The interactions of ι-carrageenan with cationic surfactants in aqueous solutions

Abstract

The interactions between the anionic polymer ι-carrageenan (IC) and the cationic surfactants 1-dodecyl-3-methylimidazolium bromide (C12mimBr), dodecyltrimethylammonium bromide (DTAB) and ethyl-α,ω-bis(dodecyldimethylammonium)dibromide (12-2-12) have been studied by fluorimetry and isothermal titration calorimetry. Our experimental results showed that at a low surfactant concentration, the monomers adsorbed on the IC chains through the electrostatic attraction, followed by the formation of induced micelles on the IC chains through the hydrophobic interaction until the IC chains are saturated by surfactant molecules; after that the added surfactant formed free micelles in the solution. A pseudo-phase-equilibrium thermodynamic model was proposed to explain the experimental results and to understand the mechanisms of the interactions in these three systems. Moreover, the salt effect on the interactions was investigated and found that it changed the critical concentrations but not the interaction mechanism.

Interactions between kappa-carrageenan and some surfactants in the bulk solution and at the surface of alumina

“…This finding is in agreement with the results obtained by Vinceković et al (2005) and Tomašić et al (2002) who also noticed that the effect of the carrageenan concentration on the cac and cmc values is very week. However, according to Bao et al (Bao et al, 2008) and Yin and co-workers (Yin et al, 2014) there is the influence of Carr concentration on the cac values. The last-mentioned authors explain this phenomenon with the fact that the increase of carrageenan concentration requires more surfactant molecules adsorbed on the polymer chain to form induced micelles.…”

“…As far as interactions between carrageenans and surfactants are concerned Yin and co-workers (Yin et al, 2014) studied the interactions between -carrageenan and some cationic surfactants. They found out that at a low surfactant concentration, the monomers adsorbed on the polymer chains through the electrostatic attraction, followed by the formation of induced micelles on the polymer chains through the hydrophobic interaction until the -carrageenan chains are saturated by surfactant molecules.…”

Study on the influence of surfactants on the adsorption and electrokinetic properties of the system: Cationic starch/alumina

“…It is well known that, the interaction between cationic polymer and the oppositely charged surfactant, evident from the pronounced lowering of the surface tension, can be detected at very low concentrations of surfactant [21,52]. Formation of polymer-surfactant complexes is controlled by both the electrostatic and hydrophobic interactions [53,54]. Fig.…”

Interactions and hybrid complex formation of anionic algal polysaccharides with a cationic glycine betaine-derived surfactant

“…After the polar head groups of cationic surfactant are bound to the totality of polymer sulfate groups, it is probable that associations occurred between surfactants bound to the polymer within the complex formed. It is also possible that associations between the surfactant/polymer complex structures operated in the solution through a reorganization of the complexes, as recently reported in the literature (Wang et al, 2014;Yin et al, 2014). Thus, in the case of dodecyltrimethylammonium bromide (DTAB)/()-carrageenan systems, Yin et al proposed a mechanism based on the rearrangement of the DTAB/polymer complex structure from lamellar-type structure to spherical-type structure prompted by the hydrophobic interactions.…”

“…For this reason, we used microelectrophoresis measurements, TEM and AFM in the case of -carrageenan to provide further insights into aggregation and binding interactions. Indeed, very few studies concerning the formation of complexes between -carrageenan (Lopez-Pena & McClements, 2014) and cationic surfactants were reported in the literature as it is the case forcarrageenan (Bonnaud et al, 2010;Gawel et al, 2013;Yin et al, 2014). Thus, microelectrophoresis measurements were not carried out for the two other carrageenans (i.e.…”