论文标题:电活性苯胺齐聚物的分子设计及其性质的研究
Synthesis of Monodisperse Oligoanilines and Their Properties
论文作者 陈梁
论文导师 张万金,论文学位 博士,论文专业 高分子化学与物理
论文单位 吉林大学,点击次数 117,论文页数 165页File Size1241k
2005-05-01论文网 http://www.lw23.com/lunwen_83385752/ 金属同(异)核簇化合物;低温固相合成;三阶非线性光学性能
Homo-(hetero-)nuclear metal clusters Low; temperature solid-state syntheses Third-order; non-linear optical (NLO) properties
本论文主要是通过分子设计,合成了不同端基的单分散的苯胺齐聚物。利用一步氧化偶联的方法,合成了母体苯胺四聚体和五聚体。用端胺基保护的方法合成了胺端基的苯胺四聚体和五聚体。利用高氧化态母体苯胺齐聚物与还原态的苯基封端苯胺齐聚物反应合成苯基封端苯胺齐聚物的方法合成了苯基封端苯胺七聚体。在对这三种齐聚物的性质研究时发现:端基对齐聚物的性质影响很大,如齐聚物的激子峰的位置以及环境稳定性。通过向聚芳醚酮主链中引入苯胺齐聚物单元,合成了一种新型的具有电活性的聚芳醚酮,使其不仅具有聚苯胺的电化学性质,还具有聚芳醚酮的热稳定性。
Conjugated polymers (e.g., polyacetylenes, polythiophenes, polyanilines etc.)exhibit interesting properties for the development of lightweight batteries,electrochromic display devices, light-emitting diodes, optical switches, etc. However,these conjugated polymers like conventional polymers, have distribution ofmolecular weight, conjugated length and structure defects. The properties of theconjugated polymers are therefore the statistic averages of each structure. Thisrenders the difficulty of controlling properties of materials through tailoring of theirmolecular structure. By comparison, monodisperse conjugated oligomers,characterized by step-by-step increasing size of the π-system, can establish detailedstructure-properties relationship for their corresponding polymers. On the other hand,monodisperse conjugated oligomers could also act as excellent materials, becausestudies on the conjugated oligomers have revealed that the covergence limit ofoptical and electronic properties of many conjugated polymers [e. g.,poly(p-phenylenevinylene)s, ladder-type poly(p-phenylene)s, polythiophenes andpolyanilines] is already reached for oligomers containing only a few repeat units. In this thesis, we synthesized a series of monodisperse oligoanilnes and theproperties of these oligoanilines were studied. The thesis could be summarized asthe points shown below:1. One-step oxidative coupling reaction to synthesize parent anilinepentamer and hexamer Parent aniline pentamer and hexamer have been synthesized successfullythrough a novel method (oxidative coupling reaction), and were characterized by IR,MALDI-TOF-MS, elemental analysis and 1H-NMR. The chemical oxidation processof the pentamer and hexamer were studied by UV-Vis spectra. It was found thepentamer and hexamer were oxidized to EB form and then to the pernigranilineoxidation state.2. synthesis of amino-capped aniline tetramer and pentamer by themethod of amino terminal group protection Amino-capped aniline tetramer and pentamer were synthesized successfullythrough a novel method, this synthetic route protected the amino terminal group ofN-phenyl-1,4-phenylenediamine from further reaction. The tetramer and pentamerwere characterized by IR and MALDI-TOF-MS. The chemical oxidation process ofthe tetramer and pentamer were studied by UV-Vis spectra. It was found the(tetramer) pentamer was oxidized to its EB form and then to the pernigranilineoxidation state.3. Simple oxidative coupling reaction to synthesize phenyl-cappedaniline heptamer A convenient method has been reported for the synthesis of phenyl-cappedaniline heptamer. The method was accomplished by the reaction of parent anilinepentamer in the pernigraniline oxidation state withN,N-diphenyl-1,4-phenylenediamine in the leucoemeraldine oxidation state. Thephenyl-capped aniline heptamer in the leucoemeraldine oxidation state wascharacterized by IR, H-NMR, MALDI mass spectra and elemental analysis. Its 1chemical oxidation process was studied by UV-Vis spectra and the electrochemicalanalysis was studied by CV. It was found that the phenyl-capped aniline heptamershowed three oxidative waves in the cyclic voltammetry, different from polyaniline.We believed that the second peak was due to the occurring of nigraniline form.Phenyl-capped aniline heptamer in the EB state was synthesized and studied byUV/Vis spectra. We found the relative amount of amine and imine groups in theoligoanilines in the EB state bear the following relation with the ratio of the intensityof band a (π-π* transition) to the intensity of band b (exciton peak transition) mimine Intensityratio mimine + mamine Intensityratio stand for the ratio of the intensity of band b to that of band a. mamineis the amount of amine atom in the aniline oligomer in the EB state. mimine is theamount of imine atom in the aniline oligomer in the EB state. The intensityratio ofheptamer in the EB state equals to 0.27, so we considerd the heptamer in the EBstate only contain one quinoid ring4. The properties of oligoanilines The effect of chain length on position of excitonic peak
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