A series of poly(styrene‐block‐ferrocenyldimethylsilane) copolymers (SF) with different relative molar masses of the blocks were prepared by sequential anionic polymerization. The bulk morphology of these polymers, studied by TEM and SAXS, showed well‐ordered lamellar and cylindrical domains as well as disordered micellar structures. Temperature‐dependent rheological measurements exhibited an order–disorder transition for SF 17/8 (the numbers refer to the relative molar masses in 103 g/mol) between 170 and 180°C, and an order–order transition for SF 9/19 between 190 and 200°C. The morphologies of binary blends of the diblocks with homopolymer were also investigated. In the blends the molar mass of the homopolymer was always less than the molar mass of the matching block. Ordered spheres on a bcc lattice and double‐gyroid morphology were observed for the blends. The double‐gyroid morphology was found only in F‐rich diblock/homopolymer systems. © 1999 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 37: 1009–1021, 1999

We report on the fabrication and characterization of fully organometallic multilayer thin films, composed of poly(ferrocenylsilane) polyanions and polycations. These polyions were deposited electrostatically onto a variety of substrates including quartz, silicon, gold, and hydrophilic/hydrophobically patterned substrates, using layer-by-layer self-assembly. The deposition process was monitored by means of UV/visible absorption spectroscopy, showing a linear increase in absorption with the number of bilayers. Ellipsometry was used to measure the development of film thickness with the number of bilayers, revealing a linear relationship and a thickness contribution of approximately 0.4 nm/bilayer. The multilayer films were further characterized by X-ray photoelectron spectroscopy (XPS) and by cyclic voltammetry. By integration of the voltammetric signals, the surface concentration of the redox-active ferrocene units was obtained as a function of the number of poly(ferrocenylsilane) bilayers. Selective adsorption of the polyions was achieved onto the hydrophobic stripes of a pattern of CH3and OH-terminated alkanethiol monolayers on gold, forming patterned organometallic multilayer structures. This selective deposition was explained by taking hydrophobic and hydrogen-bonding interactions into account. The hydrophobic backbone of the poly-(ferrocenylsilane) polyions has favorable hydrophobic interactions with the methyl-terminated areas of the patterned substrate but not with hydroxyl-terminated domains, which are hydrogen-bonded with the solvent. The dipping sequence does not influence the selectivity of the multilayer deposition.

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A novel, anionic route to well-defined side-chain liquid-crystalline polysiloxanes is described. The usual cationic approach to these polymers leads to polydisperse materials with uncontrolled microstructures. Ring-opening polymerization of pentamethylvinylcyclotrisiloxane yielded a poly-(dimethylsiloxane-co-methylvinylsiloxane) with a low polydispersity (M h w/M h n ) 1.16), a controlled molar mass, and a uniform distribution of pendant vinyl groups along the chain. Vinyl-containing mesogenic molecules could be attached to the polysiloxane vinyl groups in a two-step hydrosilylation reaction by means of the coupling agent 1,1,3,3-tetramethyldisiloxane, yielding polymers with regularly spaced side groups. The flexible disiloxane link increases the mobility of the mesogenic moieties. In this study, 4-(n-undecyloxy)benzoic acid and the novel side group 4′-(n-undecyloxy)-4-biphenylcarboxylic acid were used as mesogens. The thermal behavior of the side-chain liquid-crystalline polymers was investigated by means of differential scanning calorimetry and optical microscopy.

A series of poly(styrene-block-ferrocenyldimethylsilane) copolymers (SF) with different relative molar masses of the blocks were prepared by sequential anionic polymerization. The bulk morphology of these polymers, studied by TEM and SAXS, showed well-ordered lamellar and cylindrical domains as well as disordered micellar structures. Temperature-dependent rheological measurements exhibited an order-disorder transition for SF 17/8 (the numbers refer to the relative molar masses in 10 3 g/mol) between 170 and 180°C, and an order-order transition for SF 9/19 between 190 and 200°C. The morphologies of binary blends of the diblocks with homopolymer were also investigated. In the blends the molar mass of the homopolymer was always less than the molar mass of the matching block. Ordered spheres on a bcc lattice and double-gyroid morphology were observed for the blends. The double-gyroid morphology was found only in F-rich diblock/homopolymer systems.

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