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Download or read book Molecular Dynamics Simulation and Modelling of Polymer-nanoparticle Associations written by Jean-Christophe Goulet and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "Polymer-nanoparticle composites exhibit exceptional mechanical properties and are used for a wide range of applications. It is known that the macroscopic properties of these materials depend strongly on the microscopic polymer structure and conformation. However, the fundamental interactions between chains and nanoparticles (NP) are still poorly understood.In this thesis, the polymer-nanoparticle interaction, in the single-polymer-chain-nanoparticle limit is studied using molecular dynamics (MD) simulations. Textbook results for freely-jointed-chains and excluded-volume chains (namely, the scaling for the end-to-end vector and radius of gyration, the end-to-end fluctuations and the force-extension relationship) are used to assess simulation accuracy (e.g., often showing that long simulation times are required to generate equilibrium theoretical properties). Next, a polymer chain adsorbed on a spherical NP is studied. The system in a force-free state is modelled as a Gaussian, furnishing the probability distribution function of the chain end-to-end vector, and the chain tension and free energy. Chain desorption is investigated, furnishing a force-extension relationship, which is broken down into four regimes each controlled by different dynamics. A model accounting for three of the four regimes is presented. Finally, NP diffusion in polymer solutions, networks and on a periodic chain is studied; this provides insights into the relationship between polymer-nanoparticle interactions and NP diffusion"--