通过结合实验和数值方法对热力学行为进行循环聚烯混合物的特性推进
Pei Hao1, Charmayne Siebers2, Kim Ragaert2
1Department of Materials, Textiles and Chemical Engineering (MaTCh), Mechanics of Materials and Structures (MMS), Tech Lane Ghent Science Park-Campus A, Ghent University (UGent), Technologiepark-Zwijnaarde 46, 9052 Ghent, Belgium.
Polymers
|April 27, 2024
概括
这项研究引入了一种新的方法来分析回收聚烯 (PO) 混合物,如聚乙烯 (PE) 和聚烯 (PP). 该技术准确地测量了它们的热力学行为,这对于改善塑料回收至关重要.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物工程 聚合物工程
- 回收技术的回收技术
背景情况:
- 通过浮动分类回收混合聚烯烯 (MPO) 废物正在获得引力.
- 难以准确地描述回收聚烯 (PO) 混合物的热力学行为.
- 现有的方法缺乏精度,无法捕捉回收塑料中的复杂机械反应.
研究的目的:
- 开发和验证用于评估PO混合物热力学性能的综合实验和数值方法.
- 准确确定回收高密度聚乙烯 (HDPE),聚烯 (PP) 和它们的混合物中的应力-张力关系和温度变化.
- 研究应变速率和温度,包括自加热和热软化,对混合物行为的影响.
主要方法:
- 使用高速立体声数字图像关联 (DIC) 系统进行精确的应变测量.
- 集成了一个红外摄像头,以捕捉热力学分析期间的实时温度变化.
- 使用统一的半晶聚合物 (USCP) 模型来简化分析,并专注于关键的热力学现象.
主要成果:
- 开发的方法准确地捕捉了PO混合物的复杂应力-应变行为和温度变化.
- 对曲扭曲的纠正使得高精度的应力-应变关系得以推导.
- 模型预测与实验观测非常相匹配,验证了分析自我加热和热软化方法.
结论:
- 综合实验-数值方法为回收PO混合物的热力学特性提供了新的见解.
- 这种方法对于推进混合聚烯废料的实际应用和循环利用至关重要.
- 准确的热力学数据将有助于改善可持续塑料的材料设计和加工.
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