Impact of Core Architecture on Solution Properties of Dendrimer-like Star Copolymers

We present a small-angle neutron scattering study of a series of isomeric dendrimer-like star copolymers investigated in solution. Each copolymer consists of a highly branched core with linear partially deuterated polymer chains emanating from the outermost generation to create a starlike copolymer. By studying the copolymers in solvents contrast matched to the outer starlike chains, we focus our study on the effects of the core branching architecture. In our dilute solution data analysis we use models to obtain analytical expressions for the form factor of the copolymer cores. We find the core radius of gyration and fractal dimension depend on the core branching architecture. From our semidilute data we obtain experimental structure factors and see evidence of liquidlike structuring in some copolymers. Thus, the architectural features of these isomeric copolymers have an impact on both the conformation of and interactions between these molecules in solution.