Enhancing covalent mechanochemistry in bulk polymers using electrospun ABA triblock copolymers

Area of Science:

• Polymer Science
• Materials Chemistry
• Mechanochemistry

Background:

• Mechanochemical activation of covalent bonds in bulk polymers typically shows low conversion rates.
• Understanding and enhancing polymer mechanochemistry is crucial for developing advanced materials.

Purpose of the Study:

• To investigate methods for enhancing the mechanochemical activation of gem-dibromocyclopropane (gDBC) mechanophores within a polymer matrix.
• To explore the effect of polymer architecture on mechanophore activation efficiency.

Main Methods:

• Synthesis of ABA-type triblock copolymers with a central poly(1,4-butadiene) (PB) block containing gem-dibromocyclopropane (gDBC) mechanophores and polystyrene (PS) end blocks.
• Characterization of the triblock copolymer structure.
• Electrospinning of the triblock copolymer to create aligned fiber mats.
• Assessment of mechanochemical activation under tension.

Main Results:

• The ABA triblock architecture significantly enhances the mechanochemical activation of gDBC mechanophores compared to bulk polymers.
• Electrospinning the triblock copolymer into aligned fiber mats further boosts activation, particularly under applied tension.
• The specific arrangement of polymer blocks influences the efficiency of mechanical bond breaking.

Conclusions:

• ABA triblock copolymers offer a promising strategy for improving polymer mechanochemical activation.
• Aligned polymer fibers produced by electrospinning can maximize mechanophore response.
• This work provides a pathway for designing polymers with enhanced mechanoresponsive properties.