【作者】 王红；

【导师】 于世钧；

【作者基本信息】 辽宁师范大学 ， 有机化学， 2011， 硕士

【摘要】 第一部分设计合成了三种5-[4-(烷氧基)苯基偶氮]-1,3-苯二甲酰肼(6a,6b,6c),分别与三种不同二酰氯反应得到预聚物(pre-p1～pre-p5),经POCl3脱水关环得到五种含有偶氮苯和1,3,4-嗯二唑结构的聚合物(pl-p5)。第二部分设计合成了两种二-1,3,4-噻二唑胺类的新型化合物(1a,1b),分别与5-[4-(正十六烷氧基)苯基偶氮]-1,3-苯二甲酰氯反应得到两种新型含有偶氮苯和1,3,4-噻二唑结构的聚酰胺(p16-10,p16-6)。采用IR、UV-vis.和1HNMR对中间体及聚合物进行了结构表征。引入长烷氧基偶氮苯基团的聚合物(p1、p3、p4、p16-10)极易溶于氯仿、四氢呋喃等常用有机溶剂,p2、p5、p16-6易溶于N-甲基吡咯烷酮,弥补了主链含有1,3,4-嗯二唑和1,3,4-噻二唑结构聚合物溶解性差的缺点。凝胶渗透色谱(GPC)测得聚合物的分子量(Mw)分别为9774 g/mol(p1)、19801 g/mol(p3)、15612 g/mol(p4)、22814 g/mol(p5)、28804 g/mol(p16-10)、24832 g/mol(p16-6)；分子量分散系数(PDI)分别为1.625(p1)、1.611(p3)、1.709(p4)、1.723(p5)、1.708(p16-10)、1.738 (p16-6)；聚合物的特性粘度分别为0.0210 dL.g-1(p1)、0.0394 dL·g-1(p2)、0.0791 dL·g-1(p3)、0.0562 dL·g-1(p4)、0.0819 dL.g-1(p5)、0.1161 dL·g-1(p16-10)、0.0932 dL·g-1(p16-6)。p1～p5是主链共轭聚合物,刚性强,粘度较小,p16-10和p16-6是主链非共轭聚合物,粘度相对较大,且含嗯二唑聚合物(p1-p5)和含噻二唑聚合物(p16-10,p16-6)的粘度分别随着分子量的增大而增大。TG-DTA测得p1-p5、p16-10、p16-6的5%失重温度分别为332℃、335℃、345℃、347℃、359℃、320℃、322℃,表明聚合物具有很好的热稳定性。在365nm紫外光照射下,中间体和聚合物均发生明显的光致反-顺异构化,计算了中间体(6a、6b、6c)和聚合物(p1、p2、p3、p4、p5、p16-10、p16-6)的光致反-顺异构转化效率(R)、光稳态时顺式异构体含量(Y)及光致反-顺异构化速率常数(Kp),R分别为83.14％(6a)、83.54％(6b)、88.65％(6c)、59.32％(p1)、64.15％(p2)、76.79％(p3)、71.78％(p4)、71.26％(p5)、82.66％(p16-10)、73.68％(p16-6)；Y分别为87.34％(6a)、87.76％(6b)、93.04％(6c)、62.50％(p1)、67-35％(p2)、80.63％(p3)、75.37％(p4)、74.82％(p5)、86.80％(p16-10)、77.36％(p16-6)；kp分别为0.6130 min-1(6a)、0.7500 min-1(6b)、0.4610 min-1(6c)、0.6466 min-1(p1)、0.2078 min-1(p2)、0.3845 min-1(p3)、0.2501 min-1(p4)、0.2155 min-1(p5)、0.9003 min-1(p16-10)、0.9817 min-1(p16.6)。所有聚合物的R和Y均小于中间体,聚合物的形成产生新的空间位阻,偶氮苯反-顺异构化受到限制。噁二唑聚合物均为主链共轭聚合物,其R、Y、Kp均小于噻二唑聚合物。计算了聚合物的摩尔吸光系数(ε)和能隙(Eg),ε分别为2.8×10-4 L·mol-1·cm-1(p1)、3.4×10-4 L·mol-1·cm-1(p2)、5.1×104 L·mol-1·cm-1(p3)、7.9×10-4L·mol·cm-1(p4)、6.5×10-4L·mol-1·cm-1(p5)、3.6×10-4 L·mol-1·cm-1(p16-10)、3.0×10-4L·mol-1·cm-1(p16-6); Eg分别为2.081 eV(p1)、2.119 eV(p2)、2.275 eV (p3)、2.226 eV(p4)、2.153 eV(p5)、2.348 eV(p16-10)、2.322eV(p16-6)数据显示聚合物的Eg较小,在2-3eV之间,表明合成的聚合物具有电子传输能力。主链共轭聚合物pl～p5的共轭程度相近,其Eg小于p16-10和p16-6,说明噁二唑聚合物共轭性强于噻二唑聚合物,导电性能更好。聚合物浓度为1×10-6g·mL-1时,p1, p3, p4, p16-10, p16-6的THF溶液分别在375nm,360nm,410nm,375nm,395nm发射荧光宽峰；p2,p5的NMP溶液分别在472nm,442 nm发射荧光宽峰,这些聚合物均发射蓝紫色荧光。含长烷氧基偶氮苯及嗯二唑结构或噻二唑结构的聚合物具有良好的溶解性、热稳定性、光致反-顺异构化性能、荧光性能和电子传输性,在光电功能高分子材料领域具有潜在应用前景。更多还原

