不饱和聚酯/POSS取代苝酰亚胺荧光染料复合体系的光物理特性

Photophysical Properties of Unsaturated Polyester/Fluorescent Perylene Diimides Dye Substituted by Polyhedral Oligosilsesquioxane

通过分子结构设计抑制有机荧光染料在固态下的荧光淬灭,提高材料的发射效率是荧光功能材料领域的重要研究方向.采用溶液复合的方法将纳米颗粒笼状硅氧烷齐聚物(POSS)取代的苝酰亚胺荧光染料与不饱和聚酯(UPR)复合,应用紫外可见吸收光谱、荧光光谱方法比较分析了染料的双侧POSS取代(PPP)和另一侧为羟基取代(PPOH)的分子结构及其质量分数对复合薄膜光物理特性的影响.研究表明:PPP由于其两侧POSS的强耦合作用抑制了苝核通过连续π-π相互作用形成聚集,即使在PPP的质量分数达0.20%时,荧光量子产率仍可高达35%;PPOH则由于POSS的强耦合作用和羟基与UPR基体的氢键作用而有着更好的分散性.

Enhancement of quantum yield of fluorescent dyes under solid state by suppressing quenching via molecular structure design has attracted wide attention. Two typical perylene diimides substituted by polyhedral oligosilsesquioxane （POSS） at one side and POSS （PPP） or hydroxypropyl （PPOH） at another side, were composite to prepare unsaturated polyester （UPR） based films by solution blending method. Their photophysical properties were characterized by UV-vis and fluorescence spectroscopy. The research results show that quantum yield of films reach 35% even the weight concentration of PPP is as high as 0.20%, which is attributed to the π-π interaction between the dye molecules suppressed by the steric hindrance of POSS in two sides. The PPOH show good dispersity due to the steric hindrance of POSS and the hydrogen bond between hydroxy and UPR.