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The molar excess volume V E has been obtained trough the concentration range at 298.15 K for 41 systems composed of the series of glymes (oxaalkanes), CH 3 –O–(CH 2 –CH 2 –O) m –CH 3 with m =1 to 4 with normal, branched and cyclic alkanes. With literature values, a comprehensive view is given of (a) the change of equimolar V E with the molecular sizes of the components and with alkane structure and (b) concentration dependences which are S-shaped for certain systems. Equimolar H E were obtained at 303.15 K for 43 of the systems and used in applying the Prigogine–Flory (PF) theory to successfully predict the V E features. Evidence for association (Hydrogen bonding) in the pure glymes is reviewed. This accounts for discrepancies between PF theory and experiment which are minor for V E , but major for d V E /d T and C p E as seen through a consideration of literature values of these quantities. |
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