Synthesis and ordered aggregation in water of a blue light-emitting PEO-PHP-PEO triblock oligomer  

作　　者：HE Haifeng, CAO Hongqing, WAN Xinhua, TU Yingfeng, CHEN Xiaofang & ZHOU Qifeng Department of Polymer Science and Engineering, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China Correspondence should be addressed to Wan Xinhua (e-mail: [e-mail]) 

出　　处：《Chinese Science Bulletin》2003年第15期1525-1530,共6页

基　　金：supported by the National Natural Science Fundation of China(Grant Nos.29874003 and 29992590-4);the Teaching and Research Award Fund for Outstanding Young Teachers in Higher Education Institutions of the Ministry of Education of China.

摘　　要：A novel blue light-emitting coil-rod-coil triblock oligomer, PEO-PHP-PEO, which consists of para-hexaphenyl (PHP) as the rigid rod and poly(ethylene oxide) (PEO, M w = 750) as the flexible coil, has been synthesized. It is the first soluble poly(para-phenylene) molecule containing no lateral substituent, which can dissolve not only in organic solvents such as chloroform and THF, but also in water. The critical micelle concentration (CMC) of PEO-PHP-PEO in water is 5.25×10-4 mol·L-1 and the surface tension at CMC, 鉉MC, is 61.29 mN·m-1. The absorption peak of the molecularly dissolved PEO-PHP-PEO in water is centered at 323 nm and the fluorescence spectrum has a maximum at 432 nm and shows the vibronic fine structure typical of molecular dissolution. The photoluminescence spectrum of the aggregate solution is similar to that of the PHP polycrystal film, indicating that the ordered packing of PHP block has taken place due to a combination of hydrophobic interaction and p-p stacking. The oligomer self-assembles into cotton-like nanofibers with diameter of about 20 nm in 5.0×10-3 mol·L-1 aqueous solution.A novel blue light-emitting coil-rod-coil triblock oligomer, PEO-PHP-PEO, which consists of para-hexaphenyl (PHP) as the rigid rod and poly(ethylene oxide) (PEO, M w = 750) as the flexible coil, has been synthesized. It is the first soluble poly(para-phenylene) molecule containing no lateral substituent, which can dissolve not only in organic solvents such as chloroform and THF, but also in water. The critical micelle concentration (CMC) of PEO-PHP-PEO in water is 5.25×10-4 mol·L-1 and the surface tension at CMC, 鉉MC, is 61.29 mN·m-1. The absorption peak of the molecularly dissolved PEO-PHP-PEO in water is centered at 323 nm and the fluorescence spectrum has a maximum at 432 nm and shows the vibronic fine structure typical of molecular dissolution. The photoluminescence spectrum of the aggregate solution is similar to that of the PHP polycrystal film, indicating that the ordered packing of PHP block has taken place due to a combination of hydrophobic interaction and p-p stacking. The oligomer self-assembles into cotton-like nanofibers with diameter of about 20 nm in 5.0×10-3 mol·L-1 aqueous solution.

关 键 词：合成工艺 低聚物 聚乙烯 荧光光谱 PHP 对六苯基 

分 类 号：O631[理学—高分子化学]