Characterization of conducting polymers of ester linkage containing thiophene derivatives via mass spectroscopy


Tezin Türü: Yüksek Lisans

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Fen Edebiyat Fakültesi, Kimya Bölümü, Türkiye

Tezin Onay Tarihi: 2004

Öğrenci: EVREN ASLAN

Eş Danışman: LEVENT KAMİL TOPPARE, JALE HACALOĞLU

Özet:

In order to investigate the thermal and structural characteristics of terepthalic acid bis-(2-thiophen-3-yl-ethyl)ester (TATE), decanedioic acid bis-(2-thiophen-3-yl- ethyl) ester (DATE) and octanoic acid 2-thiophen-3-yl-ethyl ester (OTE), their corresponding homopolymers, copolymers with thiophene and polythiophene, pyrolysis mass spectrometry technique was utilized. The results were discussed in detail considering the effects of spacer group in between ester linkages. Thermal Gravimetry Analysis was used to investigate the weight loss for polymers and monomers. Conductivities of samples were measured by four-probe technique. It was found that when the ester linkages contain hydrocarbon chains, the growth of polymer occurred through both 2 and 5 positions. On the other hand, when the ester linkages contain more rigid groups such as phenyl, steric hindrance inhibited the growth of the polymer through 2- position and polymerization proceeded via coupling of thiophene moieties mainly at 5-position yielding a polymer with lower conductivity. Though the structure of P(OTE) is inherently different than P(DATE) and P(TATE) extent of network structure is also quite low for this polymer compared to PTh. Similar thermal characterizations were recorded indicating that thermal units were not significantly affected by the presence of TATE, DATE or OTE for all copolymer samples.