Surfactant-Mediated Crystallization-Driven Self-Assembly of Crystalline/Ionic Complexed Block Copolymers in Aqueous...

Area of Science:

• Polymer Chemistry
• Materials Science
• Supramolecular Chemistry

Background:

• Block copolymers (BCPs) are versatile macromolecules capable of self-assembly into ordered nanostructures.
• The morphology of BCP assemblies is influenced by factors such as composition, molecular weight, and solvent environment.
• Controlling BCP self-assembly is crucial for developing advanced materials with tailored properties.

Purpose of the Study:

• To investigate the morphological transitions of crystalline/ionic complexed block copolymers (BCPs) in aqueous media.
• To explore the effect of Bis(2-ethylhexyl) sulfosuccinate sodium salt (AOT) as a surfactant on BCP self-assembly.
• To understand the mechanism of surfactant-induced morphological changes in BCP systems.

Main Methods:

• Synthesis of crystalline/ionic complexed block copolymers (BCPs) via sequential reactions.
• Characterization of BCP self-assembly and morphology in aqueous solutions.
• Addition of Bis(2-ethylhexyl) sulfosuccinate sodium salt (AOT) to induce and study morphological transitions.

Main Results:

• BCPs with varying hydrophilic fractions self-assembled into diverse morphologies like spindlelike, rodlike, and spherical micelles.
• The addition of AOT surfactant led to tight binding with cationic units, forming water-insoluble corona units.
• This binding reduced tethering density, inducing significant morphological changes from rods to platelets, fibrils, and dendrite-like micelles.

Conclusions:

• The study demonstrates the successful preparation of complexed BCPs with tunable self-assembly properties.
• Bis(2-ethylhexyl) sulfosuccinate sodium salt (AOT) effectively mediates morphological transitions in BCPs by altering corona properties.
• This provides a pathway for designing complex nanostructures with potential applications in nanotechnology and drug delivery.