A multinuclear solid‐state magnetic resonance study of the interactions between the inorganic and organic coatings of BaSO₄ submicronic particles

Abstract

Silica-coated BaSO4 submicronic particles, modified on the surface by treatment with stearic acid, have been characterized by means of 29Si, 13C, and 1H magic-angle-spinning (MAS) high-resolution techniques, and low-resolution 1H-FID analysis. Two types of adsorbed water were identified; adsorbed either inside or on the surface of BaSO4, most of the latter being removed by the silica coating. Evidences of silica-stearic acid interactions were found involving either carboxylic acid or carboxylate functional groups, and occurring by means of hydrogen and/or covalent bonds. Stearic acid was present as monolayer only, its chain being mostly rigid, even though a small fraction was subjected to fast inter-conformational motions.

Solid State NMR Spectroscopy

“…Another area of study in which SSNMR has been widely applied is inorganic solids. Recent examples of the applicability of solid-state NMR spectroscopy to structural studies of inorganic solids include investigations of Ta oxyfluoride materials , binary transition-metal phosphides , silica-coated BaSO 4 submicronic particles , and CaSiO 3 polymorphs . SSNMR is also very useful for characterization of organometallic compounds and inorganic−organic hybrid materials.…”

Formation of the modified ultrafine anatase TiO2 nanoparticles using the nanofiber as a microsized reactor

“…In academia and industry, a large number of inorganic nanoparticles are often added as fillers into organic materials to make the products have optical, 1 mechanical, 2 thermal, 3 magnetic, 4 and other properties. 5 For example, the crystalline titanium dioxide (TiO 2 ) is often introduced into polyethylene terephthalate (PET) substrate to improve the mechanical properties and ultra-violet protection factor (UPF) of PET fiber.…”