Compression of Bottle-Brush Layers Andrey Dobrynin, University of Connecticut, DMR 1004576

1. Compression of Bottle-Brush LayersAndrey Dobrynin, University of Connecticut, DMR 1004576 Friction and lubrication is a part of our everyday experience ranging from machinery to biological organisms. Many connective tissues, such as cartilage, demonstrate excellent lubrication and wear characteristics. The surface of the cartilage is covered with the brush-like polyelectrolyte layer. This brush layer, which faces a similar layer on the opposing cartilage, is sheared as two surfaces slide passing each other during the joint motion (see Figure). Using molecular dynamics simulations and theoretical analysis we have established for the first time that bottle-brush macromolecules behave as semiflexible chains with effective bending rigidity determined by the length of the side chains. This leads to a very strong dependence of the disjoining pressure on substrate separation. Dependence of the Disjoining Pressure on Substrate Separation

2. Compression of Bottle-Brush LayersAndrey Dobrynin, University of Connecticut, DMR 1004576 Broader Impact Daniel Russano was awarded 2011 KatzensteinPrize (UConn) for outstanding undergraduate research in physics for research paper “Interaction between Brush Layers of Bottle-Brush Polyelectrolytes. Molecular Dynamics Simulations.” This research was done under supervision of Prof. Andrey Dobrynin at the Institute of Materials Science, University of Connecticut.