The Role of Architecture in the Elastic Response of Semiflexible Polymer and Fiber Networks

摘要

We study the elasticity of cross-linked networks of thermally fluctuatingstiff polymers. As compared to their purely mechanical counterparts, it isshown that these thermal networks have a qualitatively different elasticresponse. By accounting for the entropic origin of the single-polymerelasticity, the networks acquire a strong susceptibility to polydispersity andstructural randomness that is completely absent in athermal models. Inextensive numerical studies we systematically vary the architecture of thenetworks and identify a wealth of phenomena that clearly show the strongdependence of the emergent macroscopic moduli on the underlying mesoscopicnetwork structure. In particular, we highlight the importance of the fullpolymer length that to a large extent controls the elastic response of thenetwork, surprisingly, even in parameter regions where it does not enter themacroscopic moduli explicitly. We provide theoretical scaling arguments torelate the observed macroscopic elasticity to the physical mechanisms on themicroscopic and the mesoscopic scale.