Copper-mediated stepwise polymerization of benzynes: construction of amphiphilic block copolymers and their self-assembly in water

Abstract

A novel synthetic approach for preparing well-defined amphiphilic poly(ortho-phenylene) (PoP) block copolymers via direct polymerization of benzynes has been reported. The polymerization of benzynes generated from o-trimethylsilyl aryl triflates with single hexyl or oligoethylene oxide side chains proceeded smoothly in the presence of copper(I) cyanide at room temperature, yielding PoP homopolymers with narrow molecular weight distributions. Block copolymers were prepared by the stepwise polymerization of two different benzynes, where the second benzyne was polymerized at the end of the PoP derived from the first benzyne. Spherical assemblies with diameters of 80–100 nm were formed from an amphiphilic block copolymer with a linear arrangement of hydrophobic and hydrophilic blocks in water. This synthetic approach opens new possibilities for various applications by enabling the design of well-defined PoP-based block copolymers.