Thermotropic behaviour, self-assembly and photophysical properties of a series of squaraines
作者:Maher A. Qaddoura、Kevin D. Belfield、Paul Tongwa、Jessica E. DeSanto、Tatiana V. Timofeeva、Paul A. Heiney
DOI:10.1080/10610278.2011.622391
日期:2011.11.1
significant effect on both the thermotropic behaviour and the crystalline structure of the squaraine series. Two derivatives, butyl and heptyl, revealed the presence of liquid crystalline mesophases, smectic and nematic, respectively, which were confirmed and characterised via polarised light microscopy and X-ray diffraction. Several of the derivatives formed H- and/or J-aggregates upon thin film formation
一系列基于 2,4-双[4-(N,N-di-n-烷基氨基)-2-羟基苯基] 方酸菁的方酸染料,包括乙基、丙基、丁基、戊基、己基和庚基衍生物,通过以下方法合成相应的 4-(N,N-di-n-烷基氨基)-2-羟基苯酚与方酸缩合。使用热重分析和差示扫描量热法记录该系列的热行为,同时通过单晶 X 射线衍射阐明它们的晶体结构。事实证明,烷基链的长度对方酸系列的热致行为和晶体结构都有显着影响。两种衍生物,丁基和庚基,分别揭示了液晶中间相,近晶相和向列相的存在,通过偏光显微镜和X射线衍射证实和表征。如紫外-可见光谱所示,在热退火处理之前和之后,通过旋涂形成薄膜时,几种衍生物形成 H-和/或 J-聚集体。分子和晶体结构、聚集和热行为提供了对这类重要材料的超分子组装的深入了解。通过使这些衍生物成为许多电光和光子学应用的合适候选物,光物理测量揭示了大摩尔吸收率、相当高的荧光量子产率和显着的荧光各向异性。如紫外