The effects of water on camphorsulfonic acid doped polyaniline and the use of this chiral conjugated polymer for the enantiorecognition of L-phenylalanine

Polyaniline is a conjugated polymer that can be doped from an insulating form to a conducting form with a strong acid. Polyaniline doped with one of the enantiomers of camphorsulfonic acid becomes chiral and can be characterized with circular dichroism. This chiral form of polyaniline is significant because it is the first example of an achiral polymer becoming chiral via a doping process.; When studying this chiral form of polyaniline, we observed a strange phenomenon when polyaniline is exposed to water prior to doping. The chirality as viewed with circular dichroism can be inverted depending upon the water content of the powder. This result is significant in that it takes us one step closer to fully characterizing this chiral polymer system and also helps clarify conflicting observations reported in past literature. Enclosed are the studies of this phenomenon along with experiments that attempt to explain this odd and unexpected behavior.; The mechanism for chiral induction in polyaniline via doping with camphorsulfonic acid has yet to be elucidated. Here, studies are presented to discern whether or not the doping molecules induce chirality upon the polyaniline backbone via a direct contact or nucleation mechanism. The former method entails each dopant exerting its own influence upon the chirality of the polymer while the latter supposes that only a few dopants dictate chirality. Our preliminary results indicate that the induction of chirality is due to nucleation.; Camphorsulfonic acid doped polyaniline is hoped to be used as a new material for the chiral separation of pharmaceuticals and other chiral molecules. There is a great need for the chiral separation of drugs because different enantiomers of the same drug can have very different effects upon the human body. Additionally, most of the materials presently used in chiral separations are costly and not very effective. Within this dissertation, evidence will be presented for the enantiorecognition of the amino acid L-phenylalanine over its enantiomer D-phenylalanine by this chiral system. These studies are the first of their kind and support the possibility of using chiral polyaniline for chiral separations.