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.