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Improved simulation method for the calculation of the intrinsic viscosity of some dendrimer molecules

Esteban Rodriguez·Juan J. Freire·G. del Rio Echenique·J. G. Hernandez Cifre·J. Garcia de la Torre
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Abstract

A method previously proposed for calculating the radius of gyration and the intrinsic viscosity of dendrimers is modified to give a more accurate description of existing experimental data. The new method includes some features that were not previously considered, namely: a) a correction term to take into account the contribution of individual friction beads, whose volumes are not negligible in comparison with the molecule size, b) a realistic distribution of internal angles between successive beads that define branching points in the molecule, c) a distribution of distances between branching points computed from Molecular Dynamics simulations of a small dendrimer with explicit solvent. Modification a) alone is able to give a good description of the experimental results obtained for polypropylene-imide with a diaminobutane core in water, while the simultaneous use of the three modifications is needed to adequately describe the experimental data of monodendrons and tridendrons of polybenzylether in THF.

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Esteban Rodriguez, Juan J. Freire, G. del Rio Echenique, J. G. Hernandez Cifre, J. Garcia de la Torre. 2006-11-03. Improved simulation method for the calculation of the intrinsic viscosity of some dendrimer molecules. https://arxiv.org/abs/cond-mat/0611090

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