PREPARATION AND PROPERTIES OF POLYANILINE CONTAINING PALLADIUM

Palladium complexes present in PdCl2 aqueous solutions of various acid ity have been introduced into polyaniline in the polyemeraldine base f orm (PANI). In these acidic media polyemeraldine undergoes protonation as evidenced by various spectroscopic methods, including FTIR, ESCA, and UV/vis. Additionally in the PdCl2 solutions of low acidity a parti al reduction of Pd2+ ions to Pd-0 takes place with concomitant oxidati on of polyemeraldine towards polypernigraniline. In the highly acidic PdCl2 solutions there are spectroscopic indications of the formation o f a coordination bond between palladium ions and nitrogen atoms of pol yaniline. PANI containing palladium exhibits catalytic activity in 2-e thylanthraquinone (eAQ) liquid phase hydrogenation which results in th e reduction of >C=O to greater than or equal to C-OH groups as well as in hydrogenation of aromatic rings in eAQ. (C) 1998 Elsevier Science Ltd.