延长诱导的度波动对聚合物混合物的细分摩擦的影响
Yangyang Wang1, Shalin Patil2, Shiwang Cheng2
1Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA. wangy@ornl.gov.
Soft matter
|May 17, 2024
概括
最近的研究表明,与经典理论相反,聚合物扩展性行为缺乏普遍性. 这项工作揭示了聚合物混合物中变形诱导的脱显著影响聚合物摩擦和非通用性行为.
科学领域:
- 聚合物物理 聚合物物理
- 类风病学 类风病学 类风病学
- 材料科学是一种材料科学.
背景情况:
- 经典的分子理论无法解释在线性聚合物中观察到的非普遍的扩展性行为.
- 聚合物和溶液的行为之间存在鲜明的对比,促使新的理论研究.
- 由于这些差异,诸如在拉伸的聚合物融中减少摩擦等概念已经出现.
研究的目的:
- 调查变形诱导脱混合在聚合物系统非通用延伸行为中的作用.
- 探索二元聚合物混合物的粘弹性不对称性如何影响宏观性质.
- 为了阐明度波动对聚合物细分摩擦在变形下的影响.
主要方法:
- 风湿学测量以探测延伸行为和粘弹性特性.
- 小角度中子散射 (SANS) 用于分析度波动和相位行为.
- 聚合物混合物的分析,包括聚钢/橄钢和聚钢/多钢 (α-甲基钢).
主要成果:
- 变形诱导的脱混合被认为是导致非普遍扩展行为的关键因素.
- 在聚乙烯/寡乙烯混合物中,除导致了有效的玻璃过渡温度的提高和明显的摩擦增强.
- 聚烯/聚烯 (α-甲基烯) 混合物表现出相反的行为,证明了脱的系统特定影响.
结论:
- 由粘弹性不对称性驱动的变形诱导脱混合对于理解非通用聚合物延伸流来说至关重要.
- 度波动显著影响聚合物细分摩擦,挑战现有的理论框架.
- 这项研究凸显了在聚合物变形过程中纳入微观结构变化的先进模型的需要.
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