A new class of inherently adaptive polymer nanocomposites is developed where stress-enabled redox reactions are used in the context of a solid polymer electrolyte to form deposits which render mechanical strengthening effects. Experimental investigations were conducted to provide insight into this self-adaptation phenomenon. Results of tests conducted on bolted composite joints demonstrated the occurrence of this self-adaptation phenomenon. Experiments were also performed on cracked composite specimens where the potential of the self-adaptation phenomenon to repair cracks was demonstrated. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40620.