A solid state NMR and in-situ infrared spectroscopy study on the setting reaction of magnesium sodium phosphate cement

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68378297%3A_____%2F18%3A00490198" target="_blank" >RIV/68378297:_____/18:00490198 - isvavai.cz</a>

Výsledek na webu

<a href="https://doi.org/10.1016/j.jnoncrysol.2018.06.006" target="_blank" >https://doi.org/10.1016/j.jnoncrysol.2018.06.006</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.jnoncrysol.2018.06.006" target="_blank" >10.1016/j.jnoncrysol.2018.06.006</a>

Jazyk výsledku

angličtina

Název v původním jazyce

A solid state NMR and in-situ infrared spectroscopy study on the setting reaction of magnesium sodium phosphate cement

Popis výsledku v původním jazyce

In the present work, the setting reaction of magnesium sodium phosphate cement was followed in time with insitu attenuated total reflectance Fourier-transform infrared spectroscopy and solid state nuclear magnetic resonance spectroscopy, in order to gain insights into the products and phase transformations. The results indicated that, during the progress of the reaction, amorphous phases containing the H2PO4 − structural group converted into phases containing HPO42− and finally PO4 3−. The increase in pH triggered by the MgO dissolution was considered as the driving force for the transformations. This is supposed to promote the establishment of a high degree of supersaturation close to the surface of MgO grains, resulting in kinetically driven transformations and favouring the amorphous nature of the products. It is suggested that in the later stages of the reaction, two orthophosphate amorphous phases, hosting bound water molecules, coexisted, with the one showing a relatively more ordered 31P local environment, converting into a second with a more disordered phosphorous environment. The densification of the ceramic can be considered as a structural reorganization encompassing bonding of water molecules into a pervasive amorphous phase, containing magnesium-phosphate structural units and involving limited structural rearrangements of the local environment of P and, especially, of Na.

Název v anglickém jazyce

A solid state NMR and in-situ infrared spectroscopy study on the setting reaction of magnesium sodium phosphate cement

Popis výsledku anglicky

In the present work, the setting reaction of magnesium sodium phosphate cement was followed in time with insitu attenuated total reflectance Fourier-transform infrared spectroscopy and solid state nuclear magnetic resonance spectroscopy, in order to gain insights into the products and phase transformations. The results indicated that, during the progress of the reaction, amorphous phases containing the H2PO4 − structural group converted into phases containing HPO42− and finally PO4 3−. The increase in pH triggered by the MgO dissolution was considered as the driving force for the transformations. This is supposed to promote the establishment of a high degree of supersaturation close to the surface of MgO grains, resulting in kinetically driven transformations and favouring the amorphous nature of the products. It is suggested that in the later stages of the reaction, two orthophosphate amorphous phases, hosting bound water molecules, coexisted, with the one showing a relatively more ordered 31P local environment, converting into a second with a more disordered phosphorous environment. The densification of the ceramic can be considered as a structural reorganization encompassing bonding of water molecules into a pervasive amorphous phase, containing magnesium-phosphate structural units and involving limited structural rearrangements of the local environment of P and, especially, of Na.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

20504 - Ceramics

Projekt

<a href="/cs/project/LO1219" target="_blank" >LO1219: Udržitelný pokročilý rozvoj CET</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2018

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of Non-Crystalline Solids

ISSN

0022-3093

e-ISSN

—

Svazek periodika

498

Číslo periodika v rámci svazku

October

Stát vydavatele periodika

NL - Nizozemsko

Počet stran výsledku

11

Strana od-do

49-59

Kód UT WoS článku

000440389500007

EID výsledku v databázi Scopus

2-s2.0-85048578377