Hyperbranched polyester based on the core + AB2 approach: Synthesis and structural investigation

In this study, structural buildup studies during the synthesis of fifth‐generation hyperbranched polyesters (HBPs) from 2‐bis(hydroxymethyl) propionic acid (AB2) and glycerol (core) by a one‐pot process were undertaken. The variations in the degree of polymerization, hydrogen bonding, rheology, and role of cyclization were studied by NMR, Fourier transform infrared spectroscopy, rheometry, and matrix‐assisted laser desorption/ionization time of flight. The degree of branching was calculated at different time intervals from the integral peak areas of the terminal, linear, and dendritic repeating units of 1H‐NMR and 13C‐NMR. The rheology study performed on the HBPs revealed that hydrogen bonds played an important role in the determination of the melt viscosity.