聚-2,7-烯在树突基质矩阵中的自我封装
D Marsitzky1, R Vestberg, P Blainey
1Contribution from the IBM Almaden Research Center, NSF Center for Polymeric Interfaces and Macromolecular Assemblies, 650 Harry Road, San Jose, California 95120-6099.
Journal of the American Chemical Society
|July 19, 2001
概括
研究人员使用宏观分子方法合成了树突性聚合物-2,7-烯聚合物. 树突侧组影响了结合和电子性质,在刚性杆聚合物中观察到第2代树突的最佳大小.
科学领域:
- 聚合物化学 聚合物化学
- 有机电子 有机电子
- 材料科学 材料科学 材料科学
背景情况:
- 刚性杆聚合物,如聚二二,具有出色的电荷传输特性.
- 控制聚合物形态和电子特征对于设备应用至关重要.
- 树突侧组可以影响聚合物溶解性,可加工性和光电子行为.
研究的目的:
- 合成和表征新型树突型多-2,7-同聚合物和共聚物.
- 研究树突侧组大小对聚合物结合和固态性质的影响.
- 评估这些新材料的光电子性能,包括电光发光.
主要方法:
- 2,7-二二烯单体的制备,具有不同代 (1, 2, 3) 的乙烯树枝.
- 凝聚聚合物化以制造与二甲基化的同聚合物和共聚合物.
- 使用光光谱学,固态光发光 (PL) 光谱,量子效率测量,原子力显微镜 (AFM) 和差分扫描热量计 (DSC) 的表征.
- 电流发光 (EL) 测量以评估设备的性能.
主要成果:
- 成功合成了树突型多-2,7-同聚合物和共聚合物.
- 光测量表明,在聚合物骨干沿着广泛的结合.
- 确定了树突侧组 (2 代) 的最佳大小,与结合链的高反应性和位点隔离相关.
- AFM和DSC证实,混合聚合物和共聚合物中没有微相分离.
- 同聚合物在最初的电发光测试中,与共聚物相比,呈现出更高的开启电压.
结论:
- 宏观体方法使得精确定义的树突型聚-2,7-烯材料的合成成为可能.
- 树突侧组工程提供了一条调整合聚合物的光电子特性的途径.
- 在这些刚性杆系统中,第2代树突侧组在平衡反应性和结合性方面似乎是最佳的.
- 合成的聚合物显示出在有机电子设备中的应用潜力,尽管需要进一步优化以减少开启电压.
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