在上循环过程中模拟塑料废物混合物的特性:一个实验评估
Annika Voelp1, Ali Bumajdad2, Sultan Majed Al-Salem3
1Chemical Analysis Division (Material Characterization), Thermo Fisher Scientific GmbH, Pfannkuchstrasse 10-12, 76185 Karlsruhe, Germany.
ACS omega
|February 10, 2025
概括
这项研究利用机械回收利用塑料废弃物转化为新材料. 三级混合物显示出更好的热稳定性,四级混合物则提供更好的机械性能,显示出可销售的可回收塑料的潜力.
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
- 可持续工程 可持续工程
背景情况:
- 全球原始塑料产量每年超过40亿,这给废物管理带来了重大挑战.
- 机械回收提供了一个可持续的解决方案,用于将塑料废物 (PW) 升级为增值材料.
- 聚烯聚合物,包括低密度聚乙烯和聚烯 (PP),是塑料废物的常见成分.
研究的目的:
- 研究模拟混合塑料废物的三元和四元混合物的机械和热性能.
- 评估加工条件,包括加热周期和干燥,对混合物特性的影响.
- 评估从回收聚烯中生产可销售的塑料等级的可行性.
主要方法:
- 使用双螺丝挤出制备低密度聚乙烯和聚烯的三元和四元混合物.
- 分析热稳定性,测热性能,表面形态和机械特性.
- 在不同的条件下处理的标本的评估,包括单次和双次加热周期 (HC) 和干燥.
主要成果:
- 三级混合物表现出比四级混合物更高的热稳定性,但机械强度较低.
- 在四级混合物中,添加聚烯稍微降低了开始温度.
- 融化温度在额外的加热周期和干燥过程中保持稳定,表明热性质得到保存.
- 三级混合物表现出一致的机械性能,而四级混合物在两个加热周期后表现出减少的断裂力和拉伸模量.
- 表面形态学显示,加热两个周期增加了洞穴形成,干燥时增加了光滑度.
结论:
- 机械回收是一种可行的方法,可以将混合塑料废物再循环到可销售的等级.
- 混合物成分显著影响热和机械性能,稳定性和强度之间的权衡.
- 加工条件,特别是重复加热周期,可能会影响回收聚烯混合物的机械性能.
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