Synthesis and direct assembly of linear–dendritic copolymers via CuAAC click polymerization-induced self-assembly (CPISA)

Abstract

A one-pot method was developed for the preparation of a linear–dendritic copolymer and its assemblies via copper-catalyzed azide–alkyne cycloaddition (CuAAC) click polymerization-induced self-assembly (CPISA). By utilizing a tris-triazoleamine-functionalized poly(ethylene glycol) (PEG) chain as a linear macroinitiator and a trifunctional AB₂ with one alkynyl group and two azido groups as a monomer, we successfully conducted CuAAC polymerization in methanol, water, or a methanol/water mixture with a solid content of 15 wt%. All polymerizations reached high monomer conversion and the rate of polymerization was readily tailored by the fraction of water in the solvent. The polymerization of the AB₂ monomer from the PEG macroinitiator produced solvent-insoluble dendritic blocks that assembled under polymerization conditions to form spherical micelles and large compound micelles, characterized by dynamic light scattering and transmission electron microscopy. This strategy broadens the topological architecture of copolymers synthesized by the PISA process and puts forward a new methodology for direct preparation of nanostructures based on linear–dendritic polymers.