Short-term and long-term volatilities of films from polyol ester and ether-based oils of various molecular weights

Abstract

Viscosity and volatility parameters are very important for many technical applications, such as adhesives, lubricants or coatings. Often low viscosity and low volatility is desirable and various esters of oils from industrial crops are more appropriate than hydrocarbons. Short term evaporation can be quantified by thermogravimetric analysis (TGA), standard protocol of NOACK volatility or even flash point. But standardized tests of prolonged degradation do not address vaporization. In this study short and long-term volatilities of esters from industrial crops were compared to hydrocarbons and ethers using thin film methodologies. It turned out that mostly components of low molecular weight are responsible for NOACK results. Long term volatility is more dependent on decomposition reactions, which take place due to hydrolysis, oxidation and other degradation processes. Double bonds and ether linkages lead to higher long-term volatile emissions. Decomposition trends must be considered when selecting oils for applications, where low volatility and migration is important.