凝干燥方法对准备有不同网络形态的半晶体气凝特性的影响
Glenn A Spiering1, Garrett F Godshall1, Robert B Moore1
1Department of Chemistry, Macromolecules Innovation Institute, Virginia Tech, Blacksburg, VA 24061, USA.
Gels (Basel, Switzerland)
|June 25, 2025
概括
干燥方法显著影响聚合物气凝结构和特性. 开发类似支架的聚合物网络可以实现更简单的干燥技术,减少收缩并改善材料性能.
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
- 纳米技术 纳米技术
背景情况:
- 半晶体聚合物气凝具有独特的特性,但其加工具有挑战性.
- 干燥方法极大地影响气凝结构,毛孔大小和表面积.
- 了解结构属性关系是优化气凝制造的关键.
研究的目的:
- 研究真空干燥,冷干燥和超临界CO2提取对聚乙 (PEEK) 和聚乙烯硫化物 (PPS) 气凝的影响.
- 为了将气凝形态 (球状与状) 和聚合物类型 (PEEK与PPS) 与干燥后的结构变化和特性相关联.
- 为了确定这些聚合物气凝是否可以采用更简单的干燥方法.
主要方法:
- 制备PEEK和PPS气凝,具有球状或状形态.
- 使用真空干燥,冷干燥或超临界CO2提取气凝的干燥.
- 气凝结构的特征,包括收缩,中孔尺寸和表面积.
主要成果:
- 与超临界CO2提取相比,真空干燥导致了更高的收缩率,更小的半孔和更低的表面积.
- 冷干燥的气凝表现出中介性质.
- 有着像杆一样的特征和更高的网络连接性的气凝显示出增加的刚性和减少的收缩.
- 与PEEK气凝相比,PPS气凝具有更大的中孔和更小的表面积,导致收缩较少.
结论:
- 气凝网络连接性和形态学显著影响抗干燥引起的应力.
- 具有杆状特征的聚合物气凝可以使用更简单的蒸发干燥方法进行处理.
- 这项研究为更容易获得和更具成本效益的PEEK和PPS气凝生产铺平了道路.
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