Critical micelle concentration siloxanes

R. Wagner, Y. Wu, L. Richter, S. Siegel, J. Weissmuller, J. Reiners, Appl. Organometal. Chem., 1998, 12(12), 843-853. Silicon-modified carbohydrate surfactants IX dynamic wetting of a perfluorinated solid surface by solutions of a siloxane surfactant above and below the critical micelle concentration. ... 

Typical polymeric pseudostationary phases include micelle polymers, polymeric surfactants, water-soluble anionic siloxanes and dendrimers [223-231]. Micelle polymers [e.g. poly(sodium 10-undecylenate), poly (sodium 10-undecenylsulfate), poly(sodium undeconylvalinate), etc.] are synthesized from polymerizable surfactant monomers at a concentration above their critical micelle concentration. These polymers have similar structures to micelles without the dynamic nature of the micelle structure. Polymeric surfactants are polymers with surfactant properties [e.g. acrylate copolymers, such as 2-acrylamide-2-methyl-l-propanesulfonic acid and alkyl methacrylamide, alkyl methacrylate or alkyl acrylate, poly (ally lamine)-supported phases, poly(ethyleneimine), etc]. Water-soluble anionic siloxane polymers are copolymers of alkylmethylsiloxane... 

Extensively studied nonionic surfactants are PDMS / polyether block copolymers [31] and poly(ethylene oxide) substituted trisiloxanes [32-35]. They are able to achieve a maximum surface tension depression to about 21 mN/m and a low critical micelle concentration (CMC) [36], These siloxane surfactants can self-assemble into a variety of... 

In view of such applications, the adsorption of a grafted (rake-type) polymeric siloxane surfactant containing 48% PDMS, 39% PEO, and 13% PPO on carbon black particles dispersed in mixtures of water with polar organic solvents has been investigated [58]. The adsorption was foimd to obey the Langmuir isotherm below the critical micelle concentration and a sharp increase in the adsorbed amount was observed at higher surfactant concentrations. DLS and SANS data indicate that the structure of the adsorbed layer is similar to that of micelles. 

See Table 3.15 for isotherms of surface tension of KEP-2 (polyorgano-siloxane and polyoxyalkylene block copolymer) solutions in PTMG measured in the temperature interval of 323-353 K. The data presented in the table demonstrate that the critical concentration of micelle formation in such solutions is observed for a siu factant fraction around 2.5 x 10. ... 

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