Synthesis and Characterization of Soluble Conjugated Poly(p-phenylenevinylene) Derivatives Constituted of Alternating Pyrazole and 1,3,4-Oxadiazole Moieties

En-Ming Chang; Shin-Lin Huang; Cheng-Tien Lee; Hui-Chang Lin; Chun-Yen Chen; Yu-Ying Huang; Shao-Kai Lin; Fung Fuh Wong

doi:10.1071/CH08344

RESEARCH ARTICLE

Synthesis and Characterization of Soluble Conjugated Poly(p-phenylenevinylene) Derivatives Constituted of Alternating Pyrazole and 1,3,4-Oxadiazole Moieties

En-Ming Chang ^B , Shin-Lin Huang ^C , Cheng-Tien Lee ^B , Hui-Chang Lin ^A , Chun-Yen Chen ^B , Yu-Ying Huang ^A , Shao-Kai Lin ^C and Fung Fuh Wong ^A ^D

+ Author Affiliations

- Author Affiliations

^A Graduate Institute of Pharmaceutical Chemistry, China Medical University, Taichung, Taiwan 40402, Republic of China.

^B Department of Chemistry, National Cheng Kung University, Tainan, Taiwan 70101, Republic of China.

^C Sustainable Environment Research Center, National Cheng Kung University, Tainan City, Taiwan 709, Republic of China.

^D Corresponding author. Email: wongfungfuh@yahoo.com.tw

Australian Journal of Chemistry 62(10) 1355-1362 https://doi.org/10.1071/CH08344
Submitted: 12 August 2008 Accepted: 10 February 2009 Published: 13 October 2009

Abstract

New soluble poly(p-phenylenevinylene) derivatives with 1,3,4-oxadiazole and pyrazole rings along the main chain were synthesized by Heck coupling. The new conjugated polymers are soluble in common organic solvents as a result of the fully conjugated backbone with dodecyloxy side groups. The polymers show relatively high glass-transition temperatures (up to 160°C) and good satisfactory thermal stability. Solutions of the polymers emit blue-greenish light with photoluminescence (PL) emission maxima around 490–500 nm. The PL spectrum of the polymer’s thin films, with a maximum at 515 nm, shows a red-shift (~20 nm), with respect to the solution spectrum. Cyclic voltammetry reveals that both conjugated polymers have reversible oxidation and irreversible reduction, making them n-type electroluminescent materials. The electron affinity of the new polymers was estimated as 2.73–2.74 eV. The weight-average molecular weights (M _w) of the new soluble polymers were in the range of 4790–4950.

Acknowledgements

We are grateful the National Science Council of Republic of China for financial support. We also appreciate Professor Mou-Yung Yeh for his illuminating discussion and helpful assistance in preparing this manuscript.

References

Synthesis and Characterization of Soluble Conjugated Poly(p-phenylenevinylene) Derivatives Constituted of Alternating Pyrazole and 1,3,4-Oxadiazole Moieties

Abstract

Acknowledgements

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