Periodic Expansion and Contraction Phenomena in a Pendant Droplet Associated with Marangoni Effect
A spontaneous oscillation between the expansion and contraction of a nitrobenzene pendant droplet containing di-(2-ethylhexyl)phosphoric acid (DEHPA) was observed in an aqueous phase under alkaline conditions. We described this phenomenon as the spontaneous oscillation of the oil–water interfacial t...
| Main Authors: | , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2021-12-01
|
| Series: | Materials |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1996-1944/15/1/239 |
| _version_ | 1797498470321356800 |
|---|---|
| author | Koutaro Onoda Ben Nanzai |
| author_facet | Koutaro Onoda Ben Nanzai |
| author_sort | Koutaro Onoda |
| collection | DOAJ |
| description | A spontaneous oscillation between the expansion and contraction of a nitrobenzene pendant droplet containing di-(2-ethylhexyl)phosphoric acid (DEHPA) was observed in an aqueous phase under alkaline conditions. We described this phenomenon as the spontaneous oscillation of the oil–water interfacial tension. The oscillation characteristics such as the induction period and the interfacial-tension oscillation frequency were investigated under different temperatures and aqueous phase polarities. The effects of the interfacial tension of the biphasic pendant-droplet, the surface excess of the surfactant molecules, and the amount of nitrobenzene elution from the droplet to the aqueous phase on the oscillation characteristics were investigated. Consequently, the periodic expansion–contraction oscillation mechanism was explained through the adsorption–desorption cycle of DEHPA with respect to the aggregate formation of the inverted micelle of DEHPA. This study was based on a simple vibration phenomenon of interfacial tension, and is extremely important for clarifying the predominant factors that cause fluctuations in the free interface energy, which has been ambiguous. |
| first_indexed | 2024-03-10T03:33:51Z |
| format | Article |
| id | doaj.art-798a56db900949db974cc4f234205800 |
| institution | Directory Open Access Journal |
| issn | 1996-1944 |
| language | English |
| last_indexed | 2024-03-10T03:33:51Z |
| publishDate | 2021-12-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Materials |
| spelling | doaj.art-798a56db900949db974cc4f2342058002023-11-23T11:50:22ZengMDPI AGMaterials1996-19442021-12-0115123910.3390/ma15010239Periodic Expansion and Contraction Phenomena in a Pendant Droplet Associated with Marangoni EffectKoutaro Onoda0Ben Nanzai1Department of Materials and Life Science, Faculty of Science and Technology, Shizuoka Institute of Science and Technology, 2200-2 Toyosawa, Fukuroi 437-8555, Shizuoka, JapanDepartment of Materials and Life Science, Faculty of Science and Technology, Shizuoka Institute of Science and Technology, 2200-2 Toyosawa, Fukuroi 437-8555, Shizuoka, JapanA spontaneous oscillation between the expansion and contraction of a nitrobenzene pendant droplet containing di-(2-ethylhexyl)phosphoric acid (DEHPA) was observed in an aqueous phase under alkaline conditions. We described this phenomenon as the spontaneous oscillation of the oil–water interfacial tension. The oscillation characteristics such as the induction period and the interfacial-tension oscillation frequency were investigated under different temperatures and aqueous phase polarities. The effects of the interfacial tension of the biphasic pendant-droplet, the surface excess of the surfactant molecules, and the amount of nitrobenzene elution from the droplet to the aqueous phase on the oscillation characteristics were investigated. Consequently, the periodic expansion–contraction oscillation mechanism was explained through the adsorption–desorption cycle of DEHPA with respect to the aggregate formation of the inverted micelle of DEHPA. This study was based on a simple vibration phenomenon of interfacial tension, and is extremely important for clarifying the predominant factors that cause fluctuations in the free interface energy, which has been ambiguous.https://www.mdpi.com/1996-1944/15/1/239pendant-drop methodself-oscillationMarangoni effectself-organizationinterfacial instability |
| spellingShingle | Koutaro Onoda Ben Nanzai Periodic Expansion and Contraction Phenomena in a Pendant Droplet Associated with Marangoni Effect Materials pendant-drop method self-oscillation Marangoni effect self-organization interfacial instability |
| title | Periodic Expansion and Contraction Phenomena in a Pendant Droplet Associated with Marangoni Effect |
| title_full | Periodic Expansion and Contraction Phenomena in a Pendant Droplet Associated with Marangoni Effect |
| title_fullStr | Periodic Expansion and Contraction Phenomena in a Pendant Droplet Associated with Marangoni Effect |
| title_full_unstemmed | Periodic Expansion and Contraction Phenomena in a Pendant Droplet Associated with Marangoni Effect |
| title_short | Periodic Expansion and Contraction Phenomena in a Pendant Droplet Associated with Marangoni Effect |
| title_sort | periodic expansion and contraction phenomena in a pendant droplet associated with marangoni effect |
| topic | pendant-drop method self-oscillation Marangoni effect self-organization interfacial instability |
| url | https://www.mdpi.com/1996-1944/15/1/239 |
| work_keys_str_mv | AT koutaroonoda periodicexpansionandcontractionphenomenainapendantdropletassociatedwithmarangonieffect AT bennanzai periodicexpansionandcontractionphenomenainapendantdropletassociatedwithmarangonieffect |