Mechanophores with a reversible radical system and freezing-induced mechanochemistry in polymer solutions and gels

Keiichi Imato, Atsushi Irie, Takahiro Kosuge, Tomoyuki Ohishi, Masamichi Nishihara, Atsushi Takahara, Hideyuki Otsuka

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86 Citations (Scopus)


Visualization and quantitative evaluation of covalent bond scission in polymeric materials are highly important for understanding failure, fatigue, and deterioration mechanisms and improving the lifetime, durability, toughness, and reliability of the materials. The diarylbibenzofuranone-based mechanophore radical system enabled, through electron paramagnetic resonance spectroscopy, in situ quantitative evaluation of scission of the mechanophores and estimation of mechanical energy induced along polymer chains by external forces. The coagulation of polymer solutions by freezing probably generated force but did not cleave the mechanophores. On the other hand, cross-linking led to efficient propagation of the force of more than 80 kJ?mol-1 to some mechanophores, resulting their cleavage and generation of colored stable radicals. This mechanoprobe concept has the potential to elucidate other debated issues in the polymer field as well.

Original languageEnglish
Pages (from-to)6168-6172
Number of pages5
JournalAngewandte Chemie - International Edition
Issue number21
Publication statusPublished - 2015 May 18
Externally publishedYes



  • cross-linked polymers
  • dynamic covalent chemistry
  • gels
  • mechanochemistry
  • mechanochromism

ASJC Scopus subject areas

  • Chemistry(all)
  • Catalysis

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