Interfacial polymerization of polyanthranilic acid: Morphology controlled synthesis

Abstract

For the first time, the formation of hollow microspheres of the carboxyl functionalized self-doped conducting polymer polyanthranilic acid (PANA), based on a two phase oxidative polymerization technique using two immiscible solvents, is reported. The spherical morphology of the functionalized polymer is obtained using mild acid and chloroform as immiscible solvents. The polymer is further investigated using FT-IR, UV-vis, electrochemical, TGA and X-ray diffraction techniques and is compared with polyanthranilic acid formed using a one phase polymerization method. Unlike the amorphous, one phase synthesized polymer with a granular morphology, two phase polymerization provides a controlled hollow spherical morphology with higher thermal stability and crystallinity. The hollow nature of the sphere is further proven with TEM and controlled opening of the sphere by varying the pH above 7. A two phase polymerization is adopted for the morphology controlled synthesis of polyanthranilic acid (PANA). The resulting polymer is spherical in morphology with a diameter of 1-4 μm, and is highly crystalline and thermally stable, the opposite of the polymer synthesized by one phase polymerization. Controlled opening of the sphere is also observed by changing the pH. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.