Journal of the Taiwan Institute of Chemical Engineers ( IF 5.7 ) Pub Date : 2019-10-29 , DOI: 10.1016/j.jtice.2019.10.012 Thu Thi Yen Le , Siam Hussain , Shi-Yow Lin
This study investigated the uniqueness of advancing contact angle (CA) by examining the evaporation process of a sessile drop of surfactant solution [sodium dodecyl sulfate (SDS), hexaethylene glycol monododecyl ether (C12E6) and Triton X-100 (TX-100)] on parafilm. The sessile drop was formed from a pendant drop that had reached its equilibrium surface tension in an atmosphere with ∼100% humidity. The relaxation of the drop profile and wetting diameter were recorded from the moment the drop touched the parafilm, and the data were then analyzed to determine the advancing CA. The results showed that for SDS solution drops, only one advancing CA was observed at each SDS concentration. However, the experimental data of TX-100 and C12E6 solution drops indicated the presence of two distinct regions that showed a near-constant CA with a quasi-equilibrium advance of the triple line; hence matching the definition of an advancing CA. The possibility of the existence of two advancing CA was further explored and the presence of two advancing CA for the sessile drops of TX-100 and C12E6 solution was verified by closely examining the advance of the triple line.
中文翻译:
表面活性剂溶液的无滴液滴前进接触角的唯一性研究
这项研究通过检查表面活性剂溶液[十二烷基硫酸钠(SDS),六甘醇单十二烷基醚(C 12 E 6)和Triton X-100(TX- 100)]。无蒂液滴是由悬垂液滴形成的,该悬垂液滴在湿度约为100%的环境中达到其平衡表面张力。从液滴接触封口膜的那一刻起记录液滴轮廓的松弛和润湿直径,然后分析数据以确定前进的CA。结果表明,对于SDS溶液滴,在每个SDS浓度下仅观察到一个前进的CA。但是,TX-100和C 12 E 6的实验数据溶液滴表明存在两个不同的区域,这些区域显示出一个接近恒定的CA,并具有三线的准平衡提前;因此与高级CA的定义匹配。进一步探讨了存在两个先进的CA的可能性,并通过仔细检查三重线的进展,验证了TX-100和C 12 E 6溶液的无滴液滴中存在两个先进的CA。