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首页> 外文会议>10th International Symposium amp; Exhibit on Supercritical Fluid Chromatography, Extraction, and Processing Aug 19-22, 2001 Myrtle Beach, SC USA >DESIGN OF NON-FLUOROUS, HIGHLY CO_2-SOLUBLE MATERIALS
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DESIGN OF NON-FLUOROUS, HIGHLY CO_2-SOLUBLE MATERIALS

机译：无氟高固溶性材料的设计

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摘要

The feasibility for use of carbon dioxide as a process solvent has been extensively investigated in both academic and industrial circles because CO_2 is an environmentally benign, non-flammable solvent. Solubility parameter calculations performed during the 1980's had suggested that CO_2's solvent power was similar to that of n-alkanes, leading to hopes that CO_2 could simply replace a wide variety of organic solvents. Although such solubility parameter values precluded the use of CO_2 for processing of polar materials, it was believed that addition of conventional alkyl-functional surfactants could effectively deal with the problem, as was the case for conventional non-polar solvents. However, early attempts to employ commercial surfactants in CO_2 failed owing to poor solubility of the amphiphiles, despite the fact that these same molecules exhibited adequate solubility in alkanes. It was ultimately learned that those solubility parameter calculations that indicated that CO_2 could replace alkanes are inflated by as much as 20% by the strong quadropole moment of CO_2. Johnston and colleagues subsequently suggested polarizability/volume as a better quantity by which to judge solvent power; by this standard CO_2 is a feeble solvent compared to short n-alkanes.
机译：在学术界和工业界都已广泛研究了将二氧化碳用作工艺溶剂的可行性，因为CO_2是一种对环境无害且不可燃的溶剂。在1980年代进行的溶解度参数计算表明，CO_2的溶剂能力类似于正构烷烃，因此人们希望CO_2能够简单地替代多种有机溶剂。尽管这样的溶解度参数值排除了使用CO_2来处理极性材料，但可以相信，与常规的非极性溶剂一样，添加常规的烷基官能表面活性剂可以有效地解决该问题。然而，由于两亲物的溶解性差，尽管这些相同的分子在烷烃中显示出足够的溶解性，但在二氧化碳中使用商业表面活性剂的早期尝试失败了。最终得知，那些溶解度参数计算表明，CO_2可以取代烷烃，而CO_2的强四极矩可将其膨胀多达20％。约翰斯顿及其同事随后提出了极化率/体积作为判断溶剂能力的更好方法。与短链正构烷烃相比，按照此标准，CO_2是微弱的溶剂。

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