ISSN:
0887-6266
Keywords:
polypyrrole film
;
bending
;
water vapor sorption
;
diffusion
;
anisotropic expansion
;
Physics
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
Polypyrrole films containing perchlorate were electrochemically synthesized and the bending and recovery motion of the films obtained has been investigated. It was found that the thickness of the film and ambient relative humidity (RH) were crucial to the motion of film: An increase of the film thickness decreased the displacement of the bending but increased the bending stress. On the other hand, an increase of the ambient RH decreased both functions. The motion of film was caused by the difference of expansion on both sides of the film owing to anisotropic sorption of water vapor, which could be expressed by the diffusion-limited bending model. The diffusion coefficients calculated from the bending and recovery motion at 25°C, RH 50% were 12.2 × 10-8 cm2 s-1 and 3.5 × 10-8 cm2 s-1, respectively. The maximum expansion of the film surface calculated from the bending curve was about 0.36%. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. B Polym. Phys. 36: 2237-2246, 1998
Additional Material:
10 Ill.
Type of Medium:
Electronic Resource