Sulfates-based nanothermites: an expanding horizon for metastable interstitial composites.
Angew Chem Int Ed Engl
; 54(15): 4458-62, 2015 Apr 07.
Article
em En
| MEDLINE
| ID: mdl-25702633
ABSTRACT
Metal sulfates (Ba, Bi, Ca, Cu, Mg, Mn, Na, Zn, Zr) were used as oxidizers in reactive compositions with Al nanopowder. These new kinds of nanothermites have outstandingly high reaction heats (4-6â
kJ g(-1) ) compared to conventional Al/metal oxides (1.5-4.8â
kJ g(-1) ) and also have good combustion velocities (200-840â
m s(-1) vs 100-2500â
m s(-1) ). These compositions are extremