Conducting polypyrrole-coated macroporous melamine sponges: a simple toy or an advanced material?

Abstract

The present feature article offers a concise overview of recent research progress of the authors working in the design of macroporous conducting materials represented by polypyrrole-coated melamine sponges. The article highlights innovative results from the authors and suggests a perspective for future directions in the field of macroporous conducting polymer composites. The article also overviews this particular subject area and defines key challenges for this emerging field. The feasibility of diverse applications of polypyrrole/melamine sponges is demonstrated and includes deformation-sensitive materials, electromagnetic radiation shielding and electrically heated insulation materials. Cytotoxicity is addressed with respect to applications in biomedicine, and the adsorption of an organic dye serves as an example of the uses in environmental water-pollution treatment. A single-step deposition of polypyrrole during the oxidative polymerization of pyrrole provides the uniform coating of the sponge with an organic conducting phase. The conductivity of sponges was of the order of 10(-3) S cm(-1), increased with polypyrrole loading, and also by two orders of magnitude after the compression. Derived materials have also been prepared and tested. They are represented by polypyrrole-coated sponge converted by pyrolysis to a macroporous nitrogen-containing carbon, magnetic ferrosponge obtained by incorporation of magnetite, or the conventional globular polypyrrole coating replaced with polypyrrole nanotubes. Polypyrrole can also be simply decorated with silver nanoparticles. The macroporous conducting polypyrrole/melamine sponges and derived materials are considered to be of future scientific interest with broad application potential. [GRAPHICS] .