含卤素的共轭聚合物的合成与表征

发布时间：2018-04-10 18:33

本文选题：氯原子 + 溴原子　；参考：《华中科技大学》2014年博士论文

【摘要】：本论文探索出将氯原子引入到共轭聚合物主链的直接聚合方法,并将主链含有氯原子的共轭聚合物成功应用到聚合物发光二极管中；同时合成出侧链含有溴原子的共轭聚合物,探究了侧链溴原子对共轭聚合物光学性能、电化学性能的影响,并将其作为给体材料应用到有机/聚合物太阳能电池中。具体内容和主要结论概述如下：设计合成了2,3-双(3-正辛烷氧基苯基)-5,8-二溴-6,7-二氯喹喔啉,利用该分子中氯原子和溴原子在Stille反应中反应活性的差异,将其与2,5-双三甲基锡噻吩聚合,首次成功制备出主链含氯原子的、结构规整的给体-受体交替共聚物(PC1QT)。同时合成出其氟代(PFQT)、未取代(PQT)的结构相似的聚合物,以便系统研究氯原子对共轭聚合物性能的影响。尽管氯原子的电负性低于氟原子的电负性,但PC1QT比PFQT具有更深的LUMO能级。通过量子计算发现,与氟原子不同的是,氯原子扭曲了聚合物主链,使LUMO能级局域在受体单元中。这可能是PC1QT具有更低的LUMO能级的原因。而使用联噻吩双锡盐作为给体单元合成的含氯聚合物PC1Q2T,与PC1QT相比,具有相似的LUMO能级和较高的HOMO能级。说明含氯共轭聚合物的HOMO和LUMO能级可以独立调控。同时因为氯原子的位阻效应,这些含氯共轭聚合物的吸收光谱明显的蓝移,Stokes位移增大,自吸收减小。以2,3-双(3-正辛烷氧基苯基)-5,8-二溴-6,7-二氯喹喔啉为受体单元,调节给体单元中噻吩个数,合成出三种红光聚合物材料PC1Q2HT、PC1Q3T和PC1Q4T。将PC1Q2HT、 PC1Q3T和PC1Q4T作为客体材料,选用高效绿光材料F8BT为主体材料,制备聚合物发光二极管器件。以PC1Q3T为客体材料制备出了发光峰位于678nm,色坐标为(0.66,0.34),亮度接近2000cd m-2,外量子效率超过1%的深红光聚合物发光二极管。以PC1Q4T为客体材料制备出了发光峰位于692nm,色坐标为(0.67,0.32),亮度接近1500cd m-2的深红光聚合物发光二极管；发光峰位于708nm,色坐标为(0.69,0.31),亮度超过400cd m-2,外量子效率超过0.6%的近红外聚合物发光二极管。设计合成出4,7-二溴-5,6-二氯苯并[1,2,5]噻二唑,并以其为受体单元合成出共轭聚合物。由于该分子内氯原子和溴原子的反应活性在Stille反应中差异较小,无法作为单体直接用于聚合；但可以通过Suzuki聚合得到主链含氯原子的共轭聚合物。将氯原子引入到苯并噻二唑单元上,会使聚合物材料的LUMO能级升高。分析量子计算结果,推断造成氯原子在喹喔啉体系和苯并噻二唑体系中对能级调控作用差异的原因可能是喹喔啉和苯并噻二唑中吡嗪环和噻二唑环的电子能力和位阻存在差异。以4,7-二(5-溴-2-噻吩基)-5,6-二氯苯并[1,2,5]噻二唑为受体单元,以2,7-双频哪醇硼酸酯-芴为给体单元合成的聚合物PFC1DTBT作为客体材料以3%的浓度掺杂到主体绿光材料F8BT中,制备出器件结构为ITO/PEDOT:PSS(30nm)/F8BT:聚合物(100nm)/Ca (20nm)/Al(100nm)的聚合发光二极管器件,电致发光峰位于632nm处,色坐标为(0.60,0.40),亮度最大可以达到15580cd m-2,电流效率为1.2cd A-1,最大外量子效率为1.1%。将溴原子引入到给体材料的侧链,通过调节含溴单元的比例,合成出一系列给体材料。发现在溶液中,聚合物的摩尔吸光系数随着含溴比例的变化有先减小后增大的趋势,荧光光谱峰值随溴含量的增加而逐渐红移；薄膜状态时,随着含溴比例的增加,吸收光谱中的肩峰越发明显,但聚合物的荧光光谱基本相同。这是因为溴原子被极化后与材料间的偶极-偶极相互作用弱于聚合物链段间的偶极-偶极相互作用。溶液中聚合物链段间相互作用较弱,枝接在侧链的溴原子被极化后对材料的影响得以显现；但薄膜状态时,聚合物链段间相互作用占主导地位。同时溴原子引入的分子间弱相互作用,促进了材料的堆积,使吸收光谱中肩峰的强度随溴含量的提高而增强。
[Abstract]:This paper will explore the chlorine atom by direct polymerization of conjugated polymer backbone, and conjugated polymers containing chlorine atom backbone successfully applied to polymer light emitting diode; at the same time the synthesis of conjugated polymers with side chain containing bromine atom, explores the side chain of bromine atoms on the optical properties of conjugated polymers, affect the electrochemical performance, and as to the material applied to organic / polymer solar cells. The specific contents and main conclusions are as follows:
The design and synthesis of 2,3- (3- is octyloxy phenyl) -5,8- -6,7- two dibromo dichloro quinoxaline, using chlorine atom or bromine atoms in the molecular differences in reactivity in the Stille reaction, the 2,5- dual three methyl tin thiophene polymerization, have been prepared for the first time the backbone of the chlorine atoms, regular structure to acceptor alternating copolymer (PC1QT). At the same time the synthesis of fluorinated (PFQT), unsubstituted (PQT) polymers with similar structure, in order to study the chlorine atom of conjugated polymer system performance. Although the chlorine atom electronegativity below the electronegativity of fluorine, but PC1QT is deeper than LUMO level PFQT. Through quantum computing, unlike fluorine atom, chlorine atom has distorted the polymer backbone, the LUMO level in the local receptor unit. This may be the reason why LUMO PC1QT has a lower level. And the use of bithiophene double tin salt as donor cell synthesis The chlorine containing polymer PC1Q2T, compared with PC1QT, HOMO has the similar LUMO level and higher level. The results showed that HOMO and LUMO levels of chlorine containing conjugated polymers can independently control. At the same time because of the steric effect of chlorine atoms, the chlorine absorption spectra of conjugated polymer obviously blue shift and Stokes displacement increases, self absorption decreases.
