Physicochemical Investigations on the Interaction of Surfactants and Salts with Polyvinylpyrrolidone in Aqueous Medium

Effect of Head Groups, Temperature, and Polymer Concentration on Surfactant—Polymer Interactions

“…However no other study is available at lower concentrations for the comparison of data. Moreover, the use of different techniques (calorimetric and conductometric) may be another factor leading to difference in the observations as reported by Majhi et al [30]. As reported by these workers, CMC determined from calorimetric measurements is not affected by the presence of polymer; however, two breakpoints have been observed in the conductivity plots for same surfactants even in the lower concentrations of polymer and a slight decrease in CAC has also been reported.…”

“…As reported by these workers, CMC determined from calorimetric measurements is not affected by the presence of polymer; however, two breakpoints have been observed in the conductivity plots for same surfactants even in the lower concentrations of polymer and a slight decrease in CAC has also been reported. Calorimetry is an excellent technique to measure the enthalpy changes with high accuracy for any process, but here the possible reason for the difference in the results may be that the microcalorimetric technique is unable to detect the variation in CAC perhaps due to very low enthalpy values or because these are not well separated for detecting the change [30]. The concentrations of PEO have a very little effect on CAC values of SDBS as compared to SDS showing that SDS interacts strongly with PEO as compared to SDBS [12].…”

Aggregation of single-chained cationic surfactant molecules into vesicles induced by oligonucleotide

“…According to Fig. 1a, although the dilution enthalpy of the monomeric DEAB titration into water is very small (closed symbols), the enthalpy change is obvious when the monomeric DEAB is titrated into the oligonucleotide solution (open symbols) and the initial inflection is due to the electrostatic attraction between the positively charged DEAB and the negatively charged oligo(dC) 25 [30,31], indicating the aggregate formation along the oligonucleotide chain [30][31][32][33]. Thus, the cac of DEAB is 40 μM in the presence of oligo(dC) 25 .…”

Amphiphile self-aggregation: An attempt to reconcile the agreement–disagreement between the enthalpies of micellization determined by the van’t Hoff and Calorimetry methods

“…It is a dependable physical method to study the process of micellization [42]. There are numerous available literature that have used ITC for amphiphile aggregation [1][2][3][4][5]23,[31][32][33]35,[41][42][43][44][45][46][47], thermodynamics of bilayers-to-micelle transition [48,49], amphiphile interaction with polymers and macromolecules [50][51][52][53][54][55][56][57], characterization of protein solution [58], binding of small molecules with biopolymers [59][60][61], interaction of microemulsion with vesicles [62], determination of second virial coefficient of ionic liquid microemulsion [63], kinetics of reaction [64], etc. We have also used the method and have shown a general way of data treatment for microheterogeneous systems like micelles [65] and microemulsions [66].…”