Confined polymer chains in poor solvent

The conformation of polymer chains in a poor solvent and confined in a slit of width D is studied. A variational theory is used to calculate the mean square end-to-end distance, For the asymptotic values of D, the results coincide with the prediction of the scaling theory. For small values of D; the polymer has a two-dimensional (d = 2) behavior, while for large values of D the polymer behaves as a three-dimensional (d = 3) system. The cross-over between these two regimes occurs monotonically. The effect of the interaction strength between the polymer and the plates is assumed to be repulsive (C-0 > 0) and shown to be less important than the effect of collapse forces between monomers. (C) 1999 Elsevier Science Ltd. All rights reserved.