【作者】 张宇轩；

【导师】 姜振华；

【作者基本信息】 吉林大学 ， 高分子化学与物理， 2014， 博士

【摘要】 偶氮聚合物因其在光存储、光开关、非线性光学材料、光调制和光机械等光子和光电信息领域表现出令人期待的应用潜力而备受关注。偶氮基团有很多独特的性能，如光致顺反异构和光致各向异性等，这些特性使偶氮聚合物具有了光诱导双折射和可形成光诱导表面起伏光栅等光响应性质。近年来，将偶氮基团引入到高玻璃化转变温度的聚合物体系成为一种提高偶氮聚合物光存储稳定性和热稳定性的有效策略。聚芳醚类聚合物是一类综合性能优异的特种工程塑料，因其具有耐热等级高、耐辐射、耐化学药品、耐疲劳、耐冲击、抗蠕变、耐磨、耐热水性好、阻燃性好、电性能优良等优异的综合性能，在热塑性聚合物领域占有极其重要的位置。聚芳醚材料在航空、航天、核能、信息、通讯、电子电信、生物医疗、石油化工、机械制造、交通运输等高技术领域得到了成功的应用和发展。功能性的聚芳醚材料已经在质子传导膜、非线性光学材料和光波导材料等领域得到初步研究。本论文从分子设计的角度出发，合成了一系列含有不同结构偶氮基团的单体，并通过亲核取代缩聚或接枝反应的方式，将偶氮基团引入到聚芳醚体系中，制备了一系列光响应偶氮聚芳醚材料。通过对所制备聚合物光致异构行为和光诱导双折射行为的研究，探讨了偶氮基团的结构和聚合物链段结构对偶氮聚芳醚材料光响应性能的影响。同时，我们也合成了一系列偶氮聚芳醚稀土配合物，并对其光响应性能和荧光性能进行了研究。具体研究内容如下：(1)通过磺酰氯和偶氮单酚的成酯反应合成了含单/双偶氮基团的双氟单体，基于所得双氟单体，经亲核取代缩聚反应制备了侧链含单/双偶氮聚芳醚共聚物。该系列偶氮聚芳醚光响应材料具有良好的热稳定性和较高的玻璃化转变温度。室温条件下，在532nm偏振激光照射下，所制备的侧链含单/双偶氮聚芳醚材料可产生稳定的光诱导双折射信号。其中，侧链含双偶氮聚芳醚产生的光稳态双折射值大于侧链含单偶氮聚芳醚产生的光稳态双折射值的2倍。同时，双偶氮聚芳醚材料的稳态保留值也大于单偶氮聚芳醚材料的稳态保留值。这是由于双偶氮基团比单偶氮基团共轭更长，位阻更大。双折射对温度的依赖性研究表明，侧链含双偶氮聚芳醚材料的光稳态双折射值随着测试温度的升高呈一个先上升后下降的趋势，这是偶氮基团光致取向和无规热运动共同作用的结果。在波长为355nm的干涉激光照射下，侧链含双偶氮聚芳醚薄膜可以形成规则的光诱导表面起伏光栅。(2)设计合成了一系列含有不同长度烷基溴的偶氮单体，并通过与含羟基聚醚砜进行亲核取代接枝反应制备了一系列含不同长度烷基侧链的偶氮聚芳醚材料。热力学性能测试结果表明，随着侧链烷基长度的增加和偶氮基团的引入，聚合物的玻璃化转变温度和热稳定性均相应下降。光致异构行为研究表明，随着烷基链长度的增加偶氮偶氮聚芳醚材料的光致异构化速率也相应增大。光诱导双折射测试表明，随着烷基链长度的增加,聚合物中偶氮基团的光取向速率也相应增加，光致取向稳定性稍有下降。得益于聚芳醚材料主链的刚性结构，所制备的含不同长度烷基侧链偶氮聚芳醚材料的稳态保留值均在82%以上。双折射信号多次写入和擦除实验结果表明，所制备的偶氮聚芳醚材料在信息存储方面有很好的抗疲劳性。(3)设计合成了含有烷基溴的偶氮羧酸单体，并通过与含羟基聚醚砜进行亲核取代接枝反应制备了侧链含偶氮羧酸聚芳醚材料。以所制备的侧链含偶氮羧酸聚芳醚为高分子配体，1,10’-邻菲罗啉为协同配体，稀土离子Eu3+为中心离子，合成了侧链含偶氮羧酸聚芳醚稀土配合物。光致异构行为研究表明，稀土的引入降低了偶氮聚芳醚材料光致异构化程度和速率。光诱导双折射测试表明，稀土的引入降低了偶氮聚芳醚材料光致取向速率和光致取向程度，但提高了偶氮聚芳醚材料的光致取向稳定性，即提高了双折射稳态保留值。(4)为了使偶氮基团的吸收峰与稀土离子的激发峰相分离，从在偶氮苯基团两侧增加推拉电子基团和增加偶氮基团共轭长度两种角度出发，设计并合成了两种新型偶氮双酚单体,并通过与含羧基的酚酞啉单体共聚制备了一系列侧链含羧基，主链含偶氮的聚芳醚材料。该系列主链含偶氮聚芳醚材料具有较高的玻璃化转变温度和良好的热稳定性。以该系列主链含偶氮聚芳醚材料为高分子配体，1,10’-邻菲罗啉为协同配体，稀土离子Eu3+为中心离子，成功制备了一系列主链含偶氮聚芳醚稀土配合物。紫外可见光谱测试表明，所制备的含萘基偶氮基团的聚芳醚稀土配合物中偶氮基团的吸收带与稀土配合物吸收带相分离。稳态荧光测试表明，相比于含苯基偶氮基团的聚芳醚稀土配合物，含萘基偶氮基团的聚芳醚稀土配合物的荧光强度有了很大提高。该系列主链含偶氮聚芳醚稀土配合物在干涉激光的照射下，可形成规则的光诱导表面起伏光栅。通过荧光显微镜可观察到规则的红色荧光光栅。更多还原

