在有机溶剂中高质量分散的hexabenzocoronene
J Marguerite Hughes1, Yenny Hernandez, Damian Aherne
1School of Physics & CRANN, Trinity College Dublin, University of Dublin, Dublin 2, Ireland.
Journal of the American Chemical Society
|June 22, 2012
概括
在溶剂中的赫克萨本佐可罗 (HBC) 分散取决于溶剂特性,最佳度在21 MPa的希尔德布兰德溶解度参数附近发现. 某些溶剂使单个HBC分子的高度成为可能,而不仅仅是聚合物.
科学领域:
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
- 超分子化学 超分子化学
背景情况:
- 赫克萨本佐科罗 (HBC) 是一种磁盘分子,在有机电子学中具有潜在的应用.
- 了解HBC在各种溶剂中的可溶性和聚合行为对于其加工和应用至关重要.
- 溶剂特性显著影响有机分子的分散和自我组装.
研究的目的:
- 为了研究hexabenzocoronene (HBC) 在广泛的溶剂中脱皮和分散.
- 为了将HBC的分散度和聚合状态与溶剂特性相关联,特别是希尔德布兰德溶解度参数.
- 建立用于量化HBC分散中的单个分子和总含量的指标.
主要方法:
- 在28种不同的溶剂中对HBC分散的系统研究.
- 吸收和光发光谱的分析以确定分子和聚合物含量.
- 分散性质与希尔德布兰德溶解度参数的相关性.
- 使用扫描道显微镜 (STM) 和传输电子显微镜 (TEM) 进行自组装结构的表征.
主要成果:
- 在溶剂中,HBC分散度最大化,Hildebrand溶解度参数接近21 MPa(1/2).
- 好的溶剂,如环基利 (CHP) 保持高度的单个HBC分子,而糟糕的溶剂,如四水 (THF) 促进聚合,即使在低度.
- 与胺溶剂相比,化溶剂中的HBC聚合对希尔德布兰德参数更为敏感.
- 确定了四种溶剂 (CHP,1-甲,1-甲,1,2,4-三二),它们既能使单个HBC分子的总度高,也能使单个HBC分子的数量大.
- STM和TEM发现了自组装的单层和与HBC单体或小聚合物相一致的石墨物体.
结论:
- 溶剂选择对于达到单个HBC分子的高度和控制聚合至关重要.
- 具有Hildebrand可溶性参数约为21 MPa ((1/2) 的溶剂对分散HBC.有希望.
- 这些发现为设计具有量身定制性质的可溶液加工的HBC基材料提供了基础.
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