Charge carrier transport in aromatic polyimides and polyimide/J-aggregate composites

摘要

In aromatic polymides based on 9,10-bis(aminophenyl) anthracene or 9,10-bis(phenylthio)anthracene, charge carrier transport has been studied by conventional time-of-light techniques. The electric field and temperature dependencies of both hole and electron drift mobility were observed. In amorphous film of the soluble polyimide, the drift mobility was found to reach the value of 10~-4 cm~2V~(-1)s~(-1). In film of the insoluble polyimide containing a crystalline phase, the mobility was lower by one or two orders of magnitude. The result is attributed to the presence of cavities in the crystalline film. The applicability of known theoretical models describing the temperature and electric field dependencies of mobility is discussed. It was found out that J-aggregates, formed in the soluble polyimides doped with cyanine dye molecules, play an active role in charge carrier transport in the electrolumunescence composites.