Synthesis of chiral polyaniline and its memory effects

Using simple acid/base doping/dedoping chemistry, new chiral forms of polyaniline can be created upon the removal of the dopants. The mirror images of the circular dichroism spectra of R-camphorsulfonic acid and S-camphorsulfonic acid doped/dedoped polyaniline indicate that these two chiral forms of polyaniline is thermally stable to at least 80 °C and decreases gradually up to 180 °C. It can be regenerated by redoping with either chiral and achiral acids. Therefore, chiral dedoped polyaniline is remarkably stable and any reduction in chirality can be restored with any strong acid. These properties make dedoped polyaniline appear to be promising as a substrate for chiral recognition.