6533b7d4fe1ef96bd1261d56

RESEARCH PRODUCT

Can one detach a fully adsorbed flexible polymer chain by an ultra-small external force?

Alexey A. PolotskyKurt BinderLeonid I. KlushinAlexander M. Skvortsov

subject

chemistry.chemical_classificationRange (particle radiation)Materials scienceOrders of magnitude (temperature)General Physics and AstronomyBrushNanotechnologyInteraction energyPolymerlaw.inventionAdsorptionchemistryChemical physicslawSoft matterMacromolecule

description

Full adsorption of flexible chains onto typical solid substrates occurs at a surface interaction energy of (5–10) kBT. The corresponding detachment force is in the range 10–50 pN. In contrast to “bare” solid substrates common to non-living materials, surfaces coated with brush-like polymer layers are very common in biological soft matter. We employ a simple mean-field approach to describe the effects of weak attraction between a floating long macromolecule and the brush. We show that even for a moderately thick brush a very small effective attraction is enough to produce complete binding of the long chain. The detachment force scales as , where W is the brush thickness. Hence the force could be 1 to 2 orders of magnitude smaller than in the case of typical solid substrates.

https://doi.org/10.1209/0295-5075/104/18003