通过形成二氧化玻罗兰和二氧化玻罗兰玻璃化物增强聚氨酸的特性
Sergei V Zubkevich1, Arpan Datta Sarma1, Oleg N Antzutkin2
1Luxembourg Institute of Science and Technology (LIST), Functional Polymeric and Particulate Materials Unit, 5 Avenue des Hauts-Fourneaux, Esch-sur-Alzette L-4362, Luxembourg.
Chemistry of materials : a publication of the American Chemical Society
|September 29, 2025
概括
聚氨酸 (PHUs) 通过使用1,4-二酸被修改成强大的玻璃剂. 这些新的PHU玻璃体表现出增强的机械性能,降低湿度灵敏度和改进的可回收性,克服了传统PHU的局限性.
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
背景情况:
- 聚氨酸 (PHUs) 为传统聚氨酸 (PUs) 提供了一个更绿色的替代品.
- PHUs的局限性包括低分子量,高水友性和显著的水吸收,阻碍了实际应用.
- 现有的线性和玻璃性PHU还没有完全解决这些缺点.
研究的目的:
- 通过开发强大的PHU玻璃仪来克服PHU的局限性.
- 增强粘弹性特性,降低PHU中的水分敏感性.
- 在新的PHU玻璃仪中研究结构-属性关系.
主要方法:
- 热塑性PHU的合链氧基与1,4-二酸.
- 合成PHU玻璃基的三个家族与使用芳香胺或亚利法胺的二氧化或二氧化部分.
- 使用固态核磁共振 (NMR) 光谱学来表征结构-属性关系.
主要成果:
- 由原子稳定的二氧化博洛干的PHU玻璃体表现出更好的热和水解稳定性.
- 酸形成N→B原键,增加玻璃过渡温度 (Tg) 并降低链的移动性.
- 与母PHU相比,观察到机械性能显著提高,包括拉伸强度增加 (+65-170%),破裂应变 (+125-300%) 和拉伸性 (∼4-11×).
- 在高湿度下,PHU玻璃保持着粘弹性特性.
- 开发的玻璃制剂可以在机械 (≥3×) 和化学上进行回收,而不会损失性能.
结论:
- 新型PHU玻璃剂成功合成,解决了传统PHU的主要局限性.
- 亚利法性氨基稳定型二氧化对增强热稳定性,机械性能和耐湿性至关重要.
- 这些坚固且可回收的PHU玻璃体对可持续的聚合物材料来说是一个重大进步.
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