Models of Autonomic Self-Healing of Reversible Networks

University Of North Carolina At Chapel Hill, Chapel Hill NC

Investigators

Abstract

Michael Rubinstein of the University of North Carolina, Chapel Hill, is supported by an award from the Theoretical and Computational Chemistry program to develop a theory of the self-healing process for the major class of autonomic self-healing polymeric material: networks with reversible associations and dissociations. The self-healing ability of these polymers originates in high non-equilibrium concentration of dissociated groups created at the fractured surfaces that decays very slowly during a "waiting" time while two broken parts of the material are kept separated from each other. One of the objectives of the project is to determine which molecular parameters, such as degree of polymerization, number of associating groups per chain, and the strength of associations maintain the high excess of dissociated groups at the fractured surfaces for the longest period of waiting time. The research contributes to the development of synthetic self-healing materials which are expected to have major technological impact by extending the working life and safety of polymeric components used in a broad range of applications. Results of this research are incorporated into new problem sets and supplementary materials for the "Polymer Physics" textbook by M. Rubinstein and R. H. Colby. Examples of self-healing materials are being used in the design of the updated "Zoom In" exhibit at the Morehead Planetarium and Science Center as well as in lectures by the PI to high school students at the "Science Spectrum" and "Science at the Edge" series at UNC.