Conducting composite cryogels based on poly(aniline-co-p-phenylenediamine) supported by poly(vinyl alcohol)

Abstract

Poly(aniline-co-p-phenylenediamine) cryogels stabilized by poly(vinyl alcohol) were prepared by one-step oxidative cryocopolymerization. Composite cryogels have macroporous structure with pore sizes up to tens of micrometers; however, copolymer cryogels have smaller pores compared to homopolymer cryogels. The cryogels containing 70 mol% and 80 mol% of aniline have the smallest pores and have the highest mechanical stability. The decrease in aniline fraction led to decrease of conductivity from 5×10–2 S cm–1 for polyaniline-based cryogel to <1×10–11 S cm–1 for poly(p-phenylenediamine) analogue. The cryogel with 80 mol% of aniline, which already had improved mechanical integrity, possesses only moderately decreased conductivity up to 5×10–4 S cm−1 compared with polyaniline-based cryogel. The corresponding changes in the molecular structure of the composite cryogels are reflected in their infrared and Raman spectra using 633 and 785 nm laser excitation.