Self-inverted reciprocation of an oil droplet on a surfactant solution. Issue 18 (24th April 2017)

• Record Type: Journal Article
• Authors: Satoh, Yusuke; Sogabe, Yoshimi; Kayahara, Katsuhiko; Tanaka, Shinpei; Nagayama, Masaharu; Nakata, Satoshi
• Is Part Of: Soft matter. Volume 13:Issue 18(2017)
• Page Start: 3422
• Page End: 3430
• Publication Date: 2017-04-24
• Subjects: Soft condensed matter -- Periodicals; 530.413
• DOI: 10.1039/c7sm00252a
• Languages: English
• ISSNs: 1744-683X

Abstract

Abstract : A butyl salicylate (BS) droplet on a sodium dodecyl sulfate (SDS) aqueous phase spontaneously reciprocated even without the effect of boundary. The features of motion of the BS droplet changed depending on the concentration of SDS. Abstract : Self-motion of an oil droplet was investigated on a sodium dodecyl sulfate (SDS) aqueous phase. With an increase in the concentration of SDS, the nature of self-motion of a butyl salicylate (BS) droplet as the oil droplet was changed, i.e., no motion, reciprocation with a small amplitude, and reciprocation with a large amplitude, which was a value close to the half-length of the chamber. The interfacial tension, contact angle, and convective flow around the droplet were measured to clarify the driving force of reciprocation. The mechanisms of two types of reciprocation and mode-change were discussed in terms of the adsorption of SDS molecules at the BS/water interface and the dissolution of a mixture of BS and SDS into the bulk phase, the convective flow, and the Young's equation. The features of reciprocation and mode-change depending on the concentration of SDS were qualitatively reproduced by numerical calculation based on an equation of motion and the kinetics of SDS and BS at the air/aqueous interface.