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The fabrication of supramolecularly engineered two-dimensional (2D) networks using simple molecular building blocks is an effective means for studying host–guest chemistry at surfaces toward the potential application of such systems in nanoelectronics and molecular devices. In this study, halogen-bonded molecular networks were constructed by the combination of linear halogen-bond donor and acceptor ligands, and their 2D structures at the highly oriented pyrolytic graphite/1-phenyloctane interface were studied by scanning tunneling microscopy. The bi-component blend of the molecular building blocks possessing tetradecyloxy chains formed a lozenge structure via halogen bonding. Upon the introduction of an appropriate guest molecule (e.g., coronene) into the system, the 2D structure transformed into a hexagonal array, and the central pore of this array was occupied by the guest molecules. Remarkably, the halogen bonding of the original structure was maintained after the introduction of the guest molecule. Thus, the halogen-bonded molecular networks are applicable for assembling guest species on the substrate without the requirement of the conventional rigid molecular building blocks with C3 symmetry.

The photosensitivity of cardanol has been evaluated using a multi-technique approach. Among other techniques, size exclusion chromatography, matrix assisted laser desorption ionization mass spectrometry and their off line coupling provided useful details on the macroscopically observed yellowing and insolubility of cardanol under UV activation by analyzing photoproducts at the molecular level. Evidencing the implication of the unsaturations borne by the cardanol side chain in a crosslinking process, an original synthesis route leading to its complete methoxylation has been proposed as a way to lower the photosensitivity of cardanol. Using a similar set of analytical techniques, this newly synthesized methoxylated cardanol has appeared more resistant towards UV exposure, without any crosslinking but a simple dimerization preserving its solubility. As a direct application, copolymers made from methyl methacrylate, cardanol and methoxylated cardanol have been synthesized, and their photocrosslinking ability was found to depend on the content of the two latter co-monomers, as a preliminary step towards the production of photocrosslinkable bio-based polymers with a tunable UV curing propensity.

The efficiency of a flame retardant coating based on poly(allylamine) (PAH) and montmorillonite (MMT), deposited on polyamide 6 (PA6) bulk polymer was demonstrated in our previous work. In this paper we aim to investigate the mechanism of action of this flame retardant coating. To reach this objective, PA6-(PAH-MMT) at 40 bilayers was tested in a cone calorimeter and interrupted at different characteristic times: 25 s (after the fire test start), time to ignition, time of peak heat release rate and time of flameout. The condensed phases of the specimen residues obtained were characterized by scanning electron microscopy, X-ray diffraction, laser desorption ionization and solid state 13C nuclear magnetic resonance while the gas phase was evaluated by thermogravimetric analysis coupled with infrared spectroscopy and mass spectrometry. Finally the pyrolysis combustion flow calorimeter was used to evidence the effect of this layer-by-layer assembly in the gas phase. A possible mechanism explaining the improvement of the flame retardancy of a PA6 substrate in the presence of LbL coating made of PAH and clay is proposed.

Plasma polymer thin films are of great interest in surface engineering in a wide range of applications. Herein, by using soft atmospheric plasma deposition parameters and by adapting these conditions to the used perfluorodecyl and dodecyl acrylates precursors, it is possible to get a high retention of monomer functionalities and a polymerization close to conventional methods. Molecular investigation revealed the presence of polymeric moieties and the mechanism of plasma polymerization has been mainly based on the polymerization by activation of the ethylenic groups. X-ray diffraction analyses have shown the presence of a smectic lamellar where the polyacrylate backbone was the amorphous phase and fluorinated and alkyl side chains were the hexagonal crystalline section. Wetting properties have been evaluated and finally showed hydrophobic surfaces