A. Milchev et K. Binder, A POLYMER-CHAIN TRAPPED BETWEEN 2 PARALLEL REPULSIVE WALLS - A MONTE-CARLO TEST OF SCALING BEHAVIOR, EUROPEAN PHYSICAL JOURNAL B, 3(4), 1998, pp. 477-484
An off-lattice bead-spring model of a polymer chain trapped between tw
o parallel walls a distance D apart is studied by Monte-Carlo methods,
using chain lengths N in the range 32 less than or equal to N less th
an or equal to 512 and distances D from 4 to 32 (in units of the maxim
um spring extension). The scaling behavior of the coil linear dimensio
ns parallel to the plates and of the force on the walls is studied and
discussed with the help of current theoretical predictions. Also the
density profiles of the monomers across the slit are obtained and it i
s shown that the predicted variation with the distance z from a wall,
rho(z) proportional to z(1/nu), is obtained only when one introduces a
n extrapolation length lambda in the description, rho(z) proportional
to [(z + lambda)/D](1/nu), with lambda approximate to 0.35. An analogo
us result is also obtained for Gaussian chains (where 1/nu = 2).