宏观机械性能和可生物降解和不可生物降解聚合物的分子级热放松的相互关系
Shipra Bhatt1, Debjani Bagchi1
1Department of Physics, Faculty of Science, The Maharaja Sayajirao University of Baroda, Vadodara 390002, Gujarat, India.
Journal of physics. Condensed matter : an Institute of Physics journal
|September 25, 2024
概括
可生物降解的聚烯碳酸 (PPC) 显示了比HDPE和LLDPE更高的破裂延伸,但弹性模量较低. 与无形性相关的分子流动性决定了宏观的聚合物特性.
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
- 机械工程 机械工程
背景情况:
- 非生物降解的聚合物,如HDPE和LLDPE主导应用.
- 可生物降解的聚合物提供了可持续的替代品,但需要对性能进行评估.
- 了解结构属性关系对于聚合物开发至关重要.
研究的目的:
- 对聚烯碳酸盐 (PPC) 与HDPE和LLDPE的宏观机械性能进行比较分析.
- 研究机械和热应力对聚合物薄膜反应的影响.
- 为了将分子尺度的行为与宏观机械特征相关联.
主要方法:
- 对PPC,HDPE和LLDPE薄膜进行比较的拉伸应力测试.
- 对聚合物对热应激反应的分析.
- 拉曼光谱检测分子运动和放松过程.
- 分子参数 (峰值宽度) 和宏观性质 (YM,EB) 之间的相关性分析.
主要成果:
- 在破裂 (EB) 时,PPC的延伸度明显高于HDPE和LLDPE.
- 与HDPE和LLDPE相比,PPC具有较低的弹性模量 (YM).
- 塑料变形行为有所不同,PPC显示高原区域.
- 拉曼分析表明,PPC中增加了分子流动性,与较高的EB和较低的YM相关.
结论:
- 宏观聚合物的特性在很大程度上受分子级反应的支配.
- 在PPC中较高的无形性有助于增强分子流动性和延长,而牺牲了弹性模量.
- PPC具有独特的特性平衡,受其分子结构和移动性的影响.
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