Investigation of amorphous and crystalline phosphates in magnesium phosphate ceramics with solid-state H-1 and P-31 NMR spectroscopy

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68378297%3A_____%2F17%3A00473525" target="_blank" >RIV/68378297:_____/17:00473525 - isvavai.cz</a>

Výsledek na webu

<a href="http://www.sciencedirect.com/science/article/pii/S027288421730278X" target="_blank" >http://www.sciencedirect.com/science/article/pii/S027288421730278X</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.ceramint.2017.02.087" target="_blank" >10.1016/j.ceramint.2017.02.087</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Investigation of amorphous and crystalline phosphates in magnesium phosphate ceramics with solid-state H-1 and P-31 NMR spectroscopy

Popis výsledku v původním jazyce

Magnesium phosphate ceramics are chemically-bonded ceramics for bioengineering and civil engineering applications. Information about the nature of the reaction products, especially the amorphous fraction, and their role in the setting reaction, essential for linking reaction mechanisms to microstructure and performance of ceramics, is lacking. By exploiting 1H and 31P magic-angle spinning nuclear magnetic resonance spectroscopy, in addition to the crystalline reaction product (MKP), two amorphous phases, characterized by two distinct proton and phosphorous environments, have been identified. The results pointed to amorphous hydrated orthophosphate compounds which are the precursors of MKP. They show different 1H spin-lattice relaxation dynamics, and, higher water mobility with respect to MKP. Although these amorphous precursors should not be crypto-structural variants of MKP, they likely host similar structural units. Conversion into MKP is thought to occur through relatively minor rearrangements, as in Ca phosphate hydrates. The new information provided in this work allows us to propose a model for the setting reaction based on an existing theory involving a densification process, analogue to sol-gel processing of ceramics, coherent with results from small angle neutron scattering and mechanisms predicted by reaction kinetics analysis.

Název v anglickém jazyce

Investigation of amorphous and crystalline phosphates in magnesium phosphate ceramics with solid-state H-1 and P-31 NMR spectroscopy

Popis výsledku anglicky

Magnesium phosphate ceramics are chemically-bonded ceramics for bioengineering and civil engineering applications. Information about the nature of the reaction products, especially the amorphous fraction, and their role in the setting reaction, essential for linking reaction mechanisms to microstructure and performance of ceramics, is lacking. By exploiting 1H and 31P magic-angle spinning nuclear magnetic resonance spectroscopy, in addition to the crystalline reaction product (MKP), two amorphous phases, characterized by two distinct proton and phosphorous environments, have been identified. The results pointed to amorphous hydrated orthophosphate compounds which are the precursors of MKP. They show different 1H spin-lattice relaxation dynamics, and, higher water mobility with respect to MKP. Although these amorphous precursors should not be crypto-structural variants of MKP, they likely host similar structural units. Conversion into MKP is thought to occur through relatively minor rearrangements, as in Ca phosphate hydrates. The new information provided in this work allows us to propose a model for the setting reaction based on an existing theory involving a densification process, analogue to sol-gel processing of ceramics, coherent with results from small angle neutron scattering and mechanisms predicted by reaction kinetics analysis.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

20501 - Materials engineering

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

2017

Kód důvěrnosti údajů

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

Název periodika

Ceramics International

ISSN

0272-8842

e-ISSN

—

Svazek periodika

43

Číslo periodika v rámci svazku

8

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

9

Strana od-do

6571-6579

Kód UT WoS článku

000401401500100

EID výsledku v databázi Scopus

2-s2.0-85013460223