对于超临界二氧化碳的非离子表面活性剂的设计
1J. B. McClain, D. E. Betts, D. A. Canelas, E. T. Samulski, J. M. DeSimone, Department of Chemistry, University of North Carolina, CB 3290, Venable and Kenan Laboratories, Chapel Hill, NC 27599, USA. J. D. Londono, H. D. Cochran, G. D. Wignall, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA. D. Chillura-Martino and R. Triolo, Departimento di Chimica Fisica, University of Palermo, 90123 Palermo, Italy.
概括
新区块共聚合物双胞胎在超临界的二氧化碳 (CO2) 中自组成. 这些表面活性剂稳定了二氧化碳不溶性材料,为传统溶剂提供了更绿色的替代品.
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
- 绿色化学 绿色化学
背景情况:
- 区块共聚合物两活体是稳定乳液的关键.
- 超临界二氧化碳 (CO2) 是一种具有独特性质的环保溶剂.
- 在二氧化碳中分散不溶性物质是具有挑战性的,因为溶解度的差异.
研究的目的:
- 为了合成具有界面活性的区块共聚合物两.
- 为了研究它们在超临界CO2中的自我组装成小粒.
- 为有效的二氧化碳兼容表面活性剂制定设计标准.
主要方法:
- 聚乙烯-多聚合物的合成 (1,1-dihydroperfluorooctyl烯酸盐) 共聚物.
- 微角中子散射 (SANS) 用于研究菌形成和结构.
- 乳化实验以确定表面活性剂的容量.
主要成果:
- 在超临界CO2中,证明了块共聚合物的自我组装成核心菌体.
- 展示了这些非离子表面活性剂对高达20%的CO2不溶性碳化合物的乳化能力.
- 确认块段的不同溶解性驱动了微粒的形成.
结论:
- 开发了用于CO2的分子工程表面活性剂.
- 突出了表面活性剂修改的CO2在减少工业中溶剂废弃物的潜力.
- 建立了利用CO2作为分散的连续阶段的途径.
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