【作者】 王慧；

【导师】 武永刚；

【作者基本信息】 河北大学 ， 高分子化学与物理， 2022， 硕士

【摘要】 近年来,共轭梯形聚合物由于其独特的共轭平面结构,良好的热稳定性及光学性能,在有机发光二极管和有机场效应晶体管等领域得到了广泛的应用。杂原子的引入有利于调节共轭梯形聚合物的带隙和电荷传输性能,是聚合物改性的重要方式。本论文将氧、氮杂原子引入梯形材料中,合成了一系列的全氧桥共轭梯形齐聚物和氮、氧桥共轭梯形聚合物。希望制备性能更加优良的共轭梯形材料,并应用于有机半导体材料领域,论文的主要研究内容如下。1.第二章以4-溴-3-氟苯酚和1,4-二溴-2,5-二甲氧基苯等为起始原料,通过Miyaura硼化反应,Suzuki偶联反应,分子间亲核取代反应（S_NAr反应）制备得到了含有两个氧桥的小分子的模型化合物,并对其进行修饰最终得到了多种环增多的全氧桥共轭梯形齐聚物A2,A4,A6,A8,A10,A12。通过NMR,MS,PL,UV-Vis,TG,DSC和电化学工作站等对这六种齐聚物的结构,分子量,光学性能,热学性能和电化学性能进行了测试,并且还对其进行了能级和DFT的前沿分子轨道的计算。结果表明,其紫外吸收峰和荧光发射峰均随着齐聚物氧桥主链的增加而红移。A2,A4,A6,A8,A10,A12的荧光量子产率为0.85,0.87,0.82,0.80,0.78,0.75。TG测得这六种齐聚物失重5%时,均在300℃以上。循环伏安测得A2,A4,A6,A8的Band gap值为4.06 e V,3.86 e V,3.54 e V,3.55 e V。2.第三章以1,4-二溴-2-二甲氧基苯为起始原料,通过通过硝化反应,Ullmann偶联反应,还原反应等制备得到了2,7-二溴-3,6-二甲氧基-9H-咔唑。以此为单体,通过Suzuki偶联反应,分子间亲核取代反应（S_NAr反应）合成了含氮氧桥的共轭梯形齐聚物B2,B4,B6。对齐聚物B2,B4,B6的结构,分子量,光谱,热学稳定性和电化学性能进行了测试与表征。结果表明:随着氮氧桥环的增多,B4、B6与B2相比,它们的最大紫外吸收峰和最大荧光发射峰分别红移了34 nm,99 nm和67 nm,87 nm。通过TG测试,B2,B4,B6失重率为5%的热分解温度分别为210℃,400℃,450℃。循环伏安法测得B2,B4,B6的Band gap值为3.55 e V,2.88 e V,2.73 e V。第四章以含有烷基链的甲氧基咔唑类单体为原料,通过Suzuki偶联,S_NAr反应制备氮氧桥的共轭梯形聚合物,通过NMR、GPC、紫外-荧光-红外光谱、DSC、TG和电化学工作站对聚合物进行表征。结果表明,关环后的聚合物的红外谱图在3500 cm^-1处没有羟基伸缩振动峰的出现,氟谱中F原子的信号几乎看不到,聚合物的数均分子量为9766 g/mol,聚合物在450℃开始失重,其能带间隙为2.47 e V。通过一系列的表征可知,上述合成的全氧桥共轭梯形齐聚物,氮、氧桥共轭梯形聚合物均有着更大的共轭结构,良好的光学性能,优异的热稳定性能和优良的电化学性能,在光电材料领域存在一定的应用价值。更多还原

【Abstract】 In recent years,conjugated ladder polymers have been widely used in organic light-emitting diodes and organic field effect transistors because of their unique conjugated plane structure,good thermal stability and optical properties.The introduction of heteroatoms is helpful to adjust the band gap and charge transport properties of conjugated trapezoidal polymers,which is an important way for the polymer modification.In this thesis,oxygen and nitrogen heteroatoms are introduced into ladder materials,a series of full oxygen bridged conjugated ladder oligomers,nitrogen and oxygen bridge conjugated ladder polymers are synthesized.It is hoped that conjugated trapezoidal materials with better properties can be prepared and applied in the field of organic semiconductor materials.1.In this chapter,1,4-dibromo-2,5-dimethoxybenzene,4-bromo-3-fluorophenol are used as raw materials,through Miyaura boronation reaction,Suzuki coupling reaction,intermolecular nucleophilic substitution reaction（S_NAr reaction）,we prepared a small molecule model compound containing two oxygen bridges,and modified it to finally obtain a variety of ring-increased peroxy-conjugated ladder oligomers A2,A4,A6,A8,A10,A12.The structures,molecular weights,optical properties,thermal properties and electrochemical properties of these six oligomers were tested and characterized by NMR,MS,PL,UV-Vis,TG,DSC and electrochemical workstation,etc.Calculations of energy levels and preamble molecular orbitals of the DFT were performed.The results show that with the increase of the oxygen bridge backbone,the UV absorption peak and the fluorescence emission peak are more red-shifted.The fluorescence quantum yields of A2,A4,A6,A8,A10,A12 were 0.85,0.87,0.82,0.80,0.78,0.75.When the weight loss of these six kinds of oligomers was 5%measured by TG,they were all above 300℃.The band gap values of A2,A4,A6 and A8 were measured by cyclic voltammetry to be 4.06 e V,3.86 e V,3.54 e V and 3.55 e V.2.In this chapter,1,4-dibromo-2-dimethoxybenzene is used as the raw material,and2,7-dibromo-3,6-dimethoxybenzene-9H-carbazole is prepared through nitration reaction,Ullmann coupling reaction and reduction reaction.Using this as a monomer,the conjugated ladder oligomers B2,B4 and B6 containing nitrogen-oxygen bridges were synthesized through Suzuki coupling reaction and intermolecular nucleophilic substitution reaction（S_NAr reaction）.The structure,molecular weight,spectrum,thermal stability and electrochemical stability of oligomers B2,B4,B6 were tested and characterized respectively.The results showed that with the increase of nitroxide bridge rings,the maximum ultraviolet absorption peak and maximum fluorescence emission peak of B4 and B6 were red-shifted by 34nm,99nm and 67nm,87nm,respectively,compared with B2.Through the TG test,the thermal decomposition temperatures of B2,B4,and B6 with a weight loss rate of 5%are 210°C,400°C,and 450°C,respectively.The band gap values of B2,B4 and B6 measured by cyclic voltammetry were 3.55 e V,2.88 e V and 2.73 e V.The fourth chapter uses methoxycarbazole monomers containing alkyl chains as raw materials,through Suzuki coupling,S_NAr reaction to prepare nitroxide-bridged conjugated ladder polymers.The polymers were characterized by NMR,GPC,UV-Vis,PL,FIR,DSC,TG and electrochemical workstation.The results show that the infrared spectrum of the polymer after ring closure has no hydroxyl stretching vibration peak at 3500 cm^-1,the signal of F atom in the fluorine spectrum is almost invisiblethe,and number average molecular weight of the polymer is 9766 g/mol,the polymer begins to lose weight at 450℃,and its energy band gap is 2.47 e V.Through a series of characterizations,it can be seen that the above synthesized all-oxygen-bridged conjugated ladder oligomers and nitroxide-bridged conjugated ladder polymers have larger conjugated structures,good optical properties,excellent thermal stability and excellent performance.Electrochemical properties have certain application value in the field of optoelectronic materials.更多还原