Self-Assembly of a Novel Organometallic−Inorganic Block Copolymer in Solution and the Solid State:  Nonintrusive Observation of Novel Wormlike Poly(ferrocenyldimethylsilane)-b-Poly(dimethylsiloxane) Micelles

Abstract

The novel organometallic−inorganic diblock copolymer, poly(ferrocenyldimethylsilane)-b-poly(dimethylsiloxane) (PFS-b-PDMS) (block ratio = 1.0:6.0) (M n = 35 100 g/mol with a narrow molecular weight distribution M w/M n = 1.10 based upon gel permeation chromatography in THF using polystyrene standards) forms long rodlike micelles in hexane solution. After the solvent was evaporated, transmission electron microscopy (TEM) and atomic force microscopy (AFM) showed that individual cylindrical micellar structures form with the iron-rich, organometallic PFS core encased in a sheath (corona) of PDMS. The block copolymer forms hexagonally packed cylinders in the bulk, and exposure to warm hexane causes the cylinders to disperse in the solvent. Both static and dynamic light scattering (SLS and DLS) were used to establish that the micelles are flexible rods which are stable in hexane even at 80 °C. The as-prepared sample possessed an aggregation number of ca. 2000 polymer molecules. Ultrasonication (60 W) in hexane led to the generation of short cylinders with an aggregation number of ca. 700. Since PFS can be oxidized to a semiconductive state and PDMS is an insulator, these rodlike micellar structures have the potential to function as nanoscale self-insulated wires.

Synthesis and Solution Self‐Assembly of Polyisoprene‐block‐poly(ferrocenylmethylsilane): A Diblock Copolymer with an Atactic but Semicrystalline Core‐Forming Metalloblock

“…325 This was also detected for PI-b-PFDMS cylindrical micelles. Significantly, it was found that addition of further unimer to these short micelles resulted in longer cylinders, with the preformed micelles essentially acting as "seeds" for further unimer nucleation.…”

“…R = R' = Me, PFDMS; R = R' = Et, PFDES) and is able to crystallise can self-assemble in various solvents to produce a number of different micellar morphologies including cylinders, 254,255,325 tubes, [326][327][328] fibres, 329 platelets 220 and, if the core-forming block does not crystallise, usually spheres. 47,225,330 As an example, when a sample of PFDMS50-b-PDMS300, with a block ratio of 1:6, was heated and cooled in a selective solvent for the PDMS block such as n-hexane, cylindrical micelles were obtained composed of a PFDMS core and a PDMS corona.…”

Synthesis of Glycidyl Ether of Poly(bisphenol-A 1,1′-ferrocene dicarboxylate) and Its Electrochemical Behavior

“…It appears that the increase of scan rate can promote the electron exchange at the electrode surface; however, it make the electrolyte diffusion in the film more difficult because the electrolyte did not have enough time to diffuse at the high scan rate. 4 ] as electrolyte. It can be seen that the peak currents of GEPBFC in THF are higher than that in CH 2 Cl 2 .…”

“…Ferrocene-based polymers have attracted increasing research interest for their unique electronic, electrochemical, magnetic and catalytic properties [1][2][3][4]. They have been applied in many fields such as electrode modifications [5,6], molecular devices [7,8], electrochemical sensors [9][10][11] and burn-rate catalysts [12].…”

Polymer science with transition metals and main group elements: Towards functional, supramolecular inorganic polymeric materials

“…However, using crystallizable PFS blocks, we found that well-defined cylindrical micellar structures could be generated. For example, the solution aggregation of PFS-b-PDMS block copolymers (14) with a poly(ferrocenyldimethylsilane) block in n-hexane as a PDMS-selective solvent yielded novel wormlike micelles (1 : 6 PFS : PDMS) 48 or semihollow nanotubes (1 : 13 PFS : PDMS) 49 with a PFS core and a PDMS corona. These structures maintain their integrity in the solid state, and the iron-rich cores can be readily visualized by transmission electron microscopy (TEM); staining is unnecessary because of the intrinsic electron density contrast provided by the presence of the iron-containing PFS block.…”