ISSN:
1435-1536
Keywords:
Light scattering
;
micelles
;
rheology
;
photochemistry
;
solubilization
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract Viscosities, flow properties, and static low-angle light scattering of dilute (≤250 mmol/dm3) aqueous micellar solutions of cetyltrimethylammonium bromide were measured in the presence of various amounts of 9-anthrylmethanol (AM), 2,2,2-trifluoro-1-(9-anthryl)ethanol (TFAE), 1-(9-anthryl)ethanol (AE), 9-methylanthracene (MA), and 9-ethylanthracene (EA). At room temperature the solubilization of AM induces an increase of viscosity and a rise in aggregation numbers (as determined from low-angle light scattering). Both features are reverted upon in in situ photodimerization of AM. After lowering the temperaure, non-Newtonian flow is detected by means of a rotating viscometer. The solubilization of AE and EA, respectively, leads to analogous observations, while no viscoelastic features were obtained with solubilized MA. TFAE containing systems at room temperature show non-Newtonian flow accompanied by viscoelasticity which can be ascribed to the formation of long rod-like micelles. Raising the temperature as well as photodimerization diminish the lengths of the micelles and the non-Newtonian features.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01095063
Permalink