Preparation Of Phthalocyanine-containing Polymers And Investigation On Their Properties

Phthalocyanines (Pcs) have received considerable attentions due to their uniqueoptical and electronic properties which give rise to the application of Pcs in variousdomains, such as organic filed effect transistors, optical information storage, organic solarcells, photodynamic therapy, nonlinear optical materials and so on.Phthalocyanine-containing polymers combine the excellent physical and chemicalproperties of Pcs and the good solubility and processability of polymers, which arebecoming one of research hotspots. In addition, the physical and chemical properties ofPcs-based materials can be further improved by self-assembly of Pcs to supramolecularstructures, which is a key issue for incorporating Pcs into molecular devices. Therefore,design and synthesis of phthalocyanine-containing polymers with novel structures andsuperior properites, and controlled organization of Pcs is one of the important researchsubjects in Pcs-based materials field.In this thesis, we designed and synthesized several phthalocyanine-containingpolymers with special structures. And the self-assembly, optical and electronic propertiesof Pcs-based materials were also investigated. The detailed researches were summarized asfollowing:(1) A benzenedinitrile functionalized monomer,2-methyl-acrylic acid6-(3,4-dicyano-phenoxy)-hexyl ester (MADCE), was successfully polymerized via thereversible addition-fragmentation chain transfer (RAFT) method. The polymerizationbehaviour conveyed the characteristics of “living”/controlled radical polymerization: thefirst-order kinetics, linear increase of number-average molecular weight with monomerconversion, narrow molecular weight distribution and successful chain-extensionexperiment. The soluble Zn(II) phthalocyanine (Pc)-containing (ZnPc) polymers wereachieved by post-polymerization modification of the obtained polymers. The Zn(II)phthalocyanine-functionalized polymer was characterized by FT-IR, UV-vis, fluorescence,atomic absorption spectroscopy and TGA analysis. The potential application of above ZnPc-functionalized polymer as an electron donor material in bulk heterojunction organicsolar cell was studied. The device with ITO/PEDOT:PSS/ZnPc-Polymer:PC61BM/LiF/Alstructure provided a power convergent efficiency (PCE) of0.014%, fill factor (FF) of0.24,open circuit voltage (Voc) of0.21V, and short circuit current (Jsc) of0.28mA/cm2.(2) Two soluble phthalocyanine compounds, fluorogalliumtetra-tert-butylphthalocyanine (ttbPcGaF) and its precursor hydroxygalliumtetra-tert-butylphthalocyanine (ttbPcGaOH) were successfully synthesized. ttbPcGaF had amuch stronger ability than that of ttbPcGaOH to self-organize into well-orderedone-dimensional (1D) supramolecular polymers in solid state as revealed by ESI-TWIMMS, UV-vis, WAXS and TEM measurements. The photovoltaic properties of ttbPcGaF andttbPcGaOH as electron donor materials in solution-processed Bulk Heterojunction (BHJ)organic solar cells (OSCs) were investigated, respectively. Due to the retention of theself-assembly property of ttbPcGaF in the ttbPcGaF:PC61BM blend film, thettbPcGaF-based BHJ OSC provided a profoundly improved power conversion efficiency(PCE) of0.41%. In contrast, ttbPcGaOH-based BHJ OSC only exhibited a low PCE of0.03%, because PC61BM prohibited the self-assembly of ttbPcGaOH into orderedsupramolecular structures in ttbPcGaOH:PC61BM blend film.(3) A new azobenzene-linked bisphthalontrile monomer (AzoBEDN) was synthesizedfor the first time. And the azobenzene-containing hyperbranched zinc phthalocyanine(AzoHBZnPc) were prepared by tetracyclomerization of AzoBEDN in high boiling pointsolvent. The formation of ZnPc in AzoHBZnPc and the photophysical and thermalproperties of AzoHBZnPc were investigated by FT-IR, UV-vis, PL and TGA measurements.The content of ZnPc in AzoHBZnPc was calculated by UV-vis spectroscopy and confirmedby atom absorption spectroscopy, respectively. The results indicated that the contents ofZnPc in AzoHBZnPc increased with the reaction time. The reversible trans-cis-transphotoisomerization of azobenzene units in AzoHBZnPc could take place under theirradiation of light with different wavelengths. Besides, the dielectric responses ofAzoHBZnPc were also studied. The dielectric constants of AzoHBZnPc were in the rangeof2.87and3.12, and the dielectric losses were below0.014.(4) A novel azobenzene (Azo) monomer (azobenzene-4,4’-diboronic acid) wassynthesized and employed as building block to produce Azo-containing covalent organicframeworks (Azo-COF) through the borate ester formation reaction with 2,3,6,7,10,11-hexahydroxytriphenylene under solvothermal condition. The obtainedAzo-COF exhibited high crystallinity, thermal stability and permanent porosity as revealedby PXRD, SEM, TEM, TGA and nitrogen sorption isotherm measurements. Thetrans-to-cis photoisomerization of Azo units in Azo-COF occurred under the radiation with365nm UV light. Most interestingly, the phoisomerization of Azo units only coulddecrease the crystallinity of Azo-COF, while could not change the pore size of Azo-COF.The successful construction of Azo-COF will provide the foundation of research for thesubsequent azobenzene-containing Pc COF.