【作者】 刘宽；

【导师】 杨慕杰；

【作者基本信息】 浙江大学 ， 高分子化学与物理， 2008， 博士

【摘要】 本论文设计与合成了6大类共10种功能共轭聚合物材料,包括6种新型的常规共轭聚合物与4种共轭聚电解质。它们分别为聚（苯撑乙烯撑-二苯基吡咯并吡咯二酮）交替共聚物系列（PDPPPV）、聚（苯撑乙炔撑-二苯基吡咯并吡咯二酮）交替共聚物（PDPPDOPE）、聚（苯撑乙炔撑-三苯基吡唑啉）交替共聚物（PTPPDDPE）、阳离子型聚苯撑乙烯撑共轭聚电解质（PPV-N（Et）₃⁺）、阴离子型聚苯撑乙烯撑共轭聚电解质（MPS-PPV）、间位聚苯撑乙炔撑型的共轭聚电解质（m-PPYPE-SO₃Na）和超支化型聚苯撑乙炔撑共轭聚电解质（HPPE-SO₃Na）。采用钯催化的Heck偶联缩聚反应制备了聚（苯撑乙烯撑-二苯基吡咯并吡咯二酮）交替共聚物系列（PDPPPV）。在Pd（PPh₃）₂Cl₂及相转移催化剂的存在下,采用Heck交叉偶联缩聚反应制备了聚（苯撑乙炔撑-二苯基吡咯并吡咯二酮）交替共聚物（PDPPDOPE）。对上述共聚物行了¹H NMR、IR、元素分析结构表征及热性能分析、紫外-可见吸收分析、荧光分析和电化学分析。这些聚合物的主链上由于存在电子给体与电子受体单元之间的电荷转移,所以比相应的聚苯撑乙烯撑或者聚苯撑乙炔撑均聚物扩大了在可见光区的吸收,有利于提高光伏器件的光富集效率。电化学分析表明,这两类含吡咯并吡咯二酮的共聚物均具有小的电化学能带隙(E_g^EC＜1.8eV),当其与MEH-PPV复合时可作为电子受体材料,显示出作为聚合物光伏电池活性层材料的可能性。它们作为电子受体与MEH-PPV构成的固体薄膜中,PDPPDOPV/MEH-PPV复合物表现出更好的荧光淬灭效果,而PDPPDOPE作为受体的薄膜其荧光淬灭程度稍差。两类聚合物不管在溶液中还是在薄膜状态下都显示了很大的Stokes位移,潜在成为荧光探针材料的前景。利用Gilch聚合反应得到了阴离子聚苯撑乙烯撑共轭聚电解质MPS-PPV与阳离子型聚苯撑乙烯撑共轭聚电解质PPV-N（Et）₃⁺,对这些共聚物进行了¹HNMR、IR结构表征及热性能分析、紫外-可见吸收分析与荧光分析,并且采用浸涂法在又指金电极表面上涂覆聚合物膜,制备电阻型湿敏元件,研究其湿敏特性。阴离子共轭聚电解质MPS-PPV的本征湿敏特性与非共轭阴离子聚电解质NaPSS相似,但在氧化性盐LiClO₄掺杂的情况下有所不同,这与氧化性掺杂剂LiClO₄掺杂对MPS-PPV聚合物共轭结构及导电性的影响有关。阳离子共轭聚电解质PPV-N（Et）₃⁺的本征湿敏特性表明该聚合物在25%～75%RH湿度范围内线性较好,灵敏度较高,其湿滞大小约为6%RH。利用Heck-Sonogashira偶联反应制备了含吡啶的间位聚苯撑乙炔撑共轭聚电解质m-PPYPE-SO₃Na。它具有荧光发射的溶剂依赖性以及浓度依赖性,在水溶液中存在聚集。该聚电解质在水溶液中与不同带电类型的表面活性剂之间存在一定的相互作用,阳离子型表面活性剂十六烷基三甲基溴化铵（CTAB）促进聚集而而非离子型高分子表面活性剂聚乙烯吡咯烷酮（PVP）促进解聚集。溶液的PH值对于该共轭聚电解质的光物理性质,特别是其荧光发射性质有巨大影响。缺电子小分子甲基紫精可以有效淬灭该共轭聚电解质在水溶液中的荧光发射,本征荧光发射的淬灭常数K_sv为5.65×10⁵M^-1,与普通的间位聚苯撑乙炔撑共轭聚电解质对甲基紫精的淬灭常数位于同一数量级,显示出较好的荧光敏感性能。利用Heck-Sonogashira偶联反应制备了一种新的含有1,3,5支化结构的超支化聚苯撑乙炔撑共轭聚电解质HPPE-SO₃Na。它具有荧光发射的溶剂依赖性和浓度依赖性,在水溶液中存在一定的聚集。该聚合物在水溶液中的最大吸收波长与本征荧光发射波长均介于小分子模型化合物PE-SO₃Na和直线型共轭聚电解质PPE-SO₃Na二者之间。该超支化共轭聚电解质与不同带电类型的表面活性剂之间存在相互作用,CTAB促进聚集而PVP促进解聚集。甲基紫精对该聚电解质的荧光发射有比较强的淬灭行为,本征荧光发射与聚集荧光发射的淬灭常数K_sv分别为2.03×10⁵M^-1和8.46×10⁵M^-1,分别为小分子模型化合物PE-SO₃Na淬灭常数的78倍和328倍,显示了荧光放大效应。生物体系中常见的金属离子对该聚电解质检测类似甲基紫精这类缺电子生物分子基本上不会造成明显的干扰,同样显示出好的荧光敏感特性。利用Heck-Sonogashira偶联反应合成了聚（苯撑乙炔撑-三苯基吡唑啉）交替共聚物PTPPDDPE,它具有好的热稳定性,溶解性和成膜性。该聚合物紫外-可见吸收和PL发射与单体三苯基吡唑啉相比有大幅度的红移。聚合物的电化学能带隙E_g^EC和光学能带隙E_g^OPT分别为2.37eV与2.45eV,属于中能带隙聚合物。该聚合物具有典型的分子内扭转电荷转移（TICT）结构,在溶液中的光物理性质受溶剂的极性性质影响很大,当溶剂极性增加时,荧光发射大幅度红移,具有成为对微环境敏感的TICT荧光探针材料的潜力。更多还原

【Abstract】 Six series of new functional conjugated polymeric materials were designed and synthesized,which named as alternating（phenylene vinylene）-（1,4-diketo-3,6-diphenyl pyrrolo[3,4-c]pyrrole）（DPP） copolymers（PDPPPV）,alternating （dioctyloxyphenylene ethynylene）-DPP copolymer（PDPPDOPE）,alternating （didecyloxyphenylene ethynylene）-triphenylpyrazoline（TPP） copolymer （PTPPDDPE）,cationic poly（p-phenylene vinylene） conjugated polyelectrolyte （PPV-N（Et）₃⁺）,anionic poly（p-phenylene vinylene） conjugated polyelectrolyte （MPS-PPV）,meta-linked anionic poly（p-phenylene ethynylene） conjugated polyelectrolyte（m-PPYPE-SO₃Na） and hyperbranched anionic poly（p-phenylene ethynylene） conjugated polyelectrolyte（HPPE-SO₃Na）,respectively.Alternating（phenylene