초록 |
Mechanical force on a polymer can be translated into productive chemical responses using molecular force probes called mechanophores. Mechanophore-linked polymers have accomplished numerous functions including visualizing stress, self-strengthening, and releasing small molecules. To rationally utilize the mechanochemical reactions, the effect of molecular structure on mechanophore activity needs to be understood. Here, we focus on how molecular geometry influences mechanophore activation in bulk elastomers with color-changing mechanophores, spriopyran(SP) and naphthopyran(NP). Two mechanically active SPs and six NP regioisomers were synthesized. SP or NP incorporated specimens were tested to compare the mechanical reactivity under tension. Although the exact behavior of mechanophores in heterogenous polymer networks was difficult to interpret, the current work provides some guidelines for designing new mechanophores as well as controlling their activity. |