Computer simulation of dendrimers and hyperbranched polymers

Highly branched molecules such as dendrimers possess fully branched, focal-cored tree-like structures whereas their hyperbranched cousins contain a mixture of branched and unbranched sites and hence typically do not have a symmetric topology. Experiment and simulation have revealed these materials can exhibit an intrinsic shear viscosity that peaks with molecular weight rather than one that constantly increases with molecular weight as illustrated by linear chains. Applications in supramolecular chemistry, drug delivery and other guest-host applications bave motivated further interest in these molecules in terrns of their size, shape and interior density profiles. This talk will summarise an ongoing computational investigation into dendrimers and hyperbranched polymers under shear and elongational flow. The technique employed is Brownian dynamics in the presence of excluded volume and hydrodynamic interactions. The behaviour of various statistical and rheological quantities will be presented including their dependence on the extent and the distribution of branched sites within the dendritic molecule.