Polyelectrolyte‐micelle coacervation: effect of coacervate on the properties of shampoo

Abstract

A typical formula for shampoo containing cationic polymers and anionic/amphoteric surfactants exhibits liquid–liquid phase separation under certain conditions when the shampoo is diluted with water upon the actual use in bathroom. The lower dense phase is considered to be an insoluble complex formed with the cationic polymer and mixed surfactants. Generally, this associative liquid–liquid phase separation is called ‘coacervation’ and the phase of complex is called ‘coacervate’. Although it is well known that the usage texture of shampoo is influenced by coacervate, there are only a few reports about their relationship. In this work, we studied the properties of coacervate and its effect on the usage texture of shampoo, particularly focusing on the effect of the cationic polymer structure. We prepared five different model shampoos that contain various cationic polymers and studied the effect of the characteristics of the polymers on the condition of the complex formations, the amount of coacervate, the rheological properties and the adhesive behaviour of coacervate on the surface of damaged hair. It was found that both the structure and the degree of substitution of cationic polymer drastically changed the condition of coacervation. Moreover, the cationic polymers showed remarkable effect on the rheological properties and the adhesive behaviour of the coacervate on the damaged hair. These results implied that we could control the usage texture of shampoo by choosing proper cationic polymers to control coacervation.

Associative phase behaviour and disintegration of copolymer aggregates on adding poly(acrylic acid) to aqueous solutions of a PEO-PPO-PEO triblock copolymer

“…Derivation of eqn (7) Fig. A1 shows a cross-section of a hexagonal array of poloxamer rods of infinite length.…”

“…3 Associating mixtures of polymers and surfactants are also used in everyday products such as shampoos or fabric detergents to create beneficial surface layers on hair or fabric by surface deposition. 6,7 Also here, the size and long-range organization of the surfactant aggregates in the concentrated surface layer is of interest, since it may have important consequences for both molecular transport and mechanical properties of the layer.…”

Stimuli-Induced Nonequilibrium Phase Transitions in Polyelectrolyte–Surfactant Complex Coacervates

“…Polyelectrolyte−surfactant complexes (PESCs) are a wide class of colloidal systems where the surfactant's self-assembly is combined to the complexation properties of polyelectrolytes. 1−7 In the past three decades a large number of works has shown the interest of a wide community of scientists toward these systems for the broad set of applications in food science, 8 tissue engineering, 9 drug and gene delivery, 2,10 underwater adhesive conception, 11 structuring agents, 12 and water treatment, 13 but also personal care, cosmetics, 14 food, pharmaceutical science, 15−17 and many others. 5−7 The structure of PESCs depends on many parameters, including the intrinsic packing parameter of the surfactant, 18 rigidity of the polyelectrolyte, charge density and distribution on both the surfactant and polyelectrolyte, ionic strength, and pH, just to cite the main ones.…”

Salt-concentration dependence of the structure and form factors for the wormlike micelle made from a dual surfactant in aqueous solutions

“…3 of Hiwatari et al (2004)]. The surfactants are mixed together to tune detergency and other properties for final products.…”