA), IR spectroscopy, solid-state 13C NMR, and tensile test. The TGA result for the biobased PI under dry air at 250 °C showed a mass loss behavior as typical for the auto-oxidation. The IR and 13C NMR results revealed that the cyclobutane ring of the diamine of 4ATA was the most susceptible to oxidative degradation. The thermal degradation of biobased PI started by oxidative degradation of the cyclobutane ring, followed by the formation of C=C double bonds and conjugated carbonyl species as the main oxidation products, which caused gradual deterioration of the strength, the ductility, and the transparency of the PI. We have successfully suppressed the thermal degradation by adding stabilizers to the PI formulation.

■Comment
I am greatly honored to win the award from a big conference tailored to young chemists worldwide. The conference offered me tremendous opportunities to advertise my research outcomes as well as to discuss with many young scientists from all over the world about typical research domains in chemistry. It was an unforgettable and precious memory. I am extremely grateful to Associate Professor Toshiaki Taniike and Professor Tatsuo Kaneko for their constant guidance during my research. Also, I would like to thank all members in Taniike laboratory for their cooperation. Finally, I would like to thank my family for always being by my sides.

April 2,2020