Organically modified clays are largely employed in the preparation of nanostructured materials. The structural and dynamic characterization of the clay surface appears very important in the perspective of understanding the molecular mechanisms determining the improvement of the material properties. To this aim, in this work, a synthetic clay, Laponite, was studied in its untreated hydrophilic Na+-form, after ion exchange with alkylammonium cations and after subsequent grafting reaction with an alkoxysilane. These three samples were characterized by IR, SEM, TGA, and X-ray techniques and were deeply investigated by means of a wide combination of 29Si, 13C, and 1H high- and low-resolution solid-state NMR experiments. The grafting reaction with alkoxysilanes, occurring at the clay platelet edges, resulted in a reduction of the clay inter-platelet distances, and in an increased disorder in both the arrangement of the platelets and the conformational structure of the intercalated organic cation chains, probably due to the relative twisting of adjacent platelets.

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Nitroxyl radicals were used as functionalizing agents during the free radical postreactor modification process of polyolefins carried out in the melt. The 4‐hydroxy‐2,2,6,6‐tetramethylpiperidine‐1‐oxyl (HO‐TEMPO) and the 4‐benzoyloxy‐2,2,6,6‐tetramethylpiperidine‐1‐oxyl (BzO‐TEMPO) free radicals were successfully grafted onto a polyethylene‐based material (ethylene‐co‐1‐octene copolymer) by coupling reaction with polymer macroradicals; these last were formed by H‐abstraction through peroxide addition. The macromolecular structure of the functionalized polyolefins was assessed by 1H‐NMR, FTIR spectroscopy, and SEC measurements which were used to evidence the grafting site, to evaluate the grafting level and to highlight the occurrence of chain extension through crosslinking side reactions. Indeed the use of proper model compounds allowed the preparation of accurate FTIR calibration curves for the quantitative determination of the functionalization degree. Besides the high temperature SEC analysis highlighted that this fast and simple coupling reaction between macroradicals and nitroxyl free radicals grants the grafting of functionalities onto the polyolefin backbone by contemporarily preventing the side reactions liable of the structure and MW modification of the pristine polymer. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011

Proteins from legumes are suitable to produce thermoplastic biopolymeric materials if isolated at purity higher than 60%. In fact, under this circumstance, they can be denaturized without degrading and thus are suitable for extrusion processing. © 2018 Society of Chemical Industry.