6533b836fe1ef96bd12a1283

RESEARCH PRODUCT

Effect of Chain Stiffness on the Adsorption Transition of Polymers

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Polymers grafted with one chain end to an impenetrable flat hard wall which attracts the monomers with a short-range adsorption potential (of strength e) are studied by large scale Monte Carlo simulations, using the pruned–enriched Rosenbluth method (PERM). Chain lengths up to N = 25600 steps are considered, and the intrinsic flexibility of the chain is varied via an energy penalty for nonzero bond angles, eb. Choosing qb = exp(−eb/kBT) in the range from qb = 1 (fully flexible chains) to qb = 0.005 (rather stiff chains with a persistence length of about lp=52 lattice spacings), the adsorption transition is found to vary from about e/kBTc ≈ 0.286 to e/kBTc ≈ 0.011, confirming the theoretical expectation that e/kBTc∝1/lp for large lp. The simulation data are compatible with a continuous adsorption transition for all finite values of lp, while in the rigid rod limit (lp→∞) a first order transition seems to emerge. Scaling predictions and blob concepts on the structure of weakly adsorbed semiflexible polymers...