Determination of Surface Tension of Succinonitrile Using a Surface Light Scattering Spectrometer

Abstract

Liquid/vapor interfacial surface tensions of succinonitrile, NC(CH2)2CN, were measured using noninvasive surface light scattering (SLS) spectroscopy. Succinonitrile (SCN) has been and is being used extensively in materials science and fluid physics research, for example, in several theoretical and numerical studies of dendritic growth. It is an established model material with several essential physical properties accurately known with the exception of the liquid/vapor surface tension, γ1v, at various temperatures. Using the SLS spectrometer, we have experimentally determined the liquid/vapor surface tension of SCN in the temperature range from just above its melting point (58.1°C) to 118°C using this noninvasive method. Previous measurements of SCN surface tension are extremely limited. To the best of our knowledge, this work is the first to measure the surface tension of succinonitrile noninvasively at melt and elevated temperatures. The SLS spectroscopy is relatively new and unique. This technique has several advantages over classical methods: it is noninvasive, has a good accuracy, and can be used to measure the surface tension and viscosity simultaneously, although the viscosity results are not discussed here. The accuracy of values obtained from this technique on some standard liquids is better than 2% for the surface tension and about 10 to 15% for viscosity. Our measurements gave γ1v=42.28−0.0629T±0.2 (mN·m-1), with T in °C, and the viscosity at 60°C is 2.68±0.3 cp for pure SCN.