Surface structure of conductive polypyrrole-containing composites

The surface structures of polypyrrole/silicon crosslinked poly( styrene/but yl acrylate/hydroxyethyl acrylate) (PSBH) conductive composite films were i nvestigated by X-ray photoelectron spectroscopy and scanning electron micro scopy. It was found that the conductive composite films were of a "sandwich " structure, and the surfaces greatly differ in chemical compositions and p hase morphologies from the bulk. The Si and N contents exhibit opposite gra dient change with the measured depth of the two surface layers in the compo site films, namely, the decrease in Si content and the increase in N conten t with increase in the depth of the surface layers. However, the Ndelta+/N ratios in polypyrrole decreased with the measured depth of the conductive c omposite film. It was also found that the conductive composite film based o n silicon crosslinked matrix exhibits more environmental stable than that b ased on linear matrix. (C) 1999 John Wiley & Sons, Inc.