Synthesis and Bulk Self-Assembly of ABC Star Terpolymers with a Polyferrocenylsilane Metalloblock

The synthesis, characterization, and self-assembly of a range of ABC star polymers with arms of polyisoprene, poly(ferrocenylethylmethylsilane), and polystyrene is reported. A library of azide-functionalized polyisoprene and poly(ferrocenylethylmethylsilane) homopolymers were prepared by living anionic polymerization. Polystyrene was synthesized by living anionic polymerization and quenched with 3-triisopropylsilylethynyl-5-trimethylsilylethynylbenzaldehyde, yielding "core-functionalized" polystyrene with two different alkyne units. The azide-functionalized monomers were sequentially attached to core-functionalized polystyrene via copper(I)-catalyzed azide-alkyne cycloaddition reactions, giving polystyrene-polyisoprene-poly(ferrocenylethylmethylsilane) ABC star terpolymers with different compositions and narrow dispersities. Additionally, a chlorosilane route was employed as an alternative means of synthesis. Bulk films of each star terpolymer were prepared, and their self-assembly was analyzed by transmission electron microscopy. The formation of a diverse range of morphologies was observed, including lamellae with alternating cylinders and two different Archimedean tiling patterns.