针线:HDPE/PP混合物的兼容性与布他烯衍生的聚烯块共聚合物
Liyang Shen1, Gabriela Diaz Gorbea1, Evan Danielson1
1Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN 55455.
概括
回收聚乙烯 (PE) 和聚烯 (PP) 是由于脆性混合物而具有挑战性的. 一种新的,廉价的块共聚合物添加剂使用工业方法创建了坚固,可回收的PE和PP混合物.
科学领域:
- 聚合物科学 聚合物科学
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 塑料废弃物管理是一个重大的全球挑战,特别是聚乙烯 (PE) 和异性聚烯 (iPP).
- 化混合PE和iPP用于回收往往导致由于相位分离和弱接口而易碎的材料.
- 目前用于改善混合物特性的区块共聚合物添加剂对于商品塑料来说是过于昂贵的.
研究的目的:
- 开发一个具有成本效益的区块共聚合物添加剂,以提高聚乙烯 (PE) 和异性聚烯 (iPP) 混合物的可回收性.
- 研究一种新的合成途径,用于生产PE和iPP混合区块共聚合物.
- 为了证明新添加剂在提高回收PE/iPP混合物的机械性能方面的有效性.
主要方法:
- 布他的阳离子聚合,然后进行催化化,以制造聚--乙烯) (E和X) 块.
- 一种EXE三块化共聚物的合成,其中E和X块与PE和iPP分别表现出选择性的混合性.
- 将PE和iPP与1重%的合成EXEtriblock共聚合物的融化混合,并随后对机械性能进行评估.
主要成果:
- 通过经济高效的工业方法制造的合成EXEtriblock共聚合物,有效地使PE和iPP混合物兼容.
- 含有1重%EXE的融混合混合物表现出与原始聚合物竞争的机械性能.
- 混合性归因于无形X块与iPP的界面纠以及E块与PE的联合结晶.
结论:
- 为了回收PE和iPP,已经开发出一种廉价且可扩展的工业生产块共聚合物添加剂 (EXE) 的方法.
- 该EXE添加剂显著提高了PE/iPP混合物的柔性和机械性能,解决了塑料回收的关键挑战.
- 这种方法为回收世界上两种最丰富的塑料提供了一种实用且经济可行的解决方案.
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