【作者】 王宝燕；

【导师】 苏致兴；

【作者基本信息】 兰州大学 ， 高分子化学与物理， 2009， 博士

【摘要】 自首次合成荧光聚合物被报道以来,荧光聚合物引起了人们的广泛关注,近年来,人们已经制备了不同类型的荧光聚合物。而在众多类型的荧光聚合物中,由于水溶性荧光聚合物克服了荧光小分子不易溶于水的缺点,具备了潜在的应用前景。在本文中,我们综述了荧光聚合物的研究进展,制备了含有香豆素,荧光素以及1,8-萘酰亚胺发色团的五种水溶性荧光聚合物并对它们的荧光性质做了详细的研究。本论文选用无毒、廉价以及与生物体有较好相容性的水溶性高分子作为原料,以功能化的香豆素、荧光素和1,8-萘酰亚胺作为发色团,通过活性基团修饰法和基于荧光功能单体制备荧光聚合物两种方式将有机荧光分子引入到聚合物基体中,实现了荧光小分子的高分子化。采用核磁（¹H NMR）,质谱（HR-MS）,红外光谱（FT-IR）,差示扫描量热法（DSC）,可见紫外分光光度仪（UV-Vis）和荧光光谱等方法对合成的荧光分子以及荧光聚合物的结构和性能做了表征,系统地研究了所合成的荧光聚合物的荧光性能。（1）我们首先采用活性基团修饰法,选择香豆素为发色团,使7-羟基-4-甲基香豆素与环氧氯丙烷反应,合成出带有活性环氧基团的7-环氧丙氧基-4-甲基香豆素（MEC）,然后通过开环反应将MEC接枝到聚乙烯醇的侧链上,制备了一种蓝紫色的荧光材料,实现香豆素的高分子化。研究体系在不同酸碱条件下聚合物荧光的变化,实验结果证明所合成的这种荧光材料与小分子7-羟基-4-甲基香豆素相比,环境的酸碱性对其荧光的影响不大。此外,还研究了温度（从0℃到60℃）对聚合物荧光强度的影响,得到荧光强度随温度变化的线性方程。随着温度的升高,聚合物荧光强度下降。实验证明所得的荧光聚合物具有良好的水溶性,其荧光强度对温度具有敏感特性。（2）我们采用基于荧光功能单体制备荧光聚合物的方法,选择荧光素为发色团,使它与丙烯酰氯反应,合成出含有双键的荧光素单体Ac-Flu,然后令其与丙烯酰胺共聚,制备得到含有荧光素生色团的水溶性荧光聚合物poly（Ac-Flu-co-AM）。研究了常见金属离子对聚合物荧光强度的影响,其中以Fe³⁺对聚合物的荧光淬灭程度最大。以Fe³⁺的浓度为横坐标,相对荧光强度I₀/I为纵坐标,得到了Fe³⁺的浓度与聚合物水溶液相对荧光强度存在线性关系。实验证明所得的荧光聚合物可以在水中作为一种潜在的检测Fe³⁺的荧光传感器来使用。（3）我们设计了带有哌嗪识别集团的香豆素荧光单体Ac-HMPC,采用基于荧光功能单体制备荧光聚合物的方法,使其与丙烯酰胺聚合,得到了一种水溶性的蓝色荧光聚合物poly（Ac-HMPC-co-AM）。再次用另一种制备荧光聚合物的方法实现了香豆素的高分子化。我们研究了水体系中pH和金属离子对聚合物的荧光强度的影响。随着pH的减小,荧光强度逐渐增强。在常见的金属离子中,Ni²⁺对聚合物的荧光增强程度最大。我们探讨了质子和金属离子对荧光增强的机理,为水溶性荧光聚合物在荧光传感领域的应用做了基础性研究。（4）我们利用第四章中制备的带有哌嗪活性功能基的香豆素,使它与烯丙基溴反应,制备得到了带有烯丙基可聚合双键的荧光单体。采用基于荧光功能单体制备荧光聚合物的方法,使其与乙烯吡咯烷酮进行自由基聚合得到了一种蓝色荧光聚合物poly（Al-HMPC-co-VP）。研究水体系中pH和金属离子对聚合物的荧光强度的影响,探讨其荧光增强的机理,并且与丙烯酰单体Ac-HMPC制得的荧光聚合物作对比,为荧光聚合物传感器的设计以及潜在应用展开了基础性的研究。（5）我们设计了含有1,8-萘酰亚胺为生色团荧光单体,使其与乙烯基吡咯烷酮共聚,制备得到含有1,8-萘酰亚胺生色团的水溶性荧光聚合物。研究水体系中pH和金属离子对聚合物的荧光强度的影响,pH对共聚物的水溶液的荧光峰有显著的影响,氢离子能增强单体和的荧光强度。金属离子Zn²⁺,CO²⁺,Cr³⁺,Ni²⁺和Cu²⁺对聚合物荧光强度均有增强作用,其中以Zn²⁺对聚合物的荧光增强程度最大。实验结果表明所制备的水溶性荧光聚合物具有潜在的检测Zn²⁺的特性。本论文成功地合成了五类新型的水溶性荧光聚合物,为荧光聚合物的制备提供了新的设计思路和合成方法,有望在此基础上进一步研究具有环境检测性能的荧光聚合物。更多还原

