软键的相对机械强度 在声化学聚合物机械化学中
Bobin Lee1, Zhenbin Niu1, Junpeng Wang1
1Department of Chemistry, Duke University , Durham, North Carolina 27708, United States.
Journal of the American Chemical Society
|August 7, 2015
概括
我们量化了三种聚合物键的机械强度. 亚博二基结是最弱的,其次是,然后是基,揭示了聚合物失效机制的洞察力.
科学领域:
- 聚合物化学
- 材料科学
- 机械化学
背景情况:
- 化学键的机械强度对于理解材料故障和机械化学反应性至关重要.
- 关于分离键的机械强度的定量数据,特别是在聚合物中,仍然很少.
- 了解机械应力下的结合裂变是设计坚固材料和响应系统的关键.
研究的目的:
- 确定含有亚博二基,和乙烯结合物的相对机械强度.
- 将这些键的机械强度与已知的热力学强度进行比较.
- 研究聚合物中的键结构,机械化学合和机械故障之间的关系.
主要方法:
- 通过聚合物溶液的脉冲超声波测定聚合物链裂变.
- 采用了两种互补的技术:在长时间的超声波下对非裂变机械体进行竞争性键裂和分子量分析.
- 用于内部校准机械力的二cyclopropane机械孔.
主要成果:
- 建立了一个明确的机械键强度等级:亚博二基 (最弱) < 乙烯 < 乙烯.
- 证明机械强度与热力学键强度没有直接关联.
- 观察到基乙烯键,尽管在热力学上比乙烯键更强,但具有更大的机械弹性.
结论:
- 聚合物中的分离键的机械强度受热力学稳定性以外的因素的影响,例如机械化学合效率.
- 机械化学合不良,可能是由于键裂过程中的再杂交,导致乙烯键的机械强度更高.
- 这项研究提供了关键的定量数据,用于预测在机械应力下聚合物的行为,并设计具有量身定制的故障特性的材料.
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