Synthesis and characterization of end‐group modified hyperbranched polyetherimides

End‐group modified hyperbranched polyetherimides were prepared by a one‐pot, two‐step reaction sequence. General synthetic techniques were developed to prepare both monofunctional terminating segments and the corresponding modified polyetherimide hyperbranched polymers. Monofunctional groups were used to terminate an AB 2 ‐type polycondensation reaction, generating capped hyperbranched polymers (HBPs). The composition and constitution of the end groups controlled the solubility and thermal properties of the HBPs. For the same polymer backbone, different end groups were able to shift the glass‐transition temperature nearly 100 °C. End‐group modification greatly influenced the film‐forming ability of the HBPs.