Hydration of Cyclic Oligo(oxyethylene) Compounds. Ultrasonic Velocities and Compressibilities of Binary Systems of Water with 12-Crown-4, 15-Crown-5, and 18-Crown-6

Abstract

Abstract Ultrasonic velocities of binary systems of water with 12-crown-4, 15-crown-5, and 18-crown-6 were measured and the adiabatic compressibilities were evaluated therefrom. The results indicate that the most compacted hydration structure is formed at the mole ratio, approximately 2:1, of water to oxyethylene monomer unit and that the poly(oxyethylene) chain enhances structuring of the liquid water network.