【作者】 张志攀；

【导师】 石高全；

【作者基本信息】 清华大学 ， 化学， 2004， 硕士

【摘要】 聚噻吩衍生物是一类重要的导电聚合物,它们常常具有良好的电化学活性、环境稳定性以及可加工性能,被广泛地应用在电子学、光学、生物学等领域。本论文通过电化学方法或化学方法制备了三种新型聚噻吩衍生物,并对聚合物以及纳米复合材料进行了全面表征。1. 以三氟化硼乙醚溶液为电解液,进行了3-苯基噻吩电化学聚合,得到高质量聚(3-苯基噻吩)膜,进一步丰富了三氟化硼乙醚体系中导电聚合物的合成研究。与传统的中性体系如乙腈相比,三氟化硼乙醚介质的引入降低了3-苯基噻吩的氧化电位,提高了聚合物的性能。聚(3-苯基噻吩)膜具有良好的电化学活性、化学稳定性和环境稳定性,电导率为0.01 S/cm;而且力学性能好,其拉伸强度可达32～40 MPa。拉曼光谱检测结果表明,聚(3-苯基噻吩)膜在生长过程中聚合物掺杂程度随着沉积电量密度的增加而增大。2. 在三氟化硼乙醚和三氟化硼乙醚-三氟乙酸的混合电解质中,2-苯基噻吩可以通过电化学聚合生成聚(2-苯基噻吩)。三氟乙酸的加入降低了单体的聚合电位,加快了聚合速度。通过调节三氟乙酸的浓度,可以使聚合时电流效率增加到70%,在电极上形成致密的膜。聚(2-苯基噻吩)膜的红外光谱和拉曼光谱表明,聚合物中存在一定程度上的?-??偶联。去掺杂后的聚合物能够溶于一般的有机溶剂,在蓝绿光区有较强的荧光。3. 以1,10-二溴癸烷为起始原料,合成了一种新型功能化噻吩单体3-(10-巯基癸基)噻吩。在二氯甲烷-水的液液两相体系中,以该单体和氯金酸制备了3-(10-巯基癸基)噻吩单分子层包裹的金纳米颗粒。将金颗粒溶于二氯甲烷,加入三氯化铁聚合噻吩部分后,得到了金/聚(3-(10-巯基癸基)噻吩)核壳材料,并用高分辨透射电镜、红外光谱和拉曼光谱证明了核壳材料的生成。该反应采用四丁基溴化胺-二氯甲烷体系做为萃取剂,代替文献中使用的四辛基溴化胺-甲苯体系,降低了实验成本。同时,这种方法还可以进行铂、硒化镉等纳米粒子的包裹。更多还原

【Abstract】 The derivatives of polythiophene usually have desirable electrochemical activity, environmental stability and easy processibility, which provide potential applications in various fields as electronics, optics, biology, etc. In present dissertation, we have synthesized three new polythiophene derivatives via electrochemical or chemical methods and characterized the structures and properties of the obtained polymers.1. 3-phenylthiophene was electropolymerized in pure boron trifluoride diethyl etherate (BFEE) and free standing films of poly(3-phenylthiophene) (P3PhT) were yielded. This work has enriched the researches on electrosynthses of conducting polymers in the electrolyte of BFEE. The oxidation potential of the monomer was lower than that measured in a neutral medium of acetonitrile and thus the quality of the polymer was improved, which demonstrated good electroactivity, chemical and environmental stability. A typical film of P3PhT has a tensile strength as high as 32-40 MPa and a conductivity of 0.01 Siemens per centimeter. Raman spectral results demonstrated that the doping level of P3PhT films increased with the increase of deposited charge density during the electrochemical growth process.2. 2-Phenylthiophene has been electrochemically polymerized in BFEE and in a composite electrolyte of BFEE and trifluoacetic acid (TFA). The addition of certain amount of TFA into BFEE lowered the oxide potential of the monomer and accelerated the polymerization. A judicious choice of TFA concentration could increase the current efficiency of the electrosynthesis to 70%. The structure of the polymer has been examined by infrared and Raman spectroscopies, which showed evidence of ?,??-coupling in the polymer. The dedoped polymer can be dissolved in some common organic solvents and fluorescent spectral studies indicated the polymer is a blue-green light emitter. <WP=5>3. A new type of functionalized thiophene, 3-(10-mercaptodecyl)thiophene (MDT), was synthesized from 1,10-dibromodecane as the starting reagent. In dichloromethane-water liquid-liquid system, MDT reacted with tetrachloroaurate to yield monolayer protected gold nanoparticles (MPCs). Ferric chloride was added to a dichloromethane dispersion of MPCs to polymerize the thiophene moieties and the core-shell structure of gold nanoparticle/poly(3-(10-mercaptodecyl)thiophene) was yielded. High resolution transmission electron microscope, infrared and Raman spectroscopies were utilized to characterize the structure. In this reaction, tetrabutyl ammonium-dichloromethane system was used for extraction, which substituted traditional tetraoctyl ammonium-toluene system used in previous literatures and improved the reaction economically. Meanwhile, the facile and convenient approach developed here for the incorporation of gold nanoparticles can be also applied to other nanoparticles such as Pt, CdSe, etc.更多还原