在α,ω-基碳酸的弹性模块中奇偶效应
Manish Kumar Mishra1, Sunil Varughese, Upadrasta Ramamurty
1Solid State and Structural Chemistry Unit and §Department of Materials Engineering, Indian Institute of Science , Bangalore 560 012, India.
Journal of the American Chemical Society
|May 22, 2013
概括
纳米沉积揭示了二碳酸中的弹性模量 (E) 在奇数和偶数链长度之间交替变化,反映了化温度 (Tm) 的变化. 这表明奇数二酸体中的分子应变会影响这两种特性.
科学领域:
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
- 纳米技术 纳米技术
背景情况:
- 二碳酸具有与其分子结构相关的独特物理特性.
- 在基碳酸中,化温度 (Tm) 呈现奇偶交替.
- 了解这些材料的机械性能对于各种应用至关重要.
研究的目的:
- 为了研究α,ω-基碳酸的分子结构和机械特性之间的关系.
- 探索弹性模量 (E) 的奇偶交替及其与融化温度 (Tm) 的相关性.
- 测试将分子菌株与观察到的交替联系起来的假设.
主要方法:
- 纳米缩技术被用来测量弹性模量 (E).
- 对一系列具有不同链长的α,ω-alkanedicarboxylic酸进行了研究.
- 分析的重点是将机械性能与热性能 (Tm) 相对应.
主要成果:
- α,ω-基碳酸的弹性模量 (E) 呈现出明显的奇偶交替.
- 这种弹性模量交替精确地反映了已知的化温度 (Tm) 奇偶交替.
- 奇数二酸体的弹性模量比偶数二酸体的弹性模量低.
结论:
- 观察到的弹性模量和化温度的奇偶交替是相关的.
- 奇数二酸体中紧张的分子构造被假定会导致较低的Tm和E.
- 减少奇数二酸体中的Tm的包装特征也促进了纳米缩过程中的变形适应,从而降低了E.
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