具官能基之可溶性低能隙聚噻吩衍生物之合成及性質探討

Abstract

在共軛高分子的領域中，由於聚噻吩衍生物擁有好的溶解度，加工性，環境穩定性，結構多樣化，以及其它有趣的性質，一直備受矚目。於聚噻吩衍生物的主鏈上引進柔軟的側鏈基團可以助其穩定性及改善其加工性質，以利進行更完整的分析。並且，導入側鏈基團亦可調整聚合物的電子性質，進而擴大其在工業界的應用可能性。 在此篇論文上，單體3,4-dihexyloxythiophene(簡稱DHOT)被合成出來，其側鏈己烷氧基團扮演兼具溶解度及推電子基之角色。以DHOT為主的聚噻吩衍生物亦被製備出來。以DHOT為主的均聚物，PDHOT，在許多有機溶劑中，如 CHCl3， toluene，DCB，呈現好的溶解性，並且具有低能隙之特性，能隙值在高分子溶液中約為1.44 e.V，在高分子薄膜中則約為1.42 e.V。 在文獻上鮮少有具官能基之低能隙共軛高分子之研究發表。在此，我們以DHOT與其它具有官能基之單體，如3-thienylacetonitril或3-thiopheneethanol，進行共聚合，期望製備出具有官能基之低能隙共軛高分子。研究發現，這些共聚物之能隙值約為2 e.V，並且對於有機溶劑具備溶解度。我們亦對這些共聚物進行基礎分析，如熱性質，光電性質之探討，在未來之應用上提供初步研究之成果。

Owing to the good solubility, processability, environmental stability, structural versatility, and other interesting properties, thiophene-based compounds have progressively emerged as a key system for the development of the conjugated polymers. The introduction of flexible pendants chains onto the backbone improves the stability and processability allowing a more complete characterization of the materials. Also such introduction modifies the electronic properties of the polymer enlarging the possibilities for industrial applications. In this study, the monomer, 3,4-dihexyloxythiophene(DHOT), with characters of soluble and electron-releasing hexyloxy side chains, was synthesized. The derivatives of polythiophene based on DHOT were prepared. The homopolymer based on DHOT, PDHOT, had good solubility in many organic solvents, such as CHCl3, toluene, DCB, and had low band gaps of ca. 1.44 e.V in polymer solution and of ca. 1.42 e.V in the thin film. There were less literatures on functionalised low band gap conjugated polymers. We copolymerized DHOT with functional monomers, 3-thienylacetonitril or 3-thiopheneethanol, in order to develop a low band gap conjugated polymers functionalised. These functionalised copolymers had band gaps of ca. 2 e.V, and they were soluble in common organic solvents. We also analysed the thermal properties, optoelectronic properties in this study to provide the preliminary study for potential applications.