BOOK OF ABSTRACTS
8
TH
I
NTERNATIONAL
C
ONFERENCE ON
A
DVANCED
P
OLYMERS
VIA
M
ACROMOLECULAR
E
NGINEERING
APME 2009
October 4
thto 7
th, 2009
Dresden, Germany
Poster 18
122
Blend or copolymer? Spectroelectrochemical evidence of
copolymerization or blending two monomer
Metin Ak, Mine Sulak Ak, Halil Çetişli, Ramazan Donat
Pamukkale University, Department of Chemistry, 20020 Denizli, Turkey
Conducting polymers have attracted great interest due to their ease of
synthetic accessibility and modified architecture which can control the
polymer properties (i.e., electronic, optical, conductivity, etc.)
[1]
. These
advanced systems can be modified to be amenable for use in the desired
application by changing the structure of starting monomers. Blending and
copolymerization are another frequently used methods in order to improve
the properties of the polymers [2].
A dipyrromethane functionalized monomer; 5-(4-tert-butylphenyl)
dipyrromethane (BPDP) was synthesized. Electrochemical polymerization,
copolymerization and blending of BPDP with 3,4-ethylenedioxythiophene
(EDOT) were achieved in LiClO
4
/AN. Spectral and electrochromic
properties of producs are investigated. Spectral properties of copolymer
and blend have great differences from each other and corresponding
homopolymers. Effects of differentiation feed ratio of monomers on
copolymers’ spectral properties are also investigated.
1- Terje A. Skotheim ,Handbook of Conducting Polymers, II. Ed. Marcel Dekker,
1998.
2- O. Turkaslan, M. Ak, C. Tanyeli, I. M. Akhmedov and L. Toppare, “J. Polym. Sci.,
Part:A Polym. Chem., 45(19), 2007, 4496-4503.
BLEND OR COPOLYMER? SPECTROELECTROCHEMICAL EVIDENCE OF
COPOLYMERIZATION OR BLENDING TWO MONOMER
Metin AK, Mine Sulak AK, Ramazan DONAT, Halil ÇETİŞLİ
Pamukkale University, Faculty of Sciences, Chemistry Department, 20017, DENIZLI, TURKEY
Introduction
Spectroelectrochemistry
Conducting polymers have attracted great interest due to their e
Conducting polymers have attracted great interest due to their ease of ase of
synthetic accessibility and modified architecture which can cont
synthetic accessibility and modified architecture which can control the rol the
polymer properties (i.e., electronic, optical, conductivity, etc
polymer properties (i.e., electronic, optical, conductivity, etc.) [1]. These .) [1]. These
advanced systems can be modified to be amenable for use in the d
advanced systems can be modified to be amenable for use in the desired esired
application by changing the structure of starting monomers. Blen
application by changing the structure of starting monomers. Blending and ding and
copolymerization are another frequently used methods in order t
copolymerization are another frequently used methods in order to improve o improve
the properties of the polymers [2]. the properties of the polymers [2].
H O + N H TFA HN NH BPDP
Figure 1:C13-NMR spectrum of BPDP Figure 2: 1H-NMR spectrum of BPDP
4 0 0 6 0 0 8 0 0 1 0 0 0 0 .2 0 .4 0 .6 0 .8 1 .0 4 0 0 6 0 0 8 0 0 1 0 0 0 0 .1 0 .2 0 .3 0 .4 4 0 0 6 0 0 8 0 0 1 0 0 0 0 .0 0 .1 0 .2 0 .3 0 .4 4 0 0 6 0 0 8 0 0 1 0 0 0 0 .4 0 .6 0 .8 1 .0 1 .2 1 .4 4 0 0 6 0 0 8 0 0 1 0 0 0 0 .4 0 .6 0 .8 1 .0 1 .2 4 0 0 6 0 0 8 0 0 1 0 0 0 1 .2 1 .6 2 .0 2 .4 2 .8 1 :0 . 2 a ) A b so rb an ce A b so rb an ce 3 7 3 n m A b so rb an ce 1 :0 . 4 b ) 3 8 5 n m 1 :0 . 5 c ) 4 0 0 n m 1 :0 . 8 d ) 4 7 5 n m 1 :1 e ) 4 8 4 n m 1 :1 . 2 f ) 5 0 3 n m 4 0 0 6 0 0 8 0 0 1 0 0 0 0 .1 0 .2 0 .3 0 .4 0 .5 1 :0 W a v e l e n g t h ( n m ) g ) 3 6 4 n m A b s o rb an ce W a v e l e n g t h ( n m ) 4 0 0 6 0 0 8 0 0 1 0 0 0 0 .1 0 .2 0 .3 0 .4 0 .5 0 .6 0 .7 0 :1 h ) 6 0 3 n m -0.6 -0.4 -0.2 0.0 0.2 0.4 0.6 0.8 1.0 -0.5 0.0 0.5 1.0 1.5 2.0 2.5 3.0 homo cv C u rr e n t d e n s it y (m A /c m ²) Potential (V)
Figure 3: Cyclic Voltammetry Graphs of P(BPDP), P(BPDP-co-EDOT) and PEDOT
300 400 500 600 700 800 900 1000 1100 0.12 0.16 0.20 0.24 0.28 0.32 0.36 0.40 0.44 A b sor b ance Wavelength (nm) -0.6 V -0.4 V -0.2 V 0.0 V 0.2 V 0.4 V 0.6 V 0.8 V a) 400 500 600 700 800 900 1000 0.7 0.8 0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.6 0.4 V 0.8 V 0.2 V 0.0 V -0.2 V -0.4 V -0.6 V A b sor b ance Wavelength (nm)
Figure 5 :Spectroelectrochemistry of P(BPDP) film a) (2D) b) (3D)
350 400 450 500 550 600 650 700 750 800 0,7 0,8 0,9 1,0 1,1 1,2 1,3 1,4 1,5 Ab sor b an ce Wavelength (nm) P(BPDP)-P(EDOT) blend P(BPDP-co-EDOT) copolymer
References
1.1. Ito, T.; Shirakowa, H. and Ikeda, S. J. ; PerichoJ.Polym. Sci., Ito, T.; Shirakowa, H. and Ikeda, S. J. ; PerichoJ.Polym. Sci., 1974, 12, 11.1974, 12, 11. 2.
