窄带隙聚吡咯甲烷衍生物的制备与光学性能

Preparation and optical performance of narrow band gap poly(pyrrole methane)derivatives

由于高分子发光材料具有柔韧性好、合成简单、可大面积制备和使用寿命长等优点,成为近年来显示和照明领域的研究热点。本文以N-甲基吡咯和苯甲醛类为单体,采用缩聚法制备了3种可溶性、窄带隙、分子主链为部分共轭的聚吡咯甲烷衍生物,并利用红外光谱、紫外-可见光谱、荧光光谱、X射线衍射谱和热失重分析等方法对其结构、光致发光性质和热稳定性能等进行了测试分析,比较了大分子链上苯环对位取代基对材料发光性能的影响。研究结果表明,3种衍生物的热稳定性较好且具有部分结晶性,其光学禁带宽度均小于1.6 eV,属于窄带隙聚合物;在355 nm左右激发光下,3种衍生物均会产生约420 nm的发射光,为蓝紫色发光材料,且大分子链上苯环的对位取代基对该类材料的发光行为基本没有影响;在循环伏安曲线中,3种衍生物均存在较为明显的氧化还原峰。聚吡咯甲烷衍生物在光电器件材料方面有着潜在的应用价值。

Due to its advantages such as good flexibility,simple synthesis,large-area fabrication and long service life,polymer luminescent materials have become a research hotspot in the field of display and lighting in recent years.Three kinds of soluble,narrow band gap and partly conjugated poly(pyrrole methane)derivatives were fabricated via the polycondensation of N-methyl pyrrole and benzaldehyde.The structure,photoluminescence performance and thermal stability of the derivatives were investigated by FT-IR,UV-Vis,PL,XRD and TGA.Meanwhile,substituent effects of benzene ring on the luminescence properties of materials were compared.The results indicate that three derivatives had good thermal stability and partial crystallinity,and their optical band gaps are less than 1.6 eV,which belong to narrow band gap polymers.Under excitation at about 355 nm,three derivatives all produce emission light at about 420 nm,which are regarded as blue-purple luminescent materials.The contrapuntal substituents of the benzene ring on the macromolecular chain have negligible effect on the luminescence behavior.Furthermore,the redox peaks of three derivatives are observed clearly in the cyclic voltammetry curves.Therefore,the poly(pyrrole methane)derivatives are promising for potential application in photoelectric device materials.