A ²⁹Si, ¹H, and ¹³C Solid-State NMR Study on the Surface Species of Various Depolymerized Organosiloxanes at Silica Surface.

ABSTRACT: Three poly(organosiloxanes) (hydromethyl-, dimethyl-, and epoxymethylsiloxane) of different chain lengths and pendant groups and their mixtures of dimethyl (DMC) or diethyl carbonates (DEC) were applied in the modification of fumed silica nanoparticles (FSNs). The resulting modified silicas were studied in depth using ²⁹Si, ¹H, and ¹³C solid-state NMR spectroscopy, elemental analysis, and nitrogen adsorption-desorption (BET) analysis. The obtained results reveal that the type of grafting, grafting density, and structure of the grafted species at the silica surface depend strongly on the length of organosiloxane polymer and on the nature of the "green" additive, DMC or DEC. The spectral changes observed by solid-state NMR spectroscopy suggest that the major

SUBMITTER: Protsak IS 

PROVIDER: S-EPMC6517472 | biostudies-literature | 2019 May

REPOSITORIES: biostudies-literature