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Hydrodynamic Shear Effects on Grafted and Non-Grafted Collapsed Polymers.

ABSTRACT: We study collapsed homo-polymeric molecules under linear shear flow conditions using hydrodynamic Brownian dynamics simulations. Tensile force profiles and the shear-rate-dependent globular-coil transition for grafted and non-grafted chains are investigated to shine light on the different unfolding mechanisms. The scaling of the critical shear rate, at which the globular-coil transition takes place, with the monomer number is inverse for the grafted and non-grafted scenarios. This implicates that for the grafted scenario, larger chains have a decreased critical shear rate, while for the non-grafted scenario higher shear rates are needed in order to unfold larger chains. Protrusions govern the unfolding transition of non-grafted polymers, while for grafted polymers, the maximal tension appears at the grafted end.

SUBMITTER: Schwarzl R

PROVIDER: S-EPMC6403890 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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Hydrodynamic Shear Effects on Grafted and Non-Grafted Collapsed Polymers.

Schwarzl Richard R Netz Roland R RR

Polymers 20180818 8

We study collapsed homo-polymeric molecules under linear shear flow conditions using hydrodynamic Brownian dynamics simulations. Tensile force profiles and the shear-rate-dependent globular-coil transition for grafted and non-grafted chains are investigated to shine light on the different unfolding mechanisms. The scaling of the critical shear rate, at which the globular-coil transition takes place, with the monomer number is inverse for the grafted and non-grafted scenarios. This implicates tha ...[more]

PMID: 30960851

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