Conducting Pseudopolyrotaxanes: A Chemoresistive Response via Molecular Recognition.

TitleConducting Pseudopolyrotaxanes: A Chemoresistive Response via Molecular Recognition.
Publication TypeJournal Article
Year of Publication1994
AuthorsMarsella, MJ, Carroll, PJ, Swager, TM
JournalJournal of the American Chemical Society
Keywordsconducting pseudopolyrotaxane

The synthesis and electrochem. properties of the macrocycle-contg. polythiophene I are described. I forms a self-assembled pseudopolyrotaxane in the presence of $π$-deficient guests such as paraquat and 1,1'-bis(4-fluorobenzyl)-2,2'-bipyridyl. Pseudopolyrotaxane formation results in both an anodic shift in the oxidn. potential of the polymer as well as a significant decrease in its max. cond. (ca. 52% at 45 mM guest). This effect is completely reversible. For comparative purposes, a nonmacrocyclic model polymer was also studied and showed no significant change in max. cond. under identical conditions. The results clearly demonstrate that the chemoresistive response is a direct result of host-guest complexation. Such a chemoresistor approach is an attractive route into conducting polymer-based sensors wherein resistivity is attenuated by perturbations arising from host-guest interactions. [on SciFinder(R)]