Dynamics in a photoresponsive surfactant system

The study of surface tension and other surface properties is motivated by the large number of industrially relevant processes involving interfaces, such as coating, detergency, printing, foams, and so forth. These surface properties become increasingly important as the length scale of the system is reduced (as in microfluidic devices). Recently, much research has been focused on developing surfactants which respond to a particular stimulus (such as temperature, pH, light, etc.), so that properties such as surface tension and viscosity can be controlled using a convenient external trigger. Using light for this purpose has some advantages over other methods, as light can easily be focused and patterned (using optical lenses, filters, and masks) to give excellent precision for changing solution properties in a targeted area. A nonionic photoresponsive surfactant has been developed which incorporates the light-sensitive azobenzene group into its hydrophobic tail. Cis-trans photo-isomerization of this group causes a change in the structure of the surfactant molecule which alters its aggregation state in bulk solution and its adsorption capacity at an air-water interface.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Chemical Engineering.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2007

Author dc:creator

• Cicciarelli, Bradley A. (Bradley Adam)

Advisor dc:contributor.advisor

• T. Alan Hatton and Kenneth A. Smith.

• Chemical Engineering.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/39349
• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Identifier URI

http://dspace.mit.edu/handle/1721.1/39349

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/39349