Imaging and measuring compression stresses secure a safe and healthy life. Compression stresses in kPa range are not easily detected by conventional mechanoresponsive materials because microscopic molecular motion of the chromophores is not induced by such weak stresses. Moreover, imaging of the stress distribution is not achieved so far. The present study shows a sponge device combining two stimuli‐responsive materials, a capsule releasing interior liquid and color‐changing polymer in responses to compression stress and chemical stimulus, respectively. The stimuli‐responsive capsule is dispersed on a melamine sponge comprised of the fibers with coating the layered polydiacetylene (PDA). The application of weak compression stresses induces collapse of the capsules, outflow of the interior liquid, and subsequent irreversible color change of PDA. The cascading response in the sponge device colorimetrically enables imaging of the distribution and measuring the strength of the compression stresses in kPa range. Furthermore, the device demonstrates imaging and measuring unknown weak compression stresses applied by the irregular‐shaped objects. A couple of clinical issues in surgical operation of intestine are studied using the stress‐imaging sponge device. The device and its design strategy can be applied to stress imaging in a variety of fields.

Stimuli‐Responsive Sponges In article number 2206097 , Nahoko Ono, Syuji Fujii, Yuya Oaki, and co‐workers show stress‐imaging sponge device combining stimuli‐responsive conjugated polymer and capsule materials. The sponge device visualizes and quantifies the local compression stress and its distribution applies by irregularly shaped objects. The stress distribution caused by surgical device is visualized to solve a couple of clinical issues.

No abstract

No abstract

No abstract