Sphere-Like Fourth Generation Pseudo-Dendrimers with a Hyperbranched Core

A pseudo-dendritic structure clear of linear units is obtained from a hyperbranched aliphaticaromatic polyester core modified by a B-protected AB2 monomer. The chosen sequence of reaction and deprotection steps yields four generations of pseudo-dendrimers with either silyl- or OH-terminal units. 1H and 13C NMR confirm the extent of modification and the degree of branching in the different generations. The influence of generation number, end group type, and degree of branching on the specific solution behavior of the pseudo-dendrimers is investigated by size-exclusion chromatography coupled to static light scattering and by intrinsic viscosity characterization. Apparent density and scaling parameters indicate increased compactness of the pseudo-dendrimers with increasing generation number.