vinylene）-DPP copolymers,were synthesized via Pd-catalyzed Heck cross-coupling polycondensation,and an alternating （dioctyloxyphenylene ethynylene）-DPP copolymer was prepared via cross-coupling polycondensation in the presence of Pd（PPh₃）₂Cl₂ and phase transfer catalysts.All these polymers were characterized by ¹H NMR,IR spectroscopy and elemental analysis.In addition,their UV-Vis and photoluminescence spectra,thermal and electrochemical properties were investigated.It was found that the copolymers exhibited much wider adsorptions in the range of visible light compared with corresponding homopolymers,which may result from the effective charge transfer between the electron donor and electron acceptor segments in the main chain of the copolymers and beneficial for the improvement in optical harvesting efficiency when applied in photovoltaic device.Electrochemical analysis revealed that the two kinds of DPP-containing polymers exhibited a low bandgap(E_g^EC＜1.8eV),and thus they could act as electron acceptor when blended with MEH-PPV and show potential applications as active layer materials in a polymer photovoltaic cell.The PL emission intensity of MEH-PPV is almost completely quenched when blended with the copolymers.Furthermore,the two kinds of copolymers exhibited large Stokes shifts both in solution and as a thin film,and could be promising candidates for fluorescence probe.An anionic poly（p-phenylene vinylene） conjugated polyelectrolyte MPS-PPV and a cationic poly（p-phenylene vinylene） conjugated polyelectrolyte PPV-N（Et）₃⁺ were prepared by Glich dehydrohalogenation polymerization and characterized by ¹H NMR, IR spectroscopy,UV-Vis spectroscopy,photoluminescence spectroscopy and thermogravimetric analysis.The two water-soluble conjugated polyelectrolytes were deposited on interdigitated gold electrodes by dip coating to construct resistive-type humidity sensors,and their humidity sensitive properties at room temperature were investigated over the range of 25-98%RH.It was found that the humidity sensitive properties of undoped anionic polymer MPS-PPV was similar to that of typical saturated polyelectrolytes such as sodium polystyrenesulfonate.In contrast,the LiClO₄-doped MPS-PPV showed different humidity sensing behavior compared with LiClO₄-doped NaPSS.The unusual humidity sensing behavior could be attributed to the influence of oxidative doping agent LiClO₄ on the conjugation structure and conductivity of the polymer MPS-PPV.The cationic polymer PPV-N（Et）₃⁺ exhibited high sensitivity,as characterized by impedance changing almost linearly on a semi-logarithmic scale from 10⁷ to 10⁴Ωwhen humidity decreased from 22 to 97%RH.In addition,moderate hysteresis（～6%RH） was observed.A meta-linked anionic poly（phenylene ethynylene） conjugated polyelectrolyte m-PPYPE-SO₃Na was synthesized via Pd-catalyzed Heck-Sonogashira coupling