A novel route to obtain highly ordered self-assembled honeycomb films has been investigated by a bottom-up process. A polymer with one chain end ionic functionality has been synthesized in a one-step reaction by nitroxide-mediated polymerization. This ionomer synthesis represents a very simple way, and honeycomb structured films have been observed after solvent evaporation in a long-range distance of few hundred microns in a very regular ordered arrangement. These films are simply prepared by spreading out polymers CS 2 solutions without additives over various substrates as well on inorganic surfaces as onto different polymeric substrates such as flexible PVC sheet or rigid PMMA plate. Different experimental parameters, such as polymer concentration or wet thickness, have been checked to tune the pores size and thus the honeycomb morphologies. An elegant technique based on reflected and transmitted light has been used to correlate the pores size inside and on the top of the film. This highly ordered hexagonal pattern on the polymeric surfaces suggests the possibility of taking advantage of the microtextures for inducing optical interferences but also to modify the color of this bioinspired material as a function of their visual angle as in nature.

Coating of silica nanoparticles by biocompatible and biodegradable polymers of ε‐caprolactone and L‐lactide was performed in situ by ring‐opening polymerization of the cyclic monomers with aluminum, yttrium, and tin alkoxides as catalysts. Hydroxyl groups were introduced on the silica surface by grafting of a prehydrolyzed 3‐glycidoxypropyl trimethoxysilane to initiate a catalytic polymerization in the presence of metal alkoxides. In this manner, free polymer chains were formed to grafted ones, and the graft density was controlled by the nature of the metal and the alcohol‐to‐metal ratio. The grafting reaction was extensively characterized by spectroscopic techniques and quantified. Nanocomposites containing up to 96% of polymer were obtained by this technique. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 1976–1984, 2004

Summary: The grafting of poly(ethylene oxide) (PEO) onto silica nanoparticles was performed in situ by the ring‐opening polymerization of the oxirane monomer initiated from the mineral surface using aluminium isopropoxide as an initiator/heterogeneous catalyst. Alcohol groups were first introduced onto silica by reacting the surfacic silanols with prehydrolyzed 3‐glycidoxypropyl trimethoxysilane. The alcohol‐grafted silica played the role of a coinitiator/chain‐transfer agent in the polymerization reaction and enabled the formation of irreversibly bonded polymer chains. Silica nanoparticles containing up to 40 wt.‐% of a hairy layer of grafted PEO chains were successfully produced by this technique.

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A colored polymer/aluminium hybrid pigment was synthesized by nitroxide mediated polymerization initiated from an inorganic surface. This approach requires the preparation of a vinyl dye monomer able to copolymerize with n‐butyl acrylate (n‐BuA) and styrene (S) from the surface of aluminium flakes. The linearity of the ln([M]0/[M]t) and of the $\overline M _{\rm n}$ as a function of time and conversion constitute the criteria of control/“living” polymerization, i.e. linearity of respectively ln([M]0/[M]t) = f(t) and the $\overline M _{\rm n}$ = f(conversion) plots. Kinetic measurements reveal an upward deviation from the linearity for n‐BuA polymerization for very high conversion. The introduction of S monomer restores the control of the polymerization. Both the length of the grafted chains and the dye/styrene molar ratio influence the color of the hybrid material.magnified image