Surface‐Initiated Anionic Polymerization of [1]Silaferrocenophanes for the Preparation of Colloidal Preceramic Materials

Abstract

A novel strategy for the preparation of poly(ferrocenylsilane) (PFS) immobilized on the surface of cross-linked polystyrene (PS) nanoparticles is reported. The ferrocene-containing core/shell architectures are shown to be excellent candidates as preceramic polymers yielding spherical ceramic materials consisting of iron silicide (Fe3 Si) and metallic iron after thermal treatment. For this purpose, dimethyl- and hydromethyl[1]silaferrocenophane monomers are polymerized by surface-initiated ring-opening polymerization upon taking advantage of residual vinylic moieties at the PS particle surface. A strategy for selective chain growth from the particle surface is developed without the formation of free PFS homopolymer in solution. The grafted particles are characterized using transmission electron microscopy (TEM) and dynamic light scattering (DLS). These particles are excellent precursors for ceramics as studied by thermogravimetric analysis (TGA). The composition of the ceramics is studied using X-ray diffraction (XRD) measurements, while the morphology is probed by scanning electron microscopy (SEM) revealing the original spherical shape of the precursor particles. Obtained ceramic materials- predominantly based on iron silicides-show ferromagnetic behavior as investigated by superconducting quantum interference device (SQUID) magnetization measurements at different temperatures.

Recent Trends in Metallopolymer Design: Redox‐Controlled Surfaces, Porous Membranes, and Switchable Optical Materials Using Ferrocene‐Containing Polymers

“…Elbert et al. investigated the living anionic ring‐opening polymerization of strained ansa ‐silaferrocenophane (FS) monomer by a grafting‐from polymerization strategy from the surface of silica nanoparticles . These PFS‐grafted particles were converted into magnetic Fe/Si/C ceramics.…”

“…investigated the living anionic ring-opening polymerization of strained ansa-silaferrocenophane (FS) monomer by ag rafting-from polymerization strategy from the surface of silica nanoparticles. [66] These PFS-grafted particles were converted into magnetic Fe/Si/Cc eramics. In ar ecent study,F cMA monomer was successfully polymerized by means of radical polymerization in emulsion leadingt om onodisperse metallopolymer-based and stimuli-responsive particles featuring a core-interlayer-shell (CIS) architecture for opticala pplications and the preparation of iron-based ceramics (cf.…”

Ceramic Nanocomposites from Tailor-Made Preceramic Polymers

“…The most prominent example in the field of ferrocene-containing polymers for the conversion into functional ceramic materials was reported by the group of Manners. By ring-opening polymerization (ROP) of ring-strained ansa -silaferrocenophanes, polyferrocenylsilanes (PFS) for the preparation of well-defined nanostructured ceramics could be obtained ( Figure 4 ) [ 116 , 117 , 118 ].…”

“…For instance, polyferrocenyldimethylsilane is a film-forming thermoplastic and can be melt-processed into various shapes such as nanofibers by electrospinning [ 119 ]. Thus, high-molecular weight polyferrocenylsilanes with linear, cyclic, or hyperbranched architecture and their block copolymers have shown potential in the preparation of shaped magnetic ceramics [ 120 , 121 , 122 , 123 , 124 , 125 ] and the self-assembly into well-defined hybrid architectures such as micelles [ 126 ], spheres [ 118 , 127 ], cylinders [ 128 ] and one-dimensional nanostructures [ 129 , 130 ]. Interestingly, PFS-derived ceramics possess tunable magnetic properties between the ferromagnetic and the superparamagnetic state, which can be achieved upon controlling the pyrolysis conditions of PFS.…”

Self‐Assembly and Surface Patterning of Polyferrocenylsilane‐Functionalized Gold Nanoparticles

“…We used poly(ferrocenyldimethylsilane) (PFDMS), a member of the polyferrocenylsilane family, a class of metallocene polymers known for its interesting redox, optical, preceramic, and other properties . These polymers have been used in sensing, as an electroactive component in photonic crystals, as ligands for the preparation of colloidal preceramic materials, and as an oxygen plasma‐resistant block in block copolymer‐based lithography . Thus, we aimed to exploit the electroactive properties of new PFDMS ligands for the SA and SP of NPs.…”