Spontaneous and specific activation of chemical bonds in macromolecular fluids

TitleSpontaneous and specific activation of chemical bonds in macromolecular fluids
Publication TypeJournal Article
Year of Publication2010
AuthorsI Park, D Shirvanyants, A Nese, K Matyjaszewski, M Rubinstein, and SS Sheiko
JournalJournal of the American Chemical Society
Pagination12487 - 12491
Date Published01/2010

Mechanical activation of chemical bonds typically involves the application of external forces, which implies a broad distribution of bond tensions. We demonstrate that controlling the flow profile of a macromolecular fluid generates and delineates mechanical force concentration, enabling a hierarchical activation of chemical bonds on different length scales from the macroscopic to the molecular. Bond tension is spontaneously generated within brushlike macromolecules as they spread on a solid substrate. The molecular architecture creates an uneven distribution of tension in the covalent bonds, leading to spatially controlled bond scission. By controlling the flow rate and the gradient of the film pressure, one can sever the flowing macromolecules with high precision. Specific chemical bonds are activated within distinct macromolecules located in a defined area of a thin film. Furthermore, the flow-controlled loading rate enables quantitative analysis of the bond activation parameters.

Short TitleJournal of the American Chemical Society