Polyaniline derivatives：synthesis, characterization and applications in light-emitting diodes

• Main Authors: Sz-Sheng Chen, 陳思聖
• Other Authors: Ten-Chin Wen
• Format: Others
• Language: en_US
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/33858065664114011272

碩士 === 國立成功大學 === 化學工程學系碩博士班 === 91 === In this research, copolymers of 2,5-dimethoxy aniline (DMA) with 2,2-dithiodianiline (DTDA) were prepared for different molar feed ratios of DTDA by electrochemical polymerization in propylene carbonate (PC) containing 1 M LiClO4. Cyclic voltammetry, UV-visible spectroelectrochemical measurements and FTIR spectroscopy were used to identify the differences in optical properties and structures between the copolymer and the homopolymers (PDMA/PDTDA). The composition of the copolymer was determined by X-ray photoelectron spectroscopy (XPS) for the copolymers prepared with different feed ratios of comonomers. The fraction of DTDA units in the copolymers depends on the molar feed composition of DTDA in copolymerization. Scanning electron microscopy (SEM) reveals the morphological differences between the copolymer and PDMA. Many PANI derivatives have been extensively studied in our laboratory. It is an interesting topic to understand what effects will present in the PLED device using PANI derivatives as the hole-injection electrode. Although various reports on PANI from this aspect are available in literature, little attention has been paid to substituted derivatives of PANI. Poly(diphenylamine) (PDPA) is expected to possess the properties of poly(paraphenylene) and PANI. Hence, PDPA shows many special properties in electrochemistry, conductivity and electrochromism. In this work, the characterization of PDPA doped with camphor sulfonic acid (CSA) system will be studied through the examination of UV-Vis spectral, FTIR spectral, TGA and energy level. In addition, the polymer light emitting diodes fabricated with PDPA-CSA as a hole-injection layer. To investigate the effects of the PDPA-CSA on the performance of this PLED device, the characteristics of polymer light emitting diodes based on a single layer (MEH-PPV) and double layer (PDPA-CSA/MEH-PPV) are also compared.