Static and Dynamic Surface Tension of Ethoxylated Rapeseed Fatty Acid Methyl Esters

摘要

Rapeseed fatty acid methyl esters were ethoxylated at various temperatures (135-185°C range) with an average degree of ethoxylation equal to 10 and 15. Runs at higher temperatures resulted in products with a narrower range of ethoxylation. The composition of the products affected both the static and dynamic surface tension determined by the ring and bubble drop methods, respectively. The surface tension isotherms were approximated with the Szyszkowski equation, and appropriate adsorption parameters were determined and compared with those obtained for ethoxylated alcohols. Short- and long-term approximations gave different values of diffusivities but similar to those reported for ethoxylated alcohols.