Solubility of Silicone and Fluoro Compounds

The solubility of PDMS in COo /toluene mixtures has been attributed to comparable solubility parameters and the interaction between CO2 (a weak Lewis acid) and the strong electron donor capacity of the siloxane group. The oxygen in perfluoropolyethers also has an electron donor capacity. The solubility parameter 

The addition of small quantities of cosolvents, also known as modifiers or entrainers, can enhance the solubility characteristic further. Even though in earlier years attention was focused primarily on single-processing fluids such as CO2 and extractions as the primary mode of application, in recent years emphasis has been shifting to binary and multicomponent fluids and processes with a greater degree of complexity, which can include either physical or chemical transformations. Some modifiers with their relevant properties are listed in Table 3.2. 

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