CO2‐Breathing Induced Reversible Activation of Mechanophore within Microgels

In this work, CO₂‐breathing induced reversible activation of mechanophore within microgels is reported. The microgels are prepared through soap‐free emulsion polymerization of CO₂‐switchable monomer 2‐(diethylamino)ethyl‐methacrylate, using spiropyran (SP) based mechanophore MA‐SP‐MA as cross‐linker. The microgels can be swollen by CO₂ aeration. The swelling of microgels activates the SP mechanophore into merocyanine, causing distinguished color and fluorescence change. Moreover, these transitions are highly reversible, and the initial states of microgels can be easily recovered by “washing off” CO₂ with N₂. The present contribution represents the first example of CO₂‐breathing activation of mechanophore within microgels.