【Abstract】 Since the first fluorescent material composed of polymer as a substrate was reported, fluorescent polymers have attracted much attention and recently various new materials have been prepared. Water-soluble fluorescent polymers show much more potential application compared with organic molecules. In this dissertation, the development of new fluorescent polymers materials is reviewed. To overcome the defects of organic molecules that are insoluble in water, five types of water-soluble copolymers bearing coumarin, fluorescein and 1, 8-naphthalimide were designed and synthesized.In this paper, the modified coumarin, fluorescein and 1, 8-naphthalimide as chromophores were attached successfully on several avirulent, low-cost, biocompatible and water soluble polymers through two different methods, respectively. The synthesized monomer and fluorescent polymers were characterized by the methods of nuclear magnetic resonance （¹H NMR）, mass spectrography （MS）, fourier transform infrared spectroscopy （FT-IR）, ultra-violet-visible spectra （UV-Vis） and differential scanning calorimetry （DSC）, respectively. And the fluorescence behaviors of polymers were investigated in detail.（1） A novel water-soluble fluorescent material was prepared via ring-opening reaction between 4-methyl-7-（2, 3-expoxypropoxy） coumarin （MEC） and poly（vinyl alcohol） （PVA） （via its epoxy derivate）. The fluorescent behaviors of this material （PVA-MEC） in solution, solid and film were studied in detail. The results showed that the fluorescence of PVA-MEC arose from isolated dye molecules and had a good film forming ability. The effects of acid/base environments on PVA-MEC were also studied and the results showed that it was less affected by environment than 7-HMC. In addition, the temperature dependences of fluorescence of PVA-MEC were investigated in detail. The fluorescent polymer showed excellent linear response between fluorescence intensity and temperature. These observations suggest that PVA-MEC is an excellent fluorescent macromolecular material with a convenient method of preparation and had a good water-soluble ability. （2） An acrylic monomer bearing xanthene group, acryloyl-fluorescein （Ac-Flu） was synthesized from fluorescein and acryloyl chloride. The photophysical behaviors of Ac-Flu and its copolymer were explored by recording the fluorescence spectra in solution, solid state and film in detail. In addition, the ability of the copolymer to detect different metal cations in aqueous solution was investigated. The results showed that poly（Ac-Flu-co-AM） had a good linear response between the logarithm of concentration of Fe³ against the relative fluorescence intensity for Fe³⁺ concentration. The results suggest that this copolymer may offer potential as a reusable polymer sensor for Fe³⁺ ion in aqueous solution.（3） An acrylic monomer bearing couamrin moiety, 7-hydroxy-4-methyl-8-（4’-acryloylpiperazin-1’-yl） methylcoumarin （Ac-HMPC） was synthesized from 7-hydroxy-4-methyl-8-（4’-piperazin-1’-yl）methyl coumarin （HMPC） and acryloyl chloride （Ac）. The main photophysical properties of the fluorescent copolymer poly（Ac-HMPC-co-AM） were determined viewing its sensor for protons and metal cations. The fluorescent polymer displayed "on-off"switching in its fluorescence intensity over a wide pH scale. In addition, it was found the fluorescence enhancement of poly（Ac-HMPC-co-AM） in the presence of Ni²⁺ ion. The results suggest that copolymer may offer potential as a reusable polymer for sensor protons and Ni²⁺ ion in aqueous solution.（4） A monomer 7-hydroxy-4-methyl-8-（4’-allyloxypiperazin-1’-yl）methyl-coumarin with blue fluorescence was synthesized. Then it was copolymerized with N-vinylpyrrolidone to obtain a water-soluble fluorescent copolymer poly（Al-HMPC-co-VP）. The fluorescence characterstics of the polymer as a function of pH sensor were investigated in aqueous solution. It was found that the polymer displayed sensitive fluorescence signal amplification over a wide pH scale, which was ascribed to a photoinduced electron transfer from the peperazine receptor to the coumarin fluorophore. In addition, The influence of metal cations on the fluorescence intensity of poly（Al-HMPC-co-VP） were also studied. Obvious fluorescence enhancement was the photophysical response of the polymer to the presence of Ni ion. The results suggest that copolymer may offer potential as a reusable polymer for sensor protons and Ni²⁺ ion in aqueous solution.（5） A novel water-soluble colored polymer, based on 1, 8-naphthalimide, was synthesized through a series of easy reactions with high yields. It emitted green fluorescence both in an aqueous solution and in a solid state. Fluorescence characteristics of the polymer as a function of pH were investigated in aqueous solutions. The presence of metal cations (Zn²⁺, Co²⁺, Cr³⁺, Ni²⁺ and Cu²⁺) could enhance the fluorescence intensity of an aqueous solution of this polymer. It was sensitive to present in the studied system. The results suggest that this newly synthesized compound could work as a polymeric sensor responding to water polluted by Zn²⁺.In conclusion, the paper offered us a design of synthetic method that is simple, convenient and practical for the preparation of multifuctional fluorescent polymers, particularly fluorescent polymers sensors.更多还原