Interactions between quaternized chitosan and surfactant studied by diffusion NMR and conductivity

Area of Science:

• Colloid and Surface Chemistry
• Polymer Science
• Analytical Chemistry

Background:

• Surfactant-polysaccharide complexes (SPEC) are vital in various industrial formulations.
• Understanding the interactions within these complexes is key to controlling formulation properties.
• Quaternized chitosan and sodium 1-decanesulfonate form oppositely charged SPEC.

Purpose of the Study:

• To characterize SPEC formed by sodium 1-decanesulfonate and quaternized chitosan.
• To compare the efficacy of conductivity and diffusion NMR (DOSY) in studying these complexes.
• To elucidate the interaction mechanisms between the surfactant and polysaccharide components.

Main Methods:

• Conductivity measurements were used to analyze surfactant-polysaccharide complexes.
• Diffusion NMR (DOSY) was employed for the first time to study these specific systems.
• Physico-chemical characteristics of pure solutions and complexes were determined.

Main Results:

• Conductivity and DOSY yielded comparable results for SPEC characterization.
• DOSY enabled simultaneous analysis of both surfactant and polysaccharide components.
• Detailed information on the nature and mechanism of surfactant-polysaccharide interactions was obtained.

Conclusions:

• DOSY is a powerful technique for investigating surfactant-polysaccharide interactions.
• Understanding these interactions is critical for optimizing industrial formulations.
• The study provides valuable insights for the development of advanced material formulations.