The equilibrium and dynamic surface tensions of aqueous solutions of two newly synthesized surfactants relevant to wool dyeing were studied by means of the Wilhelmy plate and a bubble method. The surfactants (Nα,Nα′-bis(N-dodecyl-N,N-dimethylglycine cystine dimethyl ester dihydrochloride) and (Nα,Nα′-bis(N-dodecyl-N,N-dimethylglycine) cystamine dihydrochloride), are double-chain and bicationic in character. Their CMCs and Langmuir adsorption equilibrium parameters were determined at 25°C. Both molecules are very efficient surfactants. Their surface tensions equilibrate in time-scales ranging from seconds to hours (concentration c=1000-2 μM). Their dynamic surface tensions under constant and pulsating area conditions indicate that there is a strong barrier to adsorption at the air-water interface. The presence of the micelles accelerates the net rate of adsorption, suggesting fast micellar dissociation.
|Number of pages||7|
|Journal||Colloids and Surfaces A: Physicochemical and Engineering Aspects|
|Publication status||Published - 1994 Jul 29|
All Science Journal Classification (ASJC) codes
- Surfaces and Interfaces
- Physical and Theoretical Chemistry
- Colloid and Surface Chemistry