Synthesis of hyperbranched polyethers with diverse structures based on “A1 + B2” ring-opening polymerization

Abstract

The research on hyperbranched polyethers (HBPEths) currently focused on two main areas: (1) the development of a practical synthesis method and (2) the functionalization of HBPEths. “A₁ + B₂” ring-opening polymerization (“A₁ + B₂”-ROP) offers an efficient approach to access functional HBPEths with controllable structures. In the present study, a series of HBPEths were successfully prepared by employing “A₁ + B₂”-ROP, where the A₁ and B₂ represent a monofunctional primary alcohol and a biepoxy monomer, respectively. The obtained HBPEths possessed molar masses ranging from 2600 to 30000 g/mol. By employing functional A₁ primary alcohol initiators, it is possible to directly introduce a single type or a mixture of functionalities including fluoride, alkyne, alkene, azide, and furfuryl groups into the HBPEths terminal structures, while by adjusting various B₂ monomers with different linkage between both epoxy groups the main chain structures could be well controlled. Moreover, apart from conventional end group modification via esterification, the functionalities can be introduced during the one-pot “A₁ + B₂”-ROP process via ether bonds, which are stable against hydrolysis and redox-reaction.