Programmable Morphology Evolution of Rod-Coil-Rod Block Copolymer Assemblies Induced by Variation of Chain Ordering

Area of Science:

• Polymer Science
• Materials Science
• Nanotechnology

Background:

• Block copolymer assemblies respond to external stimuli, but mechanisms are unclear, especially for rod-coil types.
• Understanding morphology transitions is key for designing advanced nanomaterials.

Purpose of the Study:

• To investigate the programmable morphology evolution of rod-coil-rod triblock copolymer assemblies.
• To elucidate the mechanism behind temperature-induced shape changes.

Main Methods:

• Synthesized rod-coil-rod triblock copolymers.
• Observed morphology transitions via temperature variation.
• Employed dissipative particle dynamics (DPD) simulations for mechanistic insights.

Main Results:

• A sequence of morphology transitions (ellipsoids to disks, bowls, vesicles) was observed with increasing temperature.
• Higher temperatures increased rod chain mobility and decreased rigidity.
• DPD simulations confirmed decreased chain ordering of rod blocks at higher temperatures drives the ellipsoid-to-vesicle transition.

Conclusions:

• Temperature-induced changes in rod chain dynamics and ordering control morphology transitions in rod-coil-rod triblock copolymers.
• This provides a mechanism for programmable nanoassembly construction.
• Findings guide the design of novel rod-coil block copolymer-based nanostructures.