| Summary: | 碩士 === 國立交通大學 === 材料科學與工程研究所 === 84 === A series of electrochromic polymers were electropolymerized
from varioussubstituted anilines with one component or two
components. The substitutedanilines included o-anisidine, o-
aminobenzotrifluoride, anthranilonitrile,and 2-fluoroaniline. In
the cyclic voltammetry(CV) study, poly(o-anisidine)and o-
anisidine copolymer had the same electron transfer reaction :
(1)withthe formation of semiquinone radical cation (color from
pale yellow to green),(2)with the formation of sp2 hybrid in
nitrogen atoms by deportonation (colorfrom green to purple-
blue).However, the electrochemical parameters, △E1/2, were
different for these co-polymers. The values of △E1/2 were 425.5
mV, 442 mV, 465 mV for o-anisidine/ o-aminobenzotrifluoride, o-
anisidine / 2-fluoroaniline, and o-anisidine / anthranilonitrile
copolymers respectively at a molar ratio of 1/2. The UV-
VISspectra for the base form of these polyaniline copolymers
also confirmed the order of the feasibility of electrochemical
reaction as follows : o-aminobenzo-trifluoride > 2-fluoroaniline
> anthranilonitrile.The electrochromic device was composed of an
ITO glass as a counter electrode,a polymer electrolyte layer,
and a polyaniline copolymer deposited on the otherITO glass as a
working electrode. The polymer electrolyte, being made of poly(
acrylic acid)( PAA ), chlorine terminated poly(ethylene ether)(
PEC ), and PEC/LiClO4 polymer solution, was sandwiched between
the two electrodes to form an electrochromic device. It has been
observed that the cyclic life of the electro-chromic device
increased with the bulk of the substituted groups of the poly-
anilines. The cyclic life was of 4500 cycles for o-
aminobenzotrifluoride copolymer system longer than that of the
2-fluoroaniline system (around 4000cycles), and the cyclic life
of anthranilonitrile copolymer system was of 2000cycles. A
longer cyclic life of 5500 cycles for o-anisidine / o-
aminobenzotri-fluoride electrochromic system could also be
obtained by designing a specialcounter electrode.
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