Polyphosphinoborane Block Copolymer Synthesis Using Catalytic Reversible Chain‐Transfer Dehydropolymerization

Abstract

An amphiphilic block copolymer of polyphosphinoborane has been prepared by a mechanism-led strategy of the sequential catalytic dehydropolymerization of precursor monomers, H 3 B • PRH 2 (R = Ph, nhexyl), using the simple pre-catalyst [Rh-(Ph 2 PCH 2 CH 2 PPh 2 ) 2 ]Cl. Speciation, mechanism and polymer chain growth studies support a step-growth process where reversible chain transfer occurs, i.e. H 3 B • PRH 2 / oligomer/polymer can all coordinate with, and be activated by, the catalyst. Block copolymer [H 2 BPPhH] 110 -b-[H 2 BP(n-hexyl)H] 11 can be synthesized and self-assembles in solution to form either rod-like micelles or vesicles depending on solvent polarity.