聚亚苯基乙烯衍生物中溶剂诱导的共轭聚合物高分子线团与可逆超分子凝胶  

Solvent-induced Conjugated Polymer Coils and Reversible Supramolecular Gels in Polyphenylene Ethylene Derivatives

作　　者：张冬莲 何矩新 周学宏 郑楠 刘琳琳 解增旗 马於光 Dong-lian Zhang;Ju-xin He;Xue-hong Zhou;Nan Zheng;Lin-lin Liu;Zeng-qi Xie;Yu-guang Ma(Institute of Polymer Optoelectronic Materials and Devices,State Key Laboratory of Luminescent Materials and Devices,South China University of Technology,Guangzhou 510640)

机构地区：[1]发光材料与器件国家重点实验室华南理工大学材料科学与工程学院

出　　处：《高分子学报》2019年第12期1280-1289,共10页Acta Polymerica Sinica

基　　金：国家自然科学基金(基金号51873068,213334002,51573055,51521002);科技部国家科技计划(项目号2013CB834705,2015CB655003,2016YFB0401004)资助项目

摘　　要：通过引入与聚(2-(4-(3’,7’-二甲基辛氧基苯)-1,4-亚苯基乙烯)(P-PPV)主链亚苯基乙烯结构类似的R-limonene作为辅助溶剂,有效地实现聚合物链段的充分溶解和解缠结,并在此基础上成功制备了P-PPV的共轭高分子线团和可逆超分子凝胶.通过P-PPV的稀溶液旋涂薄膜的AFM图像,可以清晰地观察到纳米纤维形成的高分子线团及线团内部的精细结构. P-PPV在R-limonene的作用下,分子链从相互纠缠的状态发生解缠结作用,形成相互孤立的卷曲团,增强PLQY与荧光寿命.通过不同溶剂条件,得到了不同曲率的聚集体,对共轭高分子柔顺性有了进一步的认识.浓溶液下,P-PPV形成可逆的超分子凝胶,并具有良好的温度响应特性,凝胶生成区间在55~35℃.凝胶化的P-PPV是一种均匀的物理交联网络,使P-PPV的结构更为稳定,可以有效提升器件的稳定性、亮度和寿命.Good solubility is the premise in solution processing of conjugated polymers while strong π-πinteraction in the main chain is generally the main cause for bad dissolution. In this paper, our strategy is intruducing the auxiliary solvent and repeat unit with the similar structure as solvent in the main chain for good solubility of conjugated polymer. Based on the well dissolution between the auxiliary solvent and polymer repeat units induce a quasi-single polymer chain and advanced self-assembly, conjugated polymer coils and reversible supramolecular gels were acheived. R-limonene was added into chlorobenzene as the auxiliary solvent for the well solubility of poly(2-(4-(3’,7’-dimethyloctylo-xyphenyl)-1,4-pheny-lene-vinylene(P-PPV). Atomic force microscopy(AFM) images of the spin-coated films with solutions of low concentration showed the isolated P-PPV polymer coils and the fine structure inside the coils in chlorobenzene/R-limonene mixture;while with the absence of R-limonene, the packing of sub-polymer chain was clearly observed. In concentrated solution, P-PPV formed a reversible supramolecular gel at the concentration of 2 mg mL-1 with good temperature response characteristics in chlorobenzene/R-limonene mixture, and the gel temperature of P-PPV is in the range of 55 ℃ to-35 ℃. Aggregations with different curvatures were obtained in different solvents, which made us further understand the pliability of conjugated polymer. P-PPV molecular chains were dissolved by the enhanced solubility of alkyl sidechain and phenylene ethylene, that made it became pliable and then entangled, which allowed the assembly of polymer coils with high curvature and supramolecular gel with high ratio of solvent wrap.The fluorescence quantum yield and fluorescence lifetime were both improved in conjugated polymer coils and reversible supramolecular gels, but the physical cross-linking points by π-π interaction showed low energy level as those of charge trap sites, where the mobility became lower. In the organic light emitt

关 键 词：凝胶 共轭聚合物 聚合物发光二极管 链缠结 

分 类 号：TQ427.26[化学工程] TQ317