Foam Stability Mediated by Cellulose Nanocrystal-Anionic Surfactant Interactions.

Area of Science:

• Materials Science
• Colloid and Surface Science
• Sustainable Chemistry

Background:

• Anionic surfactants and cellulose nanocrystals (CNC) are key components in modulating aqueous system properties.
• Understanding their interactions is crucial for developing sustainable formulations in personal care, food, and household products.

Purpose of the Study:

• To investigate the interactions between CNC and anionic alkyl poly(ether) carboxylate surfactants.
• To elucidate how these interactions affect interfacial and foaming properties in aqueous systems.

Main Methods:

• Surface tension measurements
• Interfacial rheology
• Foaming tests
• Particle size analysis
• Zeta potential measurements
• Electron microscopy

Main Results:

• CNC slightly increased surfactant critical micelle concentration and reduced interfacial adsorption.
• CNC improved dispersion and aggregate formation with increasing surfactant concentration.
• Foamability was slightly reduced by CNC, but foam stability significantly increased at low surfactant concentrations due to CNC aggregation and network formation.
• Interfacial viscoelasticity increased, indicating stronger interfacial layers, especially at low surfactant concentrations.

Conclusions:

• CNC-surfactant interactions enable tunable control over interfacial structure and foam stability.
• The aggregation state of CNC is critical in determining foam properties.
• These findings provide valuable insights for designing greener formulations using CNC and surfactants.