On the dependence of viscosity on temperature for liquids: A semi-empirical treatise

✍ Scribed by W. Fieggen

• Publisher: Elsevier Science
• Year: 2010
• Tongue: English
• Weight: 467 KB
• Volume: 89
• Category: Article
• ISSN: 0165-0513
• DOI: 10.1002/recl.19700890609

✦ Synopsis

Abstract

In this communication we introduce the viscosity‐temperature relation for liquids

which actually contains four independent constants. The equation is applied to literature data for water, ethanol, n‐butyric acid, aluminium isopropoxide, n‐octane, n‐eicosane, toluene and n‐decylbenzene. The mean error between observed and calculated viscosity values for the entire liquid range varies from 0.06% for n‐octane to 0.8% for toluene.

The equation is derived in an approximate way from the rate‐theory approach of Eyring, in which the liquids are assumed to have a quasi‐crystalline structure. We take into account a thermal expansion of the lattice, which influences the activation energy for viscous flow. The calculated values of the parameters are consistent with their physical meaning, with a possible exception for aluminium isopropoxide. The restrictions imposed by the theoretical model are discussed.