在石墨烯和石墨烯氧化物上结晶和化聚合物链
Arman Ghasemi1, Yangchao Liao2, Zhaofan Li2
1Department of Mechanical Engineering, University of Texas at San Antonio, San Antonio, TX 78249, USA. wei.gao@tamu.edu.
Nanoscale
|July 5, 2023
概括
这项研究揭示了聚合物链极性和石墨烯基底如何影响结晶和化. 极性聚乙烯醇和非极性聚乙烯表现出不同的行为,石墨烯氧化物降低了结晶性.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物科学 聚合物科学
- 纳米技术 纳米技术
背景情况:
- 石墨烯和石墨烯氧化物 (GO) 是具有独特特性的先进材料.
- 了解二维材料上的聚合物行为对于开发新型复合材料至关重要.
- 极性显著影响分子相互作用和材料特性.
研究的目的:
- 在石墨烯和GO上研究极性 (聚乙烯醇,PVA) 和非极性 (聚乙烯,PE) 聚合物链的结晶和化.
- 量化基质特性和聚合物极性的对2D结晶的影响.
- 探索结晶聚合物链的融化行为与它们的分子量和极性相关.
主要方法:
- 使用了全原子 (AA) 分子动力学 (MD) 模拟.
- 开发了一个修改后的顺序参数来测量2D聚合物结晶.
- 模拟分析了结晶模式,由于氧化而减少的结晶性,以及融温度.
主要成果:
- 聚乙烯链形成圆形,折叠的状结构; 聚乙烯链形成延长的,直的图案.
- 石墨烯氧化物显著降低了PVA和PE的结晶性.
- 氧化群特征 (百分比,类型,分布) 影响了结晶模式.
- 聚乙烯的化温度高度依赖于分子量,而PE的化温度不那么敏感和较低.
结论:
- 基质特性和聚合物链极性极端地决定了结晶和融化行为.
- 定制基于石墨烯的聚合物异构结构需要考虑这些因素.
- 结果为设计具有特定性质的先进聚合物复合材料提供了洞察力.
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