【Abstract】 In recent years, polymers containing azobenzene units (azo-polymers) have attractedconsiderable attention owing to their potential application in optical data storage, opticalswitching and nonlinear optical materials. Because of the unique reversiblephotoisomerization and photoinduced anisotropy of the azobenzene chromophores,azo-polymers can show a variety of photoresponsive variations, such as photoinduced phasetransition, photoinduced surface-relief-gratings (SRGs), and photoinduced birefringence.Recently, the introduction of azobenzene chromophores to some high-Tgaromatic polymers isattractive, because this strategy is helpful to improve the stability of azobene chromophoresfor optical storage application. Poly(aryl ether)s (PAEs) are a family of high-performanceengineering thermoplastics with excellent thermal, mechanical and electrical properties.Functionalized poly(aryl ether)s have been widely studied as proton exchange membranes(PEMs), light emitting materials and optical materials.In this work, we designed and synthesized a series of azobenzene monomers, which hadbeen introduced into poly(arylene ether)s by nucleophilic substitution polycondensationreaction or grafting reaction. Their trans-cis isomerization and optical properties wereinvestigated. We also synthesized a series of rare earth Eu3+complexes usingazobenzene-containing poly(arylene ether)s as macromolecular ligands, and theirphotoresponsive behavior and fluorescence properties were also investigated. The detailedresearches were summarized as the following: (1) A series of poly(arylene ether)s containing mono/bis-azobenzene moieties in the sidechain were successfully synthesized via a nucleophilic substitution polycondensationreaction. These polymers exhibit good thermal stability. Upon irradiation with a532nm Nd:YAG laser beam, the poly(arylene ether)s with bis-azobenzene pendantsshowed larger photoinduced birefringence intensity and better stability of thephotoinduced orientation than the poly(arylene ether)s with mono-azobenzenependants. The photoinduced birefringence of the PAEs with bis-azobenzene pendantsshowed a dependence on temperature: at the beginning, the birefringence valueincreased with temperature until reached its’ maximum, and then decreased. Byexposing their spin-coating films to an interference pattern of laser beam, tpoly(arylene ether)s with bis-azobenzene pendants could be used for fabrication ofsurface relief gratings (SRGs).(2) A series of azobenzene-containing side-chain poly(arylene ether)s with variousspacer lengths (2,6or12methylene units) were successfully synthesized via anucleophilic substitution grafting reaction between poly(ether sulfone)s withhydroxylphenyl side groups and azobenzene monomers AZOi. These azo-polymersshow good thermal stability with glass transition temperatures and5%weight-losstemperatures above119oC and347oC, respectively. The results ofphotoisomerization experiments indicated that the polymer with longer spacerscorrespond to higher photoisomerization rates. Upon irradiation with a532nmneodymium doped yttrium aluminum garnet (Nd:YAG) laser beam, they presentedremnant values of birefringence larger than82%of the saturation value ofbirefringence, indicating the good stability of the photoinduced orientation. Nofatigue phenomena have been observed after several cycles ofinscription–erasure–inscription sequences.(3) Poly(arylene ether)s containing azobenzene chromophores and carboxyl groups inthe side chain was synthesized via a nucleophilic substitution grafting reaction. Thecarboxyl-containing azo-PAE was used as macromolecular ligands. Using europium (Eu3+) as the central ion and1,10-phenanthroline (Phen) as co-ligand, a novel rareearth coordination polymer was prepared. The introduction of rare ions decreased thephotoisomerization rates. Upon irradiation with a532nm neodymium doped yttriumaluminum garnet (Nd:YAG) laser beam, the rare earth coordination polymer showedbetter stability of the photoinduced orientation and less value of photoinducedbirefringence than the carboxyl-containing azo-PAE.(4) A series of novel rare earth Eu3+coordination polymers were prepared by usingmain-chain azobenzene-containing poly(arylene ether)s as macromolecular ligand，and1,10-phenanthroline and DMF as co-ligands. The main-chainazobenzene-containing poly(arylene ether)s was synthesized via a nucleophilicsubstitution polycondensation reaction. The rare earth complexes were confirmed bymeans of IR and WAXD. The UV–vis spectra of the lanthanide complexes usingmain-chain phenylazo naphthalen poly(aryl ether)s as macromolecular showed thatthe absorption wavelength of the azobenzene chromophore was separated from theexcitation and emission wavelengths of the lanthanide ions. By exposing the films ofthe lanthanide complexes to an interference pattern laser beam, surface relief gratings(SRGs) could be formed on the films. Under the excitation, fluorescent patterns ofthe SRGs could be observed by the measurement of fluorescence microscopy.更多还原