使用缺陷包含策略控制合聚合物中的链形状
Giannis Bounos1, Subhadip Ghosh, Albert K Lee
1Department of Chemistry and Biochemistry and the Center for Nano and Molecular Science and Technology, University of Texas, Austin, Texas 78712, USA.
Journal of the American Chemical Society
|May 27, 2011
概括
像MEH-PPV这样的合聚合物的缺陷会影响其光学性能. 线性缺陷保持了聚合物异质性,而曲或和的缺陷减少了它,导致各种链条配置.
科学领域:
- 聚合物化学 聚合物化学
- 材料科学 材料科学 材料科学
- 有机电子 有机电子
背景情况:
- 聚-2-甲基-5-2'-乙基基) -p-乙烯乙烯) (MEH-PPV) 是有机电子产品的关键合聚合物.
- 了解结构缺陷对聚合物特性的影响对于优化设备性能至关重要.
- 具有量身定制的骨干结构的新型MEH-PPV共聚物的合成和表征具有显著的兴趣.
研究的目的:
- 合成MEH-PPV的随机共聚合物,其中包含不同的脊柱指导单体.
- 研究各种类型的骨干缺陷对MEH-PPV的光物理性质的影响.
- 为了将结构缺陷与聚合物链形状和光学异构性相关联.
主要方法:
- 霍纳方法用于合成随机的MEH-PPV共聚物.
- 单分子偏振吸收光谱学用于研究聚合物异性质.
- 具有缺陷的模型PPV寡合物的分子动力学模拟.
主要成果:
- 维护PPV型聚合物的线性骨干的缺陷表现出高异构性,类似于无缺陷的MEH-PPV.
- 刚性,曲的缺陷降低了单链异构性.
- 和缺陷引入旋转自由,导致各种链条配置.
- 模拟显示线性和无缺陷的寡合物保持延伸,而曲和和的缺陷采用折叠的结构.
结论:
- 骨干缺陷的类型显著影响MEH-PPV的形状和光学特性.
- 线性缺陷有利于在合聚合物中保持理想的异构性质.
- 结构缺陷决定了聚合物链包装和有机电子产品的潜在应用.
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