Excluded volume effect in flexible dendrimer systems: A self-consistent field theory

We have studied the conformational and scaling behaviors of a flexible dendrimer immersed in athermal or good solvents. A self-consistent field theory combined with a pre-averaged excluded volume potential representing the two-body short-ranged interaction between the segments, was adopted to calculate the density profile of various generations and branch points thoroughly. Our calculation results support the "dense-core" model. We find the conformation of the dendrimer is strongly stretched in the dense central region, but much weakly stretched in the outer region where the segment density profile is shoulder shaped. Both our self-consistent field theory calculation and the Flory mean-field theory calculation give the same scaling law R proportional to (GP)^0.2N^0.4, where G is the generation number of the dendrimer, P is the spacer segment number, and N is the total segment number. If we fix G, the scaling law is simplified to R proportional to P^0.6 in good solvent.