화학공학소재연구정보센터
Macromolecules, Vol.31, No.7, 2343-2348, 1998
Dimensional and hydrodynamic factors for flexible star polymers in the good solvent limit
Star chains composed of arms with uniform length were generated on a simple cubic lattice by the Monte Carlo method using the enrichment algorithm, which enabled us to obtain chains with total segment numbers (N) up to 1200. The number of arms (f) ranged from 2 to 24. The radius of gyration ([S-2](1/2)), the dimensionless intrinsic viscosity (E), and the hydrodynamic radius (R-H) were evaluated as functions off and N by averaging over more than 4000 samples. The calculations of E and R-H were made according to Zimm's method. It was found that the radius expansion factor (alpha(s)) for Star chains with long arms obeys the relation alpha(s)(2) = 1.53z(2/5), which is known for long flexible linear chains, where z is the excluded volume parameter. The ratios of [S-2], E, and R-H Of star chains to those for Linear chains were evaluated as functions off. These ratios obtained and the Flory factors for the intrinsic viscosity and R-H extrapolated to N-1/2 --> 0 reproduced experimental data well.