"The adsorption of aminoalkysilane coupling agents onto silica surfaces and the interaction of these functional silanes with a bismaleimide and an epoxy resin has been studied using solid-state NMR techniques. 13C CP-MAS was used to confirm the bonding between the silence and bismaleimide (BMI) resin and elucidate the nature of the crosslinking reaction of BMI. Deuterated coupling agents were synthesized and adsorbed on silica surfaces. The motional dynamics were probed using deuterium solid-echo NMR. It was determined that the motion of the alky portion of the coupling agents was consistent with gauche migrations (gtt ↔ tig) and pair gauche production (ttt ↔ g+tg-) conformational isomerizations.
In experimental lineshapes of the adsorbed animobutylsilane, at room temperature, were simulated using a two-site hop on the tetrahedral lattice, with an exchange rate of 8 x 105 sec-1 and a contribution from anisotropic rotation. The room temperature spectra of adsorbed aminobutylsilane bonded to a polymer (bismaleimide or epoxy) were calculated using a two-site diamond lattice model with an occupational probability of 0.7 to 0.3 and a jump frequency of 1.7 x 105 sec-1.
Over the temperature range -100 ⁰C to 85 ⁰C the types of motions of the coupling agent are not affected significantly, only the exchange rate between sites. The behavior of the interface in the presence of water was studied and showed an increase in the rate of motion of the probe molecule."Abstract, page iii.
Blum, Frank D.
Bertrand, Gary L.
Dharani, Lokeswarappa R.
M.S. in Chemistry
University of Missouri--Rolla
xi, 99 pages
© 1990 Joan E. Gambogi, All rights reserved.
Thesis - Restricted Access
Library of Congress Subject Headings
Polymers -- Spectra
Nuclear magnetic resonance spectroscopy
Solid state chemistry
Print OCLC #
Electronic OCLC #
Gambogi, Joan Ethel, "Molecular mobility in a model polymer composite" (1990). Masters Theses. 901.
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