Constructive adaptation of synthetic polymers in response to typically destructive environmental stressors

Although engineering and biological systems are surrounded by similar destructive environmental stressors, such as loads, sunlight, water, and greenhouse gases, their responses are typically different. The biological systems exhibit extraordinary adaptive capacity by turning destructive environmental stressors into constructive factors. For example, bone and muscle turn the typically destructive mechanical loads into constructive factors to build mass and mechanical strength. Plants harness sunlight and carbon dioxide, which otherwise degrades substance, to constructively synthesize polysaccharides and grow stiffness and strength. The engineering systems, on the contrary, typically do not possess the intelligence of constructive adaptation but weaken in response to environmental stressors. Take synthetic polymers as an example, they typically fatigue, age, and degrade with weakening mechanical properties during exposure to environmental stressors, such as loads, sunlight, water, and greenhouse gases. Here, we will present our recent efforts in designing synthetic polymer networks capable of turning destructive environmental stressors into constructive factors for strengthening their bulk and interfacial mechanical properties. Our efforts may open the door for the design of synthetic engineering materials to imitate the constructive adaptation of the biological systems in response to environmental stressors, for applications such as artificial muscles, soft robotics, and flexible electronics.