title: Gelation of Oil upon Contact with Water: A Bioinspired Scheme for the Self-Repair of Oil Leaks from Underwater Tubes.
abstract: Molecular organogelators convert oils into gels by forming self-assembled fibrous networks. Here, we demonstrate that such gelation can be activated by contacting the oil with an immiscible solvent (water). Our gelator is dibenzylidene sorbitol (DBS), which forms a low-viscosity sol when added to toluene containing a small amount of dimethyl sulfoxide (DMSO). Upon contact with water, DMSO partitions into the water, activating gelation of DBS in the toluene. The gel grows from the oil/water interface and slowly envelops the oil phase. We have exploited this effect for the self-repair of oil leaks from underwater tubes. When a DBS/toluene/DMSO solution flows through the tube, it forms a gel selectively at the leak point, thereby plugging the leak and restoring flow. Our approach is reminiscent of wound-sealing via blood-clotting: there also, inactive gelators in blood are activated at the wound site into a fibrous network, thereby plugging the wound and restoring blood flow.
authors.affiliation: Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, Maryland 20742, United States.
authors.forename: Hyuntaek
authors.initials: H
authors.lastname: Oh
authors.affiliation: Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, Maryland 20742, United States.
authors.forename: Nicholas
authors.initials: N
authors.lastname: Yaraghi
authors.affiliation: Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, Maryland 20742, United States.
authors.forename: Srinivasa R
authors.initials: SR
authors.lastname: Raghavan
mesh_terms: D032701:Biomimetics; D001777:Blood Coagulation; D004121:Dimethyl Sulfoxide / Q000737:chemistry; D005782:Gels / Q000138:chemical synthesis / Q000737:chemistry; D015394:Molecular Structure; D009821:Oils / Q000737:chemistry*; D012212:Rheology; D013012:Sorbitol / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry; D014050:Toluene / Q000737:chemistry; D014867:Water / Q000737:chemistry*
chemical_list: D005782:Gels; D009821:Oils; D014867:Water; D014050:Toluene; D013012:Sorbitol; C097391:dibenzylidene sorbitol; D004121:Dimethyl Sulfoxide