Synthesis of Polyimide Using Bio-based Diamine and Application to Network Polymer

Abstract

Biobased polyimides are synthesized from 4-aminocinnamic acid which was produced by a microorganism having genetically modified sugar metabolism. 4-Aminocinnamic acid can be photodimerized by ultraviolet, which is also a characteristic of cinnamate, and can be converted into biobased diamine. The obtained diamine can be employed into biobased polyimide syntheses by reacting with various tetracarboxylic dianhydrides, and exhibits the extreme high thermal resistivity among the existing bioplastics. In addition, the water-soluble polyimide was prepared by the treatment of biobased polyimide bearing ester side groups in an aqueous alkali metal solution. This water-soluble polyimide can also form a network structure by substitution with a polyvalent metal cation and impart water-insoluble properties. Furthermore, hydrogel is obtained by the condensation reaction of the side chain carbonyl group with water-soluble diamine.