2,3- (double 3- octane oxygen phenyl) -5,8- dibromo dichloro quinoxaline -6,7- two receptor unit, adjusted to the unit in a number of thiophene, synthesis of three kinds of red polymer PC1Q2HT, PC1Q3T and PC1Q4T. PC1Q2HT, PC1Q3T and PC1Q4T as the guest material, the efficient use of green materials F8BT as main material, preparation polymer light emitting diode device. Using PC1Q3T as the guest material prepared by the emission peak at 678nm, and color coordinates of (0.66,0.34) 2000cd m-2, close to the brightness of light emitting diode, deep red polymer external quantum efficiency of more than 1%. With PC1Q4T as the guest material prepared by the emission peak at 692nm, and color coordinates of (0.67,0.32) deep red, light emitting diode brightness close to 1500cd polymer m-2; emission peak at 708nm, and color coordinates of (0.69,0.31) 400cd, brightness of more than m-2, the external quantum efficiency of more than 0.6% of the near infrared polymer light emitting diode.
The design and synthesis of 4,7- -5,6- and [1,2,5] dibromo two chlorobenzene Thiadiazolen two triazole, and its receptor unit synthesis of conjugated polymer. The reactivity of the molecules in the chlorine and bromine atoms in the Stille reaction between small, can not be used as monomer for polymerization; it can be conjugated polymer backbone containing a chlorine atom by Suzuki polymerization. The chlorine atoms into the dibenzothiophene was two units, will make the LUMO level of polymer materials increased. The results of quantum, caused by chlorine atoms inferred regulation of the level in the system of quinoxaline and dibenzothiophene two triazole system as the reason for the difference may be electronic ability of quinoxaline and dibenzothiophene in two were: in the two ring and thiophene thiazole ring and steric differences. In two 4,7- (5- bromo -2- thienyl) -5,6- two and [1,2,5] two were for chlorobenzene thiazide receptor unit to unit was synthesized by 2,7- dual band which alcohol boric acid ester - fluorene The polymer PFC1DTBT as the object of materials with doping concentration of 3% to the main green materials in F8BT, prepared by the device structures of ITO/PEDOT:PSS (30nm) /F8BT: polymer (100nm) /Ca (20nm) /Al (100nm) polymer light emitting diodes, light emitting peaks are located at 632nm, and color coordinates of (0.60,0.40), maximum brightness can reach 15580cd m-2, the current efficiency was 1.2cd A-1 1.1%., the maximum external quantum efficiency
The bromine atom is introduced into the material of the side chain, by adjusting the proportion of bromine containing unit, synthesized a series of donor materials found in the polymer solution, the molar absorption coefficient is decreased first and then increased with the change of bromine containing ratio, increase the peak of fluorescence spectrum with bromine content gradually shift film; state, with the increase of the proportion of bromine, absorption peak of the more obvious, but the fluorescence spectra of the polymers are basically the same. This is because the bromine atom is polarized with the material of the dipole dipole interaction between polymer chains is weaker than the dipole dipole interaction. The weaker interaction between polymer chains between the grafting solution, after being polarized effect on the material of bromine atoms of side chains; but the film state, polymer chain interactions dominate. At the same time the introduction of molecular bromine atoms between weak interactions It is used to promote the accumulation of the material, so that the intensity of the acromion in the absorption spectrum is enhanced with the increase of the bromine content.

【学位授予单位】：华中科技大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：TQ317;TM914.4

【共引文献】