Preparation of chiral conducting polymer colloids

A novel method for the electrochemical synthesis of chiral conducting polyaniline (PAn) colloids has been developed, via the potentiostatic (+0.9V vs Ag /AgCl) polymerisation of aniline in the presence of either (1R)-(−)-10-camphorsulfonic acid ((−)- HCSA) or (1S)-(+)-10-camphorsulfonic acid ((+)-HCSA). The electrosynthesis was performed under hydrodynamic conditions in an electrochemical flow cell using polyethylene oxide as a stabiliser. The optical activity of the colloidal polyaniline dispersion was established by circular dichroism (CD) spectroscopy. Visible region CD bands were observed at ca. 420 run and were attributed to the macroasymmetry of the polyaniline salt chains. Mirror image CD spectra were obtained for colloids grown in the presence of (+)- or (−)-HCSA, suggesting enantioselectivity during colloidal salt formation.