Mechanochromic hydrogel fibers with multiple fluorescent colors.

Mechanochromic polymers can change their color in reimsponse to external force and have shown promising applications in stress sensing and failure warning. They are usually obtained as thin film or bulky specimen. The mechanochromic fibers, which could be used to make smart fabrics, have been seldom reported due to the lack of efficient fabrication techniques. In this work, we report a general method using photo-polymerization of microgel solution in a template tube to produce mechanochromic hydrogel fibers. The obtained hydrogel fibers can generate visible and fluorescent color change upon deformation. The diameter of the mechanochromic fibers could be easily adjusted by using different template tubes. The mechanochromic fibers could be fabricated as long as 1 meter. With reducing the fiber diameter or increasing the microgel concentration, the mechanical properties of the mechanochromic fibers could be improved, leading to more obvious mechanochromic behavior. We further use the polymethacrylate to coat the hydrogel fibers, to prevent the loss of water in the fibers and increase the storage time. The mechanochromic fibers with multiple fluorescent colors are further fabricated by utilizing different microgel solution. Our work provides an easy and effective method to fabricate mechanochromic fibers with different color change ability. This article is protected by copyright. All rights reserved.