Related Experiment Video
Updated: Jul 9, 2026
06:31
Studying Surfactant Effects on Hydrate Crystallization at Oil-Water Interfaces Using a Low-Cost Integrated Modular Peltier Device
Published on: March 18, 2020
Polyelectrolyte-surfactant complexes with long range order
Isabel E Pacios1, Björn Lindman, Krister Thuresson
1Dep. Fisicoquímica (CTFQ), Facultad de Ciencias, Universidad a Distancia, 28040 Madrid, Spain. ipacios@ccia.uned.es
Journal of Colloid and Interface Science
|December 11, 2007
Summary
Carboxymethyl cellulose (CMC) and modified CMC form hexagonal precipitates with surfactants. Interactions depend on polymer structure, indicating hydrophobic chains may reside in aqueous regions.
Area of Science:
- Materials Science
- Polymer Chemistry
- Colloid Science
Background:
- Carboxymethyl cellulose (CMC) and its derivatives are widely used polymers.
- Surfactants are crucial in various industrial applications.
- Understanding polymer-surfactant interactions is key for material design.
Purpose of the Study:
- To investigate the phase behavior of carboxymethyl cellulose (CMC) or hydrophobically modified CMC with oppositely charged surfactants.
- To characterize the structure and composition of the formed precipitate.
- To elucidate the interplay between electrostatic and hydrophobic interactions.
Main Methods:
- Preparation of aqueous mixtures of CMC (or modified CMC) and benzyldimethyltetradecylammonium chloride.
- Characterization of the precipitate formed at specific polymer and surfactant concentrations.
- Analysis of precipitate composition, water content, and lattice parameter.
- Investigation of the influence of polymer/surfactant ratio on phase behavior.
Main Results:
- A precipitate with hexagonal order formed under specific conditions (0.18% polymer, high surfactant content).
- Precipitate composition remained relatively constant in water content but showed slight polymer decrease with varying surfactant content.
- Lattice parameter decreased with increasing polymer/surfactant ratio, faster for CMC than modified CMC.
- Interactions were non-additive, suggesting a dependence on the polymer's substitution degree.
Conclusions:
- Electrostatic and hydrophobic interactions in these systems are complex and non-additive.
- The degree of substitution in CMC significantly influences the interaction dynamics.
- Structural analysis suggests hydrophobic chains of modified CMC may extend into the aqueous phase within the hexagonal structure.
More Related Videos
Related Concept Videos
01:27Surface Active Agents
Surfactants, named for their behavior at interfaces, positively adsorb at the interfaces of two phases, reducing interfacial tension. Their versatility as emulsifiers, detergents, and foaming agents stems from this ability. Surfactants, often termed amphiphiles, share the property of amphipathy, with molecules having both hydrophilic and hydrophobic portions. The hydrophilic part is called the head, and the hydrophobic part, including an elongated alkyl substituent, forms the tail.Surfactants...
01:30Micelles
Micelle formation is an intricate process that hinges on the properties of amphiphilic or amphipathic molecules and the conditions of the system in which they are found. Amphiphilic molecules, which have both hydrophilic (water-attracting) and hydrophobic (water-repelling) parts, play a critical role in this process.In aqueous environments, these molecules arrange themselves such that their hydrophilic heads are turned towards the water phase, while their hydrophobic tails are oriented away...
03:22Colloids
Children at play often make suspensions such as mixtures of mud and water, flour and water, or a suspension of solid pigments in water known as tempera paint. These suspensions are heterogeneous mixtures composed of relatively large particles that are visible to the naked eye or can be seen with a magnifying glass. They are cloudy, and the suspended particles settle out after mixing. On the other hand, a solution is a homogeneous mixture in which no settling occurs and in which the dissolved...
03:00Solubility
Solution, Solubility, and Solubility Equilibrium
A solution is a homogeneous mixture composed of a solvent, the major component, and a solute, the minor component. The physical state of a solution—solid, liquid, or gas—is typically the same as that of the solvent. Solute concentrations are often described with qualitative terms such as dilute (of relatively low concentration) and concentrated (of relatively high concentration).
In a solution, the solute particles (molecules, atoms, and/or ions)...
A solution is a homogeneous mixture composed of a solvent, the major component, and a solute, the minor component. The physical state of a solution—solid, liquid, or gas—is typically the same as that of the solvent. Solute concentrations are often described with qualitative terms such as dilute (of relatively low concentration) and concentrated (of relatively high concentration).
In a solution, the solute particles (molecules, atoms, and/or ions)...
01:29The Colloidal State
The formation of a colloidal system is exemplified by an aqueous solution containing Cl− ions is introduced to another containing Ag+ ions, resulting in the precipitation of solid AgCl as extremely tiny crystals. Instead of settling out as a filterable precipitate, these crystals remain suspended in the liquid, showcasing a colloidal system.A colloidal system involves colloidal particles within the approximate range of 1 to 1000 nm in at least one dimension, dispersed in a medium called the...
03:13Intermolecular Forces
Atoms and molecules interact through bonds (or forces): intramolecular and intermolecular. The forces are electrostatic as they arise from interactions (attractive or repulsive) between charged species (permanent, partial, or temporary charges) and exist with varying strengths between ions, polar, nonpolar, and neutral molecules. The different types of intermolecular forces are ion–dipole, dipole–dipole, hydrogen bonds, and dispersion; among these, dipole–dipole, hydrogen bonds, and dispersion...