2. Durandetti, M; Nedelecn, J. , J. Org. Chem, 1996, 61, 1748Durandetti, M; Nedelecn, J. , J. Org. Chem, 1996, 61, 1748--1755.1755.
3. Rao PD, Littler BJ, Geier GR, Lindsey JS. J Org Chem 2000;65:1084-1092. 4. Ak, M., Gancheva V.,Terlemezyan, L., Toppare L., EuroPolym J 2008;44 2567
Synthesis of 5-(4-tert-butylphenyl)dipyrromethane (BPDP) [3].
5-(4-tert-butylphenyl)dipyrromethane was synthesized according to
literature [3-4] (Scheme 1) (1.66 g, 33 %, mp 160-163 °C) BPDP was characterized with NMR spectroscopy (Fig 1-2).
Synthesis of BPDP -1,5-1,0 -0,5 0,0 0,5 1,0 1,5 -4 -2 0 2 4 6 8 C u rr en t d e n s ity (m A /c m ²) X Axis Title P(BPDP-co-EDOT) -1,5 -1,0-0,5 0,0 0,5 1,0 1,5 -3 -2 -1 0 1 2 3 4 5 Potential (V) Cu rr en t d e n s it y ( m A/c m ²) EDOT
The oxidation/reduction behaviors of monomer and polymer were investigated by cyclic voltammetry (CV) using 0.1 M LiClO4/AN supporting electrolyte/solvent couple. Experiments were carried out in an electrolysis cell equipped with ITO coated glass plate as the working, Pt wire counter and Ag wire pseudo reference electrodes. Figure 3 shows cyclic voltammetry graphs of P(BPDP), P(BPDP-co-EDOT) and PEDOT.
Cyclic Voltammetry
The best way of examining the changes in optical properties of conducting polymers upon voltage change is via spectroelectrochemistry (Fig 4). It also gives information about the electronic structure of the polymer such as band gap (Eg) and the intergap states that appear upon doping. The onset energy for the π-π* transition (electronic band gap) was 2.39 eV and λmax was found to be 364 nm from spectroelectrochemistry of P(BPDP) film (Fig 5).
Figure 7: a)Spectroelectrochemistry of compozite film b)UV Spectra of copolymer film Figure 6: Spectroelectrochemistry of P(BPDP-co-EDOT) film prepared different feed ratio of monomers Scheme1: Synthesis route of BPDP
Figue 4: Experimental setup of the spectroelectrochemical investigations
For investigation of difference between spectral properties of copolymer and compozite, P(EDOT)-P(BPDP) compozite was prepared. For this purpose firstly EDOT polymerized on ITO coated glass electrode and than BPDP polymerized on this electrode. Spectroelectrochemistry of compozite is shown in Fig.7a and UV spectrum of copolymer and compozite (Neutral states) is
shown in Fig.7b for comparison. Copolymer has only one λmax value but
compozite has two different λmaxvalues.
Conclusions
BPDP was synthesized and characterized.
P(BPDP), P(EDOT), P(BPDP-co-EDOT) and P(BPDP)-P(EDOT) polymer films synthesized and characterized succesfully..
Redox properties of these polymers were investigated by CV.
Polymer films synthesized on ITO electrode and spectroelectrochemical properties were investigated.π-π* transition wavelength of P(BPDP) fim was found to 354 nm and band gap was found to 2.39 eV.
Spectroelectrochemical properties of copolymers prepared by using different feed ratio of monomers were investigated.
It is found that, whereas copolymer has only one λmaxvalue, compozite has two
differentλmax.
Feed Ratio Investigation
The band gap energies and absorption maxima of the copolymers ar
The band gap energies and absorption maxima of the copolymers are different e different
than the values for PEDOT and P(BPMP) as expected. In addition,
than the values for PEDOT and P(BPMP) as expected. In addition, the the λλmaxmax
values of the copolymers are red shifted when compared with that
values of the copolymers are red shifted when compared with that of the of the
homopolymer, which is due to increase in conjugation length and
homopolymer, which is due to increase in conjugation length and the influence the influence
of high electron density resulting from the incorporation of EDO
of high electron density resulting from the incorporation of EDOT and Py units.T and Py units.
(Fig 6)
