Title: STAR POLYMERS IN GOOD SOLVENTS FROM DILUTE TO CONCENTRATED REGIMES: CROSSOVER APPROACH
Author(s): L.Lue (Department of Chemical Engineering, UMIST, Manchester M60 1QD, United Kingdom), S.B.Kiselev (Chemical Engineering Department, Colorado School of Mines, 1500 Illinois St., Golden, CO 80401--1887, USA)

An introduction is given to the crossover theory of the conformational and thermodynamic properties of star polymers in good solvents. The crossover theory is tested against Monte Carlo simulation data for the structure and thermodynamics of model star polymers. In good solvent conditions, star polymers approach a ``universal'' limit as $N\to\infty$; however, there are two types of approach towards this limit. In the dilute regime, a critical degree of polymerization $N^*$ is found to play a similar role as the Ginzburg number in the crossover theory for critical phenomena in simple fluids. A rescaled penetration function is found to control the free energy of star polymer solutions in the dilute and semidilute regions. This equation of state captures the scaling behaviour of polymer solutions in the dilute/semidilute regimes and also performs well in the concentrated regimes, where the details of the monomer-monomer interactions become important.

Key words: star polymer, computer simulation, renormalization group, polymer field theory
PACS: 61.25.Hq