Structural Control in Thin Layers of Poly(p-phenyleneethynylene)s: Photophysical Studies of Langmuir and Langmuir-Blodgett Films.

TitleStructural Control in Thin Layers of Poly(p-phenyleneethynylene)s: Photophysical Studies of Langmuir and Langmuir-Blodgett Films.
Publication TypeJournal Article
Year of Publication2002
AuthorsKim, J, Levitsky, IA, McQuade, TD, Swager, TM
JournalJournal of the American Chemical Society
Volume124
Pagination7710–7718
ISSN0002-7863
Keywordsfluorescent polymer Langmuir Blodgett film photophys spatial arrangement relationship, photophys spatial arrangement relationship Langmuir Blodgett film polyphenyleneethynylene
Abstract

We present the relationship between the spatial arrangement and the photophys. properties of fluorescent polymers in thin films with controlled structures. Eight surfactant poly(p-phenyleneethynylene)s were designed and studied. These detailed studies of the behavior of the polymers at the air-water interface, and of the photophys. properties of their transferred LB films, revealed key structure-property relationships. Some of the polymers displayed $π$-aggregates that are characteristic of an edge-on structure at the air-water interface. Monolayer LB films of these polymers showed greatly reduced quantum yields relative to soln. values. Other polymers exhibited a highly emissive face-on structure at the air-water interface, and did not form $π$-aggregates. The combination of pressure-area isotherms and the surface pressure dependent in situ UV-vis spectra of the polymers at the air-water interface revealed different behavioral details. In addn., the UV-vis spectra, fluorescence spectra, and quantum yields of the LB films provide design principles for making highly emissive films. [on SciFinder(R)]

DOI10.1021/ja0200600