Using Branching and Endgroups to Control the Physical Properties of Macromolecules: Systematic Studies of Etherimide Polymers

Abstract

To survey the effect that end-group composition and constitution have on macromolecular physical properties, end-group modified hyperbranched polyetherimides were prepared by a one-pot, two-step reaction sequence. General synthetic techniques were developed to prepare both mono-functional terminating segments and the corresponding modified polyetherimide hyperbranched polymers. Mono-functional groups were used to terminate an AB2-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 also greatly influenced the film-forming ability of the HBPs.