动力摩擦的温度依赖:塑料分类的手柄?
Joshua Thomas1, Chad R Snyder1, Kalman B Migler1
1Materials Science and Engineering Division National Institute of Standards and Technology.
Polymer engineering and science
|June 6, 2024
概括
塑料的摩擦性能可以用于机械回收的分类. 我们发现,聚烯和PET在点附近的动力摩擦显著增加,提供了一种新的分类方法.
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:
- 消费后塑料的机械回收 (PCR) 依赖于有效的分类,通常使用密度或光谱特性.
- 使用传统方法在高吞吐量下对聚烯片进行分类仍然具有挑战性.
- 关于塑料在接近点的温度下对塑料的摩擦的基础研究有限.
研究的目的:
- 调查使用温度依赖的摩擦性能来分类聚烯和PET的潜力.
- 探索替代密度和光谱特征为基础的塑料分类方法.
- 为聚合物在其软化/化模式中的三元学提供基本数据.
主要方法:
- 对高密度聚乙烯,低密度聚乙烯,聚烯和聚乙烯二甲 (PET) 的动力摩擦的温度依赖度的测量.
- 使用差分扫描热度计 (DSC) 和温度依赖的动态模量和探头杆测量.
- 专注于对所选聚合物的软化和化温度的实验.
主要成果:
- 对于聚烯,随着它们进入化/软化温度范围,观察到动力摩擦系数的显著增加.
- 对于PET而言,确定了动力摩擦的明显峰值,与其玻璃过渡和冷结晶相关.
- 在聚合物软化状态下观察到的摩擦系数与的摩擦系数相当.
结论:
- 取决于温度的摩擦为塑料,特别是聚烯和PET的机械回收分类提供了可行的替代性质.
- 在融和玻璃过渡点附近观察到的明显的摩擦行为为新的分离技术提供了机会.
- 在高温下对聚合物三元学的进一步研究可以提高回收效率和材料回收.
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