Conductive polypyrrole and acrylate nanocomposite coatings: Mechanistic study on simultaneous photopolymerization

Facile preparation of conductive polypyrrole coatings with optimized binding and conductive properties for various electronic applications such as printing circuit boards and conductive inks using simultaneous photopolymerization method was investigated in this article. This method involves independent polymerization processes of pyrrole and acrylate monomers occurring simultaneously to produce conductive coating. While AgNO3 was used as oxidizing agent for photopolymerization of pyrrole, Irgacure 907 was used as the photoinitiator for the acrylate monomer, 1,6-hexanediol diacrylate. Based on Real-time Fourier Transform Infrared (RT-FTIR) spectroscopy characterization on polymerization rates and mechanisms, it was deduced that the selection of proper initial concentrations of monomers and their corresponding photoinitiators was essential to obtain optimized conductive and binding properties of the final coating. In addition, microscopic techniques such as TEM and SEM revealed that the size, morphology and dispersion of polypyrrole were also affected by the initial concentrations. Finally, conductivity measurements obtained via four-point probe method and conductive AFM were correlated with the spectroscopic and microscopic characterization to determine the optimal conditions for the preparation of conductive polypyrrole/acrylate coatings via this method. (C) 2016 Elsevier B.V. All rights reserved.