Formation and microstructure transition of F127/TX-100 complex

Area of Science:

• Polymer Science
• Supramolecular Chemistry
• Materials Science

Background:

• Triblock copolymer F127 and nonionic surfactant TX-100 are key components in self-assembly systems.
• Understanding their complex formation is crucial for designing advanced materials.
• Temperature and concentration significantly influence self-assembly behavior.

Purpose of the Study:

• To investigate the formation and temperature-induced structure transitions of F127/TX-100 complexes.
• To identify distinct concentration regions dictating complex behavior.
• To elucidate the role of TX-100 concentration in F127 aggregation and complexation.

Main Methods:

• Proton Nuclear Magnetic Resonance (1H NMR) spectroscopy.
• Dynamic Light Scattering (DLS) for size analysis.
• Isothermal Titration Calorimetry (ITC) for binding thermodynamics.

Main Results:

• Three TX-100 concentration regions exhibit unique temperature-dependent structural transitions.
• At low TX-100 concentrations, complexes transition from TX-100 micelle-templated to F127 micelle-templated structures.
• At high TX-100 concentrations, saturation occurs, leading to coexistence of free micelles and larger F127/TX-100 complexes.

Conclusions:

• The F127/TX-100 complexation is highly sensitive to both temperature and surfactant concentration.
• TX-100 acts as a template and can disrupt F127 aggregates, forming new complex structures.
• These findings provide insights into the design of stimuli-responsive materials based on polymer-surfactant interactions.