Modular addition strategy-regulated polymerization-induced self-assembly: an in silico experiment

Area of Science:

• Polymer Chemistry
• Materials Science
• Supramolecular Chemistry

Background:

• Polymerization-induced self-assembly (PISA) is a powerful technique for creating complex polymer nanostructures.
• Controlling reaction kinetics and self-assembly morphologies in PISA remains a challenge for precise structure fabrication.

Purpose of the Study:

• To introduce and validate a modular addition strategy for regulating PISA reaction kinetics and self-assembly outcomes.
• To investigate the impact of different modular addition strategies on polymer block characteristics and final nanostructure formation.

Main Methods:

• In silico experiments were conducted on a well-established PISA system.
• Two modular addition strategies were investigated: multistep addition and constant rate addition of macromolecular chain transfer agents (macro-CTAs).
• Analysis focused on molecular weight distribution control and resulting self-assembled morphologies.

Main Results:

• Modular addition of macro-CTAs effectively controlled the molecular weight distribution of the hydrophobic polystyrene (PSt) block.
• This control resulted in the formation of vesicle structures with irregular, aspherical cavities.
• A novel vesicle formation pathway was identified, involving initial small vesicle generation followed by gradual growth.
• Increasing macro-CTA addition rate in constant rate strategy shifted morphology from micelles to vesicles.

Conclusions:

• Modular addition strategies offer effective control over PISA kinetics and resultant nanostructures.
• The findings provide insights into vesicle formation mechanisms and morphology transitions in PISA.
• This work can guide the development of advanced experimental techniques for PISA systems.