聚烯共价适应性网络,在再处理后完全恢复交叉链密度:通过自由基反应处理开发,使用共振稳定,芳香二硫化物交叉链接器进行自由基反应处理
Yen-Wen Huang1, Mathew J Suazo1, Stephanie M Barbon2
1Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, United States.
ACS macro letters
|March 5, 2025
概括
本研究引入了一种新的单步方法,用于在聚烯 (PP) 同聚合物中创建动态共价适应网络 (CAN). 这些先进的PP CAN证明了在多个加工步骤后的完全可回收性和财产恢复性.
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
- 可持续的高分子.
背景情况:
- 传统的聚烯 (PP) 缺乏动态共价交叉链,限制了其可回收和再加工能力.
- 适应性聚合物网络的开发对于创造可持续和可回收材料至关重要.
- 之前的方法无法在PP同聚合物中单步实现集成的,动态的共价交叉链.
研究的目的:
- 从聚烯 (PP) 同聚合物合成共价适应性网络 (CAN).
- 展示一个单步方法,在PP中创建动态共价交叉链接.
- 评估合成的PP CAN的可回收性和再加工稳定性.
主要方法:
- 在180°C使用基于基的方法对聚烯 (PP) 同聚合物进行反应处理.
- 结合了共振稳定,芳香二硫化物交叉链接剂 (基于甲基酸盐和基于基酸盐).
- 使用二甲基过氧化物 (DCP) 作为自由基启动剂,在存在不同PP分子量 (MW) 和DCP/交叉链接剂度的情况下.
主要成果:
- 通过基于甲基酸盐和基于基酸盐的二硫化物交叉连接剂成功合成了PP CAN.
- 在4 wt%的交叉连接器和4 wt%的DCP实现了网络形成,具有高MW PP (MFI=12).
- 基于烯酸的交叉链接器证明了在各种度和低MW PP (MFI=35) 中的网络形成.
- 最高交叉连接密度的PP CAN在三个压缩成型周期后显示了交叉连接密度的完全恢复.
- 在融挤出再加工后,在实验不确定性范围内观察到完全的交叉链密度恢复.
结论:
- 已经建立了一种简单的单步方法,用于在聚烯 (PP) 同聚合物中创建动态共价适应网络 (CAN).
- 合成的PP CAN表现出显著的再加工稳定性和完全可回收性,在多个循环后保持其交叉链密度.
- 这一进步为基于聚烯的材料提供了一个有前途的途径,以实现更可持续和循环的应用.
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