Process-directed self-assembly of block copolymers: a computer simulation study

Area of Science:

• Polymer Science
• Materials Science
• Chemical Engineering

Background:

• Block copolymer self-assembly is complex, with many stable states and slow structure formation.
• Controlling morphology requires either altering molecular structure or blending components.

Purpose of the Study:

• To explore process-directed self-assembly for controlling block copolymer morphology.
• To investigate trapping specific metastable states through rapid changes in thermodynamic conditions.

Main Methods:

• Simulations were used to model self-assembly kinetics.
• Comparison with free-energy techniques validated simulation results.

Main Results:

• Rapid changes (quenches) in thermodynamic conditions can reproducibly trap specific metastable morphologies.
• Controlling the initial unstable state is crucial for directing self-assembly towards desired structures.
• Non-equilibrium molecular conformations and local density conservation are important factors.

Conclusions:

• Process-directed self-assembly provides an alternative route to fabricating complex network structures.
• This method bypasses the need for extensive molecular engineering.
• Understanding non-equilibrium states is key to controlling self-assembly kinetics.