Corresponding states relations of dimethylsiloxanes: comparison of short and long chain linear- and cyclic-dimethylsiloxanes

• Published in: Fluid phase equilibria 1997, Vol.128 (1), p.115-130
• Main Authors: Barbarín-Castillo, Juan-Manuel, McLure, Ian A
• Format: Article
• Language: English
• Subjects: Chemical thermodynamics; Chemistry; Corresponding states relations; Cycloalkanes; Exact sciences and technology; Excess volumes of mixing; General and physical chemistry; Linear- and cyclic-dimethylsiloxanes; Mixtures; Reduction parameters; Tetramethylsilane; Theory; Thermodynamic properties
• ISSN: 0378-3812; 1879-0224
• DOI: 10.1016/S0378-3812(96)03132-9

A previous analysis of the pressure-volume-temperature behaviour showed that the linear dimethylsiloxanes conform to a phenomenological principle of corresponding states resembling but not identical to that of the normal alkanes. A similar analysis for tetramethylsilane-regarded as the first member of the dimethylsiloxane homologous series: two cyclic dimethylsiloxanes, octamethylcyclotetrasiloxane and decamethylcyclopentasiloxane, and two polydimethylsiloxanes, one linear and one cyclic-confirms that they conform to a similar principle. The results are used to predict with fair success the excess volumes of mixing of a series of six related mixtures of cyclic substances-cyclohexane, cyclooctane and cyclodecane + either octamethylcyclotetrasiloxane or decamethylcyclopentasiloxane-and two linear + cyclic substance mixtures-either n-hexane or decamethyltetrasiloxane + octamethylcyclotetrasiloxane.