title: Computational design of active, self-reinforcing gels.
abstract: Many living organisms have evolved a protective mechanism that allows them to reversibly alter their stiffness in response to mechanical contact. Using theoretical modeling, we design a mechanoresponsive polymer gel that exhibits a similar self-reinforcing behavior. We focus on cross-linked gels that contain Ru(terpy)(2) units, where both terpyridine ligands are grafted to the chains. The Ru(terpy)(2) complex forms additional, chemoresponsive cross-links that break and re-form in response to a repeated oxidation and reduction of the Ru. In our model, the periodic redox variations of the anchored metal ion are generated by the Belousov-Zhabotinsky (BZ) reaction. Our computer simulations reveal that compression of the BZ gel leads to a stiffening of the sample due to an increase in the cross-link density. These findings provide guidelines for designing biomimetic, active coatings that send out a signal when the system is impacted and use this signaling process to initiate the self-protecting behavior.
authors.affiliation: Chemical Engineering Department, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, USA.
authors.forename: Victor V
authors.initials: VV
authors.lastname: Yashin
authors.forename: Olga
authors.initials: O
authors.lastname: Kuksenok
authors.forename: Anna C
authors.initials: AC
authors.lastname: Balazs
mesh_terms: D005782:Gels / Q000737:chemistry*; D007700:Kinetics; D008024:Ligands; D008956:Models, Chemical; D008958:Models, Molecular; D010084:Oxidation-Reduction; D011725:Pyridines / Q000737:chemistry; D012428:Ruthenium / Q000737:chemistry
chemical_list: C517923:(2,2'-6',2'')-terpyridine; D005782:Gels; D008024:Ligands; D011725:Pyridines; D012428:Ruthenium