区域随机和区域常规多的合成和表征 (poly{3-octylfuran)
J K Politis1, J C Nemes, M D Curtis
1Willard H. Dow Laboratory, Department of Chemistry, The University of Michigan, Ann Arbor, MI 48109-1055, USA.
Journal of the American Chemical Society
|July 18, 2001
概括
这项研究合成了具有不同区域规律性的聚3-八基,发现更高的区域规律性增强了合膜中的结晶性和电导率. 这些材料具有电子应用的潜力,因为它们具有可调节的电子特性和热稳定性.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物化学 聚合物化学
- 有机电子 有机电子
背景情况:
- 聚3-八) (P3OF) 是一种联聚合物,在有机电子中具有潜在的应用.
- 区域规律性显著影响联聚合物的特性.
研究的目的:
- 合成和表征具有不同区域规律性 (95%,75%,50%HT含量) 的聚3-八 furan.
- 调查区域规律性对P3OF的结构,光学,电子和热性能的影响.
主要方法:
- 在受控的区域规律性下合成P3OF.
- 用X射线衍射进行结构分析.
- 紫外线对光学属性的光谱学.
- 循环电压测量用于电化学性质.
- 片的电导度测量. 片的电导度测量.
- 对热稳定性的热重力测量分析.
主要成果:
- P3OF-95具有很高的结晶度,叶片间距为22.1 Å,π堆积为3.81 Å.
- 紫外线光谱显示P3OF-95中的聚合,显示Davydov分裂 (0.15 eV) 由于π系统相互作用.
- 在0.32V时,P3OF被反向氧化,在1.15V时发生不可逆转的氧化.
- 用添加的P3OF-95和P3OF-75薄膜的导电率分别为10−2 S/cm和10−7 S/cm.
- 估计的导电带间隙为P3OF-95的0.34 eV和P3OF-75.9的0.9 eV.
- 在中,P3OF样本在温度上稳定到380°C,但容易氧化.
结论:
- 在P3OF中较高的区域规律性导致合后的结晶性增加和电导率提高.
- 观察到的光学和电子特性与π系统堆叠的程度密切相关.
- P3OF表现出可调节的电子特性和良好的热稳定性,使其成为有机电子设备的有前途材料.
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