Abstract
Poly(p-phenylenediamine) (PPDA) and also its ladder-like analogue were prepared by oxidation of p-phenylenediamine with ammonium peroxydisulfate in an aqueous solution of 0.4 mol L-1 hydrochloric acid and converted to PPDA bases. These were used as reductants of silver nitrate to silver nanoparticles in 1 mol L-1 methanesulfonic acid or in water at various mole ratios of silver nitrate to p-phenylenediamine units from 0 to 1.8.
The original conductivity of the PPDA, 10-12 S cm- 1, increased to the order of 100 S cm-1 for the PPDA-silver composites containing 27-40 wt% (i.e. 4.5-6.6 vol%) silver. Fourier transform infrared spectra indicated a practically unchanged molecular structure of PPDA in the composites.
In contrast, Raman spectroscopy showed the existence of regions with unchanged molecular structure of PPDA as well as the presence of regions containing silver particles and oxidized PPDA moieties.