Quantitative SAXS analysis of oriented 2D hexagonal cylindrical silica mesostructures in thin films obtained from nonionic surfactants.

Oriented mesostructured surfactant-silica nanocomposite thin films with a 2D hexagonal mesostructure of cylindrical micelles were prepared by evaporation-induced self-assembly using two different nonionic Brij surfactants and studied by small-angle X-ray scattering in symmetric reflection (SRSAXS) and grazing incidence (GISAXS) geometries. A novel SRSAXS evaluation approach was applied that allowed a good fitting of the SRSAXS data over almost the whole range of scattering vectors. Aside from the cylinder radius and the lattice parameter, the approach provided accurate values for the polydispersity of the micelles, lattice distortions, and preferred orientation.

Functional nanocomposites prepared by self-assembly and polymerization of diacetylene surfactants and silicic acid.

Conjugated polymer/silica nanocomposites with hexagonal, cubic, or lamellar mesoscopic order were synthesized by self-assembly using polymerizable amphiphilic diacetylene molecules as both structure-directing agents and monomers. The self-assembly procedure is rapid and incorporates the organic monomers uniformly within a highly ordered, inorganic environment. By tailoring the size of the oligo(ethylene glycol) headgroup of the diacetylene-containing surfactant, we varied the resulting self-assembled mesophases of the composite material.

C-Cl/Si-H exchange catalysed by P,N-chelated Pt(II) complexes.

Alkyl chlorides R-Cl are dehalogenated by HSiMe2Ph in the presence of catalytic amounts of the complex [(kappa 2-P,N)-Ph2PCH2CH2NMe2]PtMeCl to give R-H and ClSiMe2Ph.