封闭循环可回收和热超绝缘聚合石酸气凝的一步合成
Chang-Lin Wang1, Yi-Ru Chen1, Fabian Eisenreich1
1Polymer Performance Materials Group, Department of Chemical Engineering and Chemistry and Institute for Complex Molecular Systems (ICMS), Eindhoven University of Technology, Eindhoven, 5600 MB, The Netherlands.
Advanced materials (Deerfield Beach, Fla.)
|November 4, 2024
概括
新的聚胺酸 (PHT) 气凝提供了出色的绝热性能,并且可以通过化学回收. 这一突破使得从回收的单体中获得可持续的高性能材料成为可能.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物化学 聚合物化学
- 可持续化学 可持续化学
背景情况:
- 有机气凝是具有出色绝热性能的先进材料.
- 目前的有机气凝由于其不可回收性质而带来了环境挑战.
- 开发可回收,高性能有机气凝对于可持续性至关重要.
研究的目的:
- 合成用于封闭循环化学回收的新型聚胺酸 (PHT) 气凝.
- 评估这些PHT气凝的绝热,机械和化学性能.
- 为了证明回收PHT气凝和重复使用单体的可行性.
主要方法:
- 使用商用芳胺合成PHT气凝的一步凝结反应.
- 酸性水性条件用于PHT气凝的定量脱聚合.
- 材料属性的表征,包括导热性,机械强度,热稳定性和疏水性.
主要成果:
- 成功合成了具有超低导热率,高机械强度,热稳定性和疏水性的PHT气凝.
- 在酸性水性条件下实现了定量脱聚合,产生高纯度的单体.
- 回收的单体被用来制备新的PHT气凝,其性能与原始材料相似.
结论:
- 开发的PHT气凝为传统有机气凝提供了一个可持续的替代方案.
- 简单的一步合成和高效的闭环循环回收过程加速了可持续超绝缘材料的开发.
- 这项工作为环保,高性能有机气凝铺平了道路.
相关概念视频
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Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
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Polyesters are commonly prepared from terephthalic acid and ethylene glycol; the crude product is known as poly(ethylene terephthalate) or PET. However, polyesters are synthesized industrially by transesterification of dimethyl terephthalate with ethylene glycol at 150 °C. The two reactants and the polymer...