reaction.Its fluorescence spectra showed concentration- and solvent-dependency due to the aggregation of the conjugated polyelectrolyte in water solution.It was found that surfactants affected the aggregation of the polyelectrolyte.The interactions of cetyltrimethylammonium bromide（CTAB） and poly（vinyl pyrrolidone）（PVP） with m-PPYPE-SO₃Na in aqueous solution promoted the aggregation and broke the aggregation of the conjugated polyelectrolyte,respectively.The PH value of the solution had great influence on the photophysical properties of m-PPYPE-SO₃Na, especially the fluorescence properties.The fluorescence of the polymer in water solution could be effectively quenched by N,N’-dimethyl-4,4’-bipyridinium(Methyl viologen,MV²⁺).Linear fit of the quenching plots afford Stern-Volmer constants(K_sv) of 5.65×10⁵M^-1for intrinsic fluorescence emission of the polymer m-PPYPE-SO₃Na, which is of the same order of magnitude as the meta-linked anionic poly（p-phenylene ethynylene） conjugated polyelectrolyte m-PPE-SO₃Na and suggested its good fluorescence sensitivity.A hyperbranched anionic poly（phenylene ethynylene） conjugated polyelectrolyte HPPE-SO₃Na was synthesized via Pd-catalyzed Heck-Sonogashira coupling reaction. Its fluorescence spectra also showed concentration- and solvent-dependency due to the aggregation of the conjugated polyelectrolyte in water solution.The surfactants interacted with HPPE-SO₃Na in solution in different ways.The addition of CTAB and PVP resulted in the promotion and breaking of the aggregation of HPPE-SO₃Na in solution.The fluorescence of the polymer in water solution could be effectively quenched by N,N’-dimethyl-4,4’-bipyridinium(MV²⁺).Linear fits of the quenching plots afford Stern-Volmer constants(K_sv) of 2.03×10⁵M^-1 and 8.46×10⁵M^-1 for intrinsic and aggregated fluorescence emission,respectively.The fluorescence quenching efficiency of the intrinsic fluorescence emission and aggregation fluorescence emission by(MV²⁺) was about 78 and 328 times greater than that of model monomer PE-SO₃Na,respectively.Further more,metal ions commonly found in biology system could not interfere in the detection of MV²⁺ with HPPE-SO₃Na.Alternating（didecyloxyphenylene ethynylene）-TPP copolymer（PTPPDDPE） was synthesized via Pd-catalyzed Heck-Sonogashira coupling reaction.The UV-vis and PL spectra of the polymer exhibited a significant red shift compared with the monomer triphenylpyrazoline.The Electrochemical bandgap(E_g^EC) and optical bandgap(E_g^OPT) was estimated to 2.37eV and 2.45eV,respectively.It was found that the fluorescence of the polymer solution exhibited a larger red shift when the polarity of the solvent increased.This phenomenon could be attributed to the twist intramolecular charge transfer（TICT） in the main chain of polymer,which suggested its potential applications in a fluorescence probe for micro environment detection.更多还原