超支化聚合物的光物理行为及其压力效应  

High Pressure Effects on the Photophysical Properties of a New Type of Hyperbr anched Conjugated Copolymer

作　　者：钟波[1] 李沙瑜[1] 李竑[1] 何黎明[1] 白凤莲[1] 贺庆国[1] 杨国强[1] 

机构地区：[1]中国科学院化学研究所分子科学中心

出　　处：《化学学报》2002年第10期1768-1772,共5页Acta Chimica Sinica

基　　金：国家自然科学基金 (No .2 0 173 0 66);国家重点基础研究发展规划 (No .G2 0 0 0 0 7810 0 )资助项目 .

摘　　要：在溶液中观察到超支化聚合物 2 甲氧基 5 (2′ 乙基己氧基 ) 对 苯乙烯 /3,5 二乙烯基苯共聚体 (MEH PPV HS1)具有很强的荧光发射 ,并且在紫外区有两个明显的相邻吸收带 .分别激发这两个吸收带得到相同的荧光发射 .在压力作用下 ,这两个吸收带表现出不同的压力效应 ,并且在不同的压力下分别激发这两个吸收带时 ,所得到的荧光发射效率随压力的变化趋势表现出明显的不同 .结果表明 ,这两个相邻的吸收带分别来自于超支化聚合物分子中具有不同长短的有效共轭结构 .不同的共轭结构受光激发后到达不同的激发态 。Photophysical properties of a new hyperbranched conjugated copolymer, poly (2-methoxy-5-(2'-ethylhexoxy)-p-phenylene vinylene)-alt-(3,5-bisvinylicbenzene) (MEH-PPV-HS1), have been investigated. MEH-PPV-HS1 shows two adjacent absorption bands in UV region, and similar fluorescence emission spectra are obtained when it is excited selectively by these two bands. Effects of pressure on these two absorption bands are quite different and the emission intensity may change with pressure in a different way for excitation at different band. All these results indicate that these two absorption hands are attributed to different effective conjugated structures in MEH-PPV-HS1 respectively arid the selective excitation of MEH-PPV-HS1 generates different excited states, which transit to the same luminescent excited state by different relaxation pathway.

关 键 词：光物理行为 压力效应 超支化聚合物 3 5-二乙烯基苯 共聚体 2-甲氧基-5-(2'-2基己氧基)-对-苯乙烯 高分子半导体 

分 类 号：O631[理学—高分子化学]