Polymer CO2 Solubility. Structure/Property Relationships in Polyester Libraries

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• 作者：Christopher L. Bray ; Bien Tan ; Sean Higgins ; Andrew I. Cooper
• 刊名：Macromolecules
• 出版年：2010
• 出版时间：November 23, 2010
• 年：2010
• 卷：43
• 期：22
• 页码：9426-9433
• 全文大小：1023K
• 年卷期：v.43,no.22(November 23, 2010)
• ISSN：1520-5835

文摘

There is a need for continuing development of CO₂-soluble polymers to be used as suitable surfactants, ligands, or phase transfer agents in CO₂ solvent processes. Identifying CO₂/polymer solubility trends will help to enhance the search for CO₂-soluble polymers. The synthesis and characterization of structurally diverse polyester libraries using high-throughput techniques combined with the use of a high-throughput gravimetric extraction (HTGE) technique for the measurement of polymer solubility in supercritical carbon dioxide has enabled the study of structure/CO₂ solubility relationships. Small structural changes in polyesters have significant effects on their CO₂ solubility. Branching in either the diacid moiety or diol moiety imparts a significant increase in solubility, and in particular, branching with acyl chains enhances solubility by as much as 20 times. The length of the acyl chain is significant with the solubility of the polymer increasing in a systematic way as the acyl chain length increases to 10 carbon atoms. There are odd/even effects on solubility relating to the number of carbon atoms in the diacid moiety of the polyester. The results provide pointers for the development of more soluble alkyl polymers useful as ligands for synthesis and polymerization in CO₂. The use of HTGE to examine the effect of small structural changes on the solubility of polymers in CO₂ suggests that a quantitative study of structure−property relationships of polymers is possible, leading to the understanding and ability to predict solubility properties.