Hyperbranched aryl polycarbonates derived from A2B monomers versus AB2 monomers Academic Article uri icon

abstract

  • Hyperbranched aryl polycarbonates were prepared via the polymerizations of A2B and AB2 monomers, which involved the condensation of chloroformate (A) functionalities with tert-butyldimethylsilyl-protected phenols (B), facilitated by reactions with silver fluoride. The polymerization of the A2B monomer gave hyperbranched polycarbonates bearing fluoroformate chain ends, which were hydrolyzed to phenolic chain-end moieties and further elaborated to tert-butyldimethylsilyl ether groups. The polymerization of the AB2 monomer gave tert-butyldimethylsilyl ether-terminated hyperbranched polycarbonates. The polymerizations were conducted at 23-70 °C in 20% acetonitrile/tetrahydrofuran in the presence of a stoichiometric excess of silver fluoride for 20-40 h to afford hyperbranched polycarbonates with weight-average molecular weights exceeding 100,000 Da and polydispersity indices of typically 2-3. The degrees of branching were determined by a reductive degradation procedure followed by high-performance liquid chromatography. Alternatively, the degrees of branching were measurable by solution-state 1H NMR analyses and agreed with the statistical 50% branching expected for the polymerization of A2B and AB2 monomers not experiencing constructive or destructive electronic effects on the reactivity of the multiple functional groups. © 2002 Wiley Periodicals, Inc. J. Polym. Sci. Part A: Polym. Chem.

author list (cited authors)

  • Bolton, D. H., & Wooley, K. L.

citation count

  • 41

publication date

  • February 2002

publisher