Relaxation Dynamics of Semiflexible Fractal Macromolecules

Polymers (Basel). 2016 Jul 15;8(7):263. doi: 10.3390/polym8070263.

Abstract

We study the dynamics of semiflexible hyperbranched macromolecules having only dendritic units and no linear spacers, while the structure of these macromolecules is modeled through T-fractals. We construct a full set of eigenmodes of the dynamical matrix, which couples the set of Langevin equations. Based on the ensuing relaxation spectra, we analyze the mechanical relaxation moduli. The fractal character of the macromolecules reveals itself in the storage and loss moduli in the intermediate region of frequencies through scaling, whereas at higher frequencies, we observe the locally-dendritic structure that is more pronounced for higher stiffness.

Keywords: eigenmodes; fractals; hyperbranched polymers; mechanical relaxation; pseudo-dendrimers; semiflexibility.