Photoinduced Mechanical Cloaking of Diarylethene‐Crosslinked Microgels

Abstract

AbstractThe serial connection of multiple stimuli‐responses in polymer architectures enables the logically conjunctive gating of functional material processes on demand. Here, a photoswitchable diarylethene (DAE) acts as a crosslinker in poly(N‐vinylcaprolactam) microgels and allows the light‐induced shift of the volume phase‐transition temperature (VPTT). While swollen microgels below the VPTT are susceptible to force and undergo breakage–aggregation processes, collapsed microgels above the VPTT stay intact in mechanical fields induced by ultrasonication. Within a VPTT shift regime, photoswitching of the DAE transfers microgels from the swollen to the collapsed state and thereby gates their response to force as demonstrated by the light‐gated activation of an embedded fluorogenic mechanophore. This photoinduced mechanical cloaking system operates on the polymer topology level and is thereby principally universally applicable.