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Methane and adamantane based hyper-cross-linked polymers have been prepared by click chemistry reacting the corresponding tetraalkynes with 1,4-diazidobenzene. The adamantane based HCP proved to be very efficient for CO2capture at low pressures. [ABSTRACT FROM AUTHOR]

The utility of basic sites of porous coordination polymers (PCPs) for the end-functionalization of oligo(vinylidene fluoride) (OVDF) is demonstrated. Densely arranged carboxylate moieties on the PCP pore walls act as basic sites and allow the efficient elimination reaction of the terminal group of OVDF to proceed. The progress of the reaction of an OVDF precursor in the PCP nanochannels was evidenced using solid state 19F NMR spectroscopy. From 19F and 1H NMR and IR measurements of the product isolated from the composite obtained, the terminal –CH2CF2I moiety of OVDF was shown to be successfully converted to a –CHCF2group. Because of the large surface area of the PCP materials, the OVDF precursor easily accessed the basic sites, resulting in a large increase in the rate of the elimination reaction. In addition, a notable effect of the porous structure of PCPs upon the elimination reaction was observed. [ABSTRACT FROM AUTHOR]

Self-assembled supramolecular crystals fabricated by solvent-free mechanochemical treatments of a crystalline host and a rubbery polymer are stabilized by cooperative CHπ interactions as revealed by 1H fast-MAS and 2D solid state NMR. [ABSTRACT FROM AUTHOR]

Multinuclear 1H−13C heterocorrelated (HETCOR) NMR spectroscopy combined with X-ray diffraction revealed the unusual dual properties of identical guest molecules confined in two crystallographically distinct host cavities within single crystals based on hexagonal frameworks comprising guanidinium ions and organomonosulfonates. The environments of the two cavities differ substantially, as one is lined by the highly polar quasihexagonal guanidinium-sulfonate network, while the other is defined by walls consisting of nonpolar aromatic groups. The effect of these different environments on the NMR properties of the guest molecules is evident from chemical shift data and two-dimensional HETCOR spectra. The large magnetic susceptibility effect due to ring currents of the aromatic hosts enables determination of the host−guest distances and suggests intermolecular CH···π interactions. The 13C relaxation times reveal the molecular dynamics of the guests in two nanoscale environments that differ with respect to shape and dimensionality. [ABSTRACT FROM AUTHOR]

Nanocomposite micro-objects of mesoporous silica with polymers have been obtained by inclusion polymerization of vinyl monomers (styrene and methylmethacrylate) viaa radical process. The intimacy between the silica scaffold and the grown polymer has been addressed by a multi-technique approach and the extended interface has been recognized. In particular, phase-modulated Lee–Goldburg 2D heterocorrelated NMR was exploited to study the heterogeneous interfaces and the micro-adhesion between the inorganic matrix and the organic phase. By the in-depth characterization, it was possible to achieve a model in which polymer nanofibrils interact with the walls of the nanochannels in the mesoporous silica, resulting in interdigitated nanophases. A material consisting of two distinct phases so intimately entangled can explain the success of a replication process in which the morphology of the original material is entirely transposed to a polymeric material that fully retains its shape. The obtained micrometric shapes as well as their nanometric structure were directly observed, respectively, by scanning and transmission electron microscopies. [ABSTRACT FROM AUTHOR]

Dipeptide crystals containing nanochannels of various sizes show remarkable and selective absorption of methane, carbon dioxide and hydrogen. [ABSTRACT FROM AUTHOR]

Diphenylene moieties, molecularly ordered in the framework of periodic mesoporous organosilicas, behave as molecular rotors and show a mobility with correlation times as short as a few nanoseconds. [ABSTRACT FROM AUTHOR]

A porous single-crystal collects xenon atoms from the gas phase and orients them macroscopically, as highlighted by hyperpolarized xenon NMR. [ABSTRACT FROM AUTHOR]