Multinuclear Solid-State NMR Study of Hybrid Coatings for Oxygen Barrier Properties.

This work aims at investigating by means of solid-state NMR the molecular structural and dynamic properties of hybrid coatings obtained by the sol-gel method by reacting tetraethoxysilane (TEOS) with trialkoxysilane terminated polyethylene-b-poly(ethylene glycol) copolymer (PE-PEG-Si) with different amounts of PHS [poly(4-hydroxystyrene)] added. Quantitative structural information concerning the silicon connectivity and the silica condensation degree could be derived from 29Si DE-MAS spectra and interesting information concerning hydrogen-bonds have been obtained from 1H-MAS spectra. Moreover differences in the conformational properties and crystallinity of the organic components in the different samples have been revealed by means of 13C quantitative DE-MAS and selective CP-MAS experiments. Correlations between molecular properties and oxygen barrier performances have been hypothesized on the basis of the solid-state NMR results.