Synthesis and characterisation of amphiphilic, metal-containing block copolymers via anionic polymerization

Ferrocene-containing BCPs exhibit high thermal and chemical stability, along with useful electrical properties, making them suitable for applications ranging from ceramic precursors to biomedical and sensing materials. Although ferrocene polymers were first reported in 1955, significant progress occurred in 1992 with the discovery of 1,1′-dimethylsilaferrocenophane, enabling ring-opening polymerisation and access to well-defined, high-molar-mass polymers. Since then, polydimethylsilaferrocenophane (PFS)-based BCPs have attracted considerable interest due to their etch resistance, catalytic and redox activity, and ability to form magnetic ceramic nanodomains. Polylactic acid (PLA) is synthesised via two distinct pathways: the condensation polymerisation of lactic acid or the pseudo-anionic ring-opening polymerisation of the cyclic lactide under tin(II) catalysis. The resulting polymer has numerous applications including use as filament for 3D printing, coating, wires or packaging films. The wide range of applications of PLA, in conjunction with its reliance on renewable resources for monomer production, positions it as a pivotal element in the shaping of a greener future. This study presents the synthetic route to well-defined PFS-b-PLA BCPs. End-functionalisation of PFS was achieved through the end capping of active carbanionic PFS chains with benzyl glycidyl ether (BGE). The monohydroxyl-functionalised PFS obtained is used as a macro-initiator for the catalytic ROP of L-lactide. This route offers a convenient way to fabricate nanoporous materials by using the capability of selective degradation of the PLA block segment. These materials have a variety of applications across different fields, ranging from adsorption and filtration processes to more specific capture and release processes. A range of BCPs were synthesised and characterised by ¹H NMR spectroscopy, size exclusion chromatography (SEC), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Furthermore, self-assembly behaviour of the polymers and selective degradation of PLA were investigated. To characterise the resulting morphology, ultrathin films were prepared and transmission electron microscopy (TEM) was performed.