Mechanochromic Self-Healing Materials with Good Stretchability, Shape Memory Behavior, Cyclability, and Reversibility Based on Multiple Hydrogen Bonds.

It is challenging to develop materials with room-temperature self-healing ability and mechanochromic response from mechanical stimuli to optical signals by a facile and simple preparation process. Herein, novel mechanochromic self-healing materials were designed by a simple synthesis procedure, balancing the mechanical properties, self-healing, stretchability, and mechanochromic response. Moreover, we designed and prepared the mechanochromic self-healing materials with different soft and hard segments by introducing multiple hydrogen bonds into the network, improving the mechanical properties and self-healing efficiency. In addition, the optimized sample exhibited good shape memory behavior (shape recovery ratio of 94.4%), self-healing properties (healed by pressing during stretching process), high tensile strength (17.6 MPa), superior stretchability (893%), fast mechanochromic response (strain of 272%), and great cyclic stretching-relaxing properties (higher than 10 times at strain of 300%). Above all, mechanochromic self-healing materials have promising potential in various fields, such as stress sensing, inkless writing, damage warning, deformation detection, and damage distribution.