Document Detail


Nonaqueous photorheological fluids based on light-responsive reverse wormlike micelles.
MedLine Citation:
PMID:  20030346     Owner:  NLM     Status:  PubMed-not-MEDLINE    
Abstract/OtherAbstract:
Fluids whose flow properties can be altered by light are an emerging class of functional materials, with potential applications in microscale actuators and valves. While many such photorheological (PR) fluids have been developed over the years, most are based on specialized organized molecules that require synthesis. We have instead sought to develop PR fluids using inexpensive chemical components that are commercially available, and this approach has been successfully applied to aqueous systems. Here, we demonstrate a simple class of nonaqueous PR fluids based on the phospholipid, lecithin, and the organic derivative, para-coumaric acid (PCA). The combination of lecithin with the trans form of PCA results in reverse wormlike micelles, which are long, flexible chains that undergo entanglement, thereby giving rise to viscoelastic fluids. Upon UV irradiation, trans-PCA is photoisomerized to its cis form, which has a lower polarity and hydrogen-bonding tendency. This causes a significant reduction in the length of the micellar chains, and in turn, the fluid viscosity drops more than 1000-fold. We show that photoresponsive reverse micelles can be formed in a range of organic solvents including cyclohexane, n-alkanes, alkenes, and fatty acid esters.
Authors:
Rakesh Kumar; Aimee M Ketner; Srinivasa R Raghavan
Related Documents :
2421656 - Dementias, psychological tests, and neurotransmitters.
3652986 - Ventral duplication of the autopod: chemical induction by methoxyacetic acid in rat emb...
826926 - Simultaneous determination of the three major monoamine metabolites in brain tissue and...
6821926 - Influence of phospholipid saturation on classical thin-layer chromatographic detection ...
8946726 - Potential interference by free fatty acids in determination of tricyclazole in brown ri...
22920386 - Synthesis of human milk fat substitutes from palm stearin with arachidonic and docosahe...
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  Langmuir : the ACS journal of surfaces and colloids     Volume:  26     ISSN:  1520-5827     ISO Abbreviation:  Langmuir     Publication Date:  2010 Apr 
Date Detail:
Created Date:  2010-04-13     Completed Date:  2010-07-01     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  9882736     Medline TA:  Langmuir     Country:  United States    
Other Details:
Languages:  eng     Pagination:  5405-11     Citation Subset:  -    
Affiliation:
Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, Maryland 20742-2111, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Water-Controlled Regioselectivity of Pd-Catalyzed Domino Reaction Involving a C-H Activation Process...
Next Document:  Autonomous Motion of Vesicle via Ion Exchange.