https://doi.org/10.1140/epje/i2009-10458-x
Regular Article
Molecular dynamics simulation of semiflexible polyampholyte brushes--The effect of charged monomers sequence
Institute for Advanced Studies in Basic Sciences (IASBS), P.O. Box 45195-1159, 45195, Zanjan, Iran
* e-mail: fazli@iasbs.ac.ir
Received:
21
January
2009
Revised:
15
March
2009
Accepted:
1
April
2009
Published online:
23
May
2009
Planar brushes formed by end-grafted semiflexible polyampholyte chains, each chain containing an equal number of positively and negatively charged monomers, are studied using molecular dynamics simulations. Keeping the length of the chains fixed, the dependences of the average brush thickness and equilibrium statistics of the brush conformations on the grafting density and the salt concentration are obtained with various sequences of charged monomers. When similarly charged monomers of the chains are arranged in longer blocks, the average brush thickness is smaller and the dependence of brush properties on the grafting density and the salt concentration is stronger. With such long blocks of similarly charged monomers, the anchored chains bond to each other in the vicinity of the grafting surface at low grafting densities and buckle toward the grafting surface at high grafting densities.
PACS: 82.35.Rs Polyelectrolytes – / 36.20.-r Macromolecules and polymer molecules – / 61.41.+e Polymers, elastomers, and plastics –
© EDP Sciences, SIF, Springer-Verlag Berlin Heidelberg, 2009