Intricate relation between the content and interactive roles of β-cyclodextrin in fixing the characteristics of conducting polyaniline composites

This work is an investigation of the influence of beta-cyclodextrin (CD) on the synthesis and characteristics of conducting polyaniline composites (PCDs). In a systematic way, this influence was studied with two different approaches for five PCDs: (1) increasing the initial CD content under identical preparation conditions (three composites: PCD1, PCD2, and PCD3) and (2) using the same initial CD content (as in PCD2) under different preparation conditions (two composites: PCD4 and PCD5). The quite unexpected order of the electrical conductivity (PCD2 < PCD3 < PCD1 < PCD4 < PCD5), the IR and ultraviolet-visible spectroscopy features, and the scanning electron microscopy characteristics (the particle size decreased from PCD1 to PCD3 but increased for PCD4 and PCD5) all exposed and confirmed the markedly different physicochemical characteristics associated with the two groups of composites. PCD5 remained unique among the five (prepared in i-PrOH-H2O-acid; the other four were prepared in H2O-acid). Differences in the characteristics existed within the group also. The development of all these characteristics in an unrelated order was found to originate from the amount of CD in its two roles as encapsule and dopant toward polyaniline. The interrelation between the content and roles of CD was, however, intricate in combination with the experimental conditions employed. (c) 2005 Wiley Periodicals, Inc.