Molecular dynamics simulations of polyelectrolyte brushes [Elektronische Ressource] / von Arun Kumar N.

Molecular Dynamics Simulationsof Polyelectrolyte BrushesDissertationzur Erlangung des akademischen GradesDoktor der Naturwissenschaften (Dr. rer. nat.)in der Wissenschaftsdisziplin Theoretische Physikeingereicht an derMathematisch{Naturwissenschaftlichen Fakult at der Universit at Potsdamangefertigt amMax{Planck{Institut fur Kolloid- und Grenz achenforschung in GolmvonArun Kumar N.geboren am 7. Juni 1979 in Kottayam, IndienPotsdam, im Januar 2006AbstractThis thesis studies strong, completely charged polyelectrolyte brushes. Extensive moleculardynamics simulations are performed on di eren t poly brush systems using localcompute servers and massively parallel supercomputers. The full Coulomb interaction ofcharged monomers, counterions, and salt ions is treated explicitly. The polymer chains areanchored by one of their ends to a uncharged planar surface. The chains are treated under goodsolvent conditions. Monovalent salt ions (1:1 type) are modelled same as counterions. Thestudies concentrate on three di eren t brush systems at constant temperature and moderateCoulomb interaction strength (Bjerrum length equal to bond length):The rst system consists of a single polyelectrolyte brush anchored with varying graftingdensity to a plane. Results show that chains are extended up to about 2=3 of their contourlength. The brush thickness slightly grows with increasing anchoring density.