多功能区块共聚物,作为循环辅助剂,通过原子转移激进聚合
Matylda Szewczyk-Łagodzińska1, Dawid Oleksiuk1, Sebastian Kowalczyk1
1Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664, Warsaw, Poland.
ChemSusChem
|November 17, 2023
概括
新的区块共聚合物作为聚酸 (PLA) 的多功能回收添加剂. 第一代添加剂改善了PLA的性能.
科学领域:
- 聚合物化学 聚合物化学
- 材料科学 材料科学 材料科学
- 可持续的塑料 可持续的塑料
背景情况:
- 开发有效的回收添加剂对于提高像聚乙烯 (PLA) 等回收聚合物的性能和可加工性至关重要.
- 现有的修饰剂在同时改善多种材料特性或在加工过程中保持稳定性方面经常面临局限性.
研究的目的:
- 合成新型区块共聚合物作为多功能回收添加剂用于聚酸 (PLA).
- 评估这些添加剂对PLA融粘度,材料稳定性,冲击强度和抗紫外线退化能力的影响.
- 研究两代合成添加剂的结构-性质关系.
主要方法:
- 第一个代块共聚合物的合成使用聚二醇,2,4-二异二二醇和一种新型的宏观发起剂.
- 将第一代添加剂修改为3,5-丁丁-4-基酸 (DHBA),以创建第二代反应性添加剂.
- 聚合物特性的表征,包括环氧基含量和环氧开放度.
- 添加剂通过挤出融并评估混合物特性 (融粘度,机械强度,紫外线稳定性) 加入到PLA中.
主要成果:
- 第一代添加剂增加了PLA的相对融粘度,稳定了性能,并增强了冲击强度.
- 第二代添加剂具有超过8%的环氧环开口,在机械性能方面表现下降.
- 第二代添加剂有效抑制了PLA混合板中的紫外线降解.
结论:
- 合成的区块共聚合物显示出作为PLA有效的回收添加剂的潜力,在加工性和耐久性方面提供了定制的改进.
- 修改程度 (环氧开口) 显著影响添加剂的性能,对于机械增强所需的最佳水平.
- 这些新型添加剂有望提高再生PLA材料的紫外线抵抗力.
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