Interfacial and Bulk Behavior of Sodium Dodecyl Sulfate in Isopropanol−Water and in Isopropanol−Poly(vinylpyrrolidone)−Water Media

Abstract

The surface activity of isopropanol (IP) and poly(vinylpyrrolidone) (PVP) at the air/water interface has been studied. The self-aggregation of sodium dodecyl sulfate (SDS) in IP-water as well as in IP-PVP-water media has been investigated using physical methods, viz., tensiometry, conductometry, calorimetry, and viscometry. The interaction of SDS with PVP in IP-water medium as well as its self-aggregation (or micellization) in the presence of PVP has been assessed. The results reveal a fair degree of surface activity of IP in aqueous medium, which is only moderate for PVP. The critical micellar concentration (CMC) of SDS passes through a minimum at (v/v) % IP = 6.62. SDS interacts with PVP, yielding a critical aggregation concentration (CAC) at a low [SDS], independent of IP content in the medium. At a higher [SDS], free micelle formation takes place in solution, which is lower in mixed solvent than in water and is independent of solvent composition by tensiometry, but not by conductometry and calorimetry. The viscosity of micelle-interacted PVP in solution takes a long time to stabilize, whereas, for non-interacting additives, such as NaCl and cetyltrimethylammonium bromide (CTAB), it is time independent.

Kinetic study of styrene and methyl methacrylate emulsion polymerization induced by cumene hydroperoxide/tetraethylenepentamine

“…About 1.5 phm of SDS (1.5 parts per 100 parts of monomer) and 5 phm of isopropanol dissolved in 840 ml of DI water were charged into the reactor. Note that isopropanol behaves likes a cosurfactant when used below 6.62 % by volume in aqueous medium [17]. It helps to stabilize the emulsion polymerization by reducing the micellar surface charge density while forming mixed micelles with SDS, resulting in decreased counterion condensation.…”

Physicochemical Studies on the Interfacial and Bulk Behaviors of Sodium N‐Dodecanoyl Sarcosinate (SDDS)

“…In comparison, the spectroscopic method has produced lower CMCs than both conductometry and tensiometry. The CMC has been observed to be method dependent [13][14][15][16]. Different methods have different sensitivities for they sense different physical properties of the materials in solution.…”

Interaction of cationic hydroxyethylcellulose (JR400) and cationic hydrophobically modified hydroxyethylcellulose (LM200) with the amino-acid based anionic amphiphile Sodium N-Dodecanoyl Sarcosinate (SDDS) in aqueous medium

“…In the present system, the attractive electrostatic forces and the weak hydrophobic interaction operate in conjunction. With surfactant addition, the c decreased up to a certain [SDDS] called the critical aggregation concentration (CAC), beyond which small amphiphile aggregates (like micelles) continued to associate with the polymer segments (Dan et al, 2007(Dan et al, , 2009b. The CAC formation is a polymer induced amphiphile aggregation process.…”

“…In the realm of biology, the interaction process can be explored to immobilize enzymes to form polyelectrolyte complexes, and to purify proteins by selective coacervation (Margolin, Sherstyuk, Izumrudov, Zezin, & Kabanov, 1985). Different types of interaction are possible viz., between neutral polymer and nonionic surfactant (Feitosa, Wyn Brown, & Hansson, 1996), neutral polymer and anionic surfactant (Dai & Tam, 2001;Dan, Chakraborty, Ghosh, & Moulik, 2007;Griffiths et al, 2004), polyelectrolyte and surfactant of opposite charges (Exerowa, Kashchiev, & Platikanov, 1992;Sokolov, Yeh, Kohkhlov, Grinberg, & Chu, 1998;Tsekov & Ruckenstein, 1993), etc. In this discipline, interaction of biopolymers (polysaccharides, proteins, enzymes and DNA) with amphiphiles and lipids constitute a special category (Chatterjee, Moulik, Majhi, & Sanyal, 2002;Maulik, Dutta, Chattoraj, & Moulik, 1998;Mun, Rho, & Kim, 2009).…”