【Abstract】 In this paper, five polymers containing azobenzene and 1,3,4-oxadiazole unit (p1, p2, p3, p4, p5) were synthesized by a two step polycondensation reactions with 5-(4-alkoxy phenylazo) isophthaloyl dihydrazide (6a,6b,6c) and two dichlorides. Polyimides containing azobenzene and 1,3,4-thiadiazole were synthesized with 5-(4-hexadecyloxy phenylazo) isophthaloyl dichloride and novel bis-1,3,4-thiadiazole amine compounds (la,lb). The structures of monomers and polymers were confirmed by IR, UV-vis and 1H NMR. The introduction of long chain of alkoxy azobenzene significantly improves polymers’(pl, p3, p4, p16-10) solubility in common organic solvents such as chloroform and tetrahydrofuran etc. p2, p5, p16-6 can dissolve in NMP easily. The molecular weights and molecular weight distributions of the polymers were determined by gel permeation exclusion chromatography (GPC). The Mw are 9774 g/mol (p1),19801 g/mol (p3),15612 g/mol (p4),22814 g/mol (p5), 28804 g/mol (p16-10),24832 g/mol (p16-6); PDI are1.625 (p1),1.611 (p3),1.709 (p4),1.723 (p5),1.708 (pl6-10),1.738 (p16-6), respectively. The intrinsic viscosities are 0.0210 dL·g-1 (p1),0.0394 dL·g-1 (p2),0.0791 dL·g-1 (p3),0.0562 dL·g-1 (p4),0.0819 dL·g-1 (p5),0.1161 dL·g-1 (p16-10),0.0932 dL·g-1 (p16-6), respectively. The rigidity of the conjugated polymers (p1-p5) in the main chain is better, and the intrinsic viscosity are small, the intrinsic viscosity of the nonconjugated polymers (p16-10, p16-6) in the main chain are relatively great. In addition, the intrinsic viscosity of pl-p5 and p16-10, p16-6 are creasing with the molecular weights creasing, respectively. The thermal stability of polymers are characterized by TG-DTA, the 5% weight loss of the pl-p5, p16-10 and p16-6 are 332℃,335℃,345℃, 347℃,359℃,320℃,322℃, respectively. The trans-cis photoisomerization of monomers and polymers take place under the radiation of 365 nm UV light. The efficiency of trans-cis photoisomerization (R), the content of cis-isomer (Y) and the rate constant of photoisomerization (Kp) of monomer (6a,6b,6c) and polymers (p1, p2, p3, p4, p5, p16-10, p16-6) are calculated, R are 83.14%(6a),83.54%(6b),88.65%(6c),59.32%(pi),64.15% (p2),76.79%(p3),71.78%(p4),71.26%(p5),82.66%(p16-10),73.68%(p16-6), respectively; Y are 87.34%(6a),87.76%(6b),93.04%(6c),62.50%(p1),67.35%(p2), 80.63%(p3),75.37%(p4),74.82%(p5),86.80%(p16-10),77.36%(p16-6), respectively; kp are 0.6130 min-1 (6a),0.7500 min-1 (6b),0.4610 min-1 (6c),0.6466 min-1 (p1),0.2078 min-1 (p2),0.3845 min-1 (p3),0.2501 min-1 (p4),0.2155 min-1 (p5),0.9003 min-1 (p16-10),0.9817 min-1 (p16-6), respectively. The R and Y of polymers are smaller than that of the monomers, which is attributed to the increased steric hindrance in polymers and the trans-cis photoisomerization of azobenzene is limited. The molar absorption coefficient (ε) and energy gap (Eg) were calculated,εare 2.8x10-4L·mol-1·cm-1(p1), 3.4×10-4L·mol-1·cm-1(p2),5.1×10-4 L·mol-1·cm·1(p3),7.9×10-4L·mol-1·cm-1(p4),6.5×10-4L·mol-1·cm-1(P5),3.6×10-4L·mol-1·cm-1 (p16-10),3.0x10-4L·mol-1·cm-1 (p16-6), respectively; Eg are 2.081 eV (p1),2.119 eV (p2), 2.275 eV (p3),2.226 eV (p4),2.153 eV (p5),2.348 eV (pl6-10),2.322 eV (p16-6), respectively. The dates indicate Eg of polymers are small between 2-3 eV, which shows the polymers synthesized have the property of electron transmission. The conjugated degree of conjugated polymers (pl-p5) in the main chain is near, and the Eg of polymer (pl-p5) are greater than p16-10 and p16-6, which indicates that the conjugated capability of the polymers containing oxadiazole is better than the polymers containing thiadiazole. Therefore, the conductive property of polymers containing oxadiazole is better than that of polymers containing thiadiazole. The emission peak of polymers have one wide peak when the concentration is 1x10-6g·mL-1, the peak of THF solution of polymer (p1, p3, p4, p16-10, p16-6) is located at about 375nm,360nm,410nm,375nm,395nm, and the peak of NMP solution of polymer (p2, p5) is located at about 472 nm,442 nm, respectively. All the polymers emitted indigo blue fluorescence. The results indicated that azobenzene polymers with and oxadiazole or thiadiazole containing long chain of alkoxy unit show good solubility, good thermal, trans-cis photoisomerzation property and fluorescence property, which can be used in the filed of optical and electrical functional polymer materials.更多还原