Directional Supramolecular Polymerization in a Dynamic Microsolution: A Linearly Moving Polymer's End Striking...

Area of Science:

• Supramolecular Chemistry
• Materials Science
• Polymer Chemistry

Background:

• Directional chain reactions are common in nature but challenging in artificial self-assembly.
• Existing artificial one-dimensional self-assembling systems lack controlled directional growth.

Purpose of the Study:

• To develop a system for directional supramolecular polymerization using perylene bisimide (PBI) derivatives.
• To investigate the role of shear force in controlling polymer growth and enabling block copolymer synthesis.

Main Methods:

• Utilized perylene bisimide (PBI) derivatives as monomers in a microflow channel system.
• Investigated nucleation and growth dynamics under varying flow rates and shear stress.
• Employed in situ fluorescence spectra and linear dichroism to monitor polymerization.
• Applied the strategy to a two-monomer system for diblock copolymer formation.

Main Results:

• Spontaneous nucleation of PBI monomers was induced, facilitated by shear force.
• Shear stress selectively accelerated polymer growth at one end of oriented polymers.
• Directional growth predominated over free monomer nucleation.
• A diblock copolymer was successfully synthesized through selective reaction at the polymer terminus, forming a molecular heterojunction.

Conclusions:

• Friction-induced activation of a single polymer end enables directional supramolecular polymerization.
• This strategy is broadly applicable to directional supramolecular block copolymerizations.
• Allows for the precise formation of molecular heterojunctions in polymers.