Solid‐state NMR tools for the structural characterization of POSiSils: 29Si sensitivity improvement with MC‐CP and 2D 29Si–29Si DQ‐SQ at natural abundance. (8th November 2018)

• Record Type: Journal Article
• Authors: Smet, Sam; Verlooy, Pieter; Saïdi, Fadila; Taulelle, Francis; Martens, Johan A.; Martineau‐Corcos, Charlotte
• Other Names: Baias Maria guestEditor.
• Is Part Of: Magnetic resonance in chemistry. Volume 57:Number 5(2019)
• Page Start: 224
• Page End: 229
• Publication Date: 2018-11-08
• Subjects: 29Si NMR -- DQ‐SQ NMR -- MC‐CP -- NMR crystallography -- polyoligosiloxysilicone -- POSiSils; Nuclear magnetic resonance spectroscopy -- Periodicals; Chemistry, Organic -- Periodicals; Magnetic resonance -- Periodicals; 538.36
• DOI: 10.1002/mrc.4800
• Languages: English
• ISSNs: 0749-1581

Abstract

Abstract: The 1 H– 29 Si multiple‐contact cross polarization (MC‐CP) MAS NMR experiment is evaluated for the class of silicate‐siloxane copolymers called POSiSils, that is, polyoligosiloxysilicones. It proves a reasonably good solution to tackle the challenge of recording quantitative 29 Si NMR data in experimental time much reduced compared with single pulse acquisition. In a second time, we report 29 Si– 29 Si MC‐CP double‐quantum single‐quantum (MC‐CP‐DQ‐SQ) NMR experiment, which provides information about the through‐space proximities between all silicon species despite the high degree of heterogeneity of this material. This work furthers the NMR tools for NMR crystallography for inorganic polymers, as it covers flexible polymers with different dimensionalities and long or heterogeneous relaxation characteristics at low 29 Si natural abundance. Abstract : The NMR toolbox for NMR crystallography of POSiSils is expanded: the 1 H → 29 Si MC‐CP provides nearly quantitative information about the various silicon species in the materials, whereas the 2D 29 Si– 29 Si MC‐CP DQ‐SQ provides information about the connectivity between the species. These data will help understanding the structure of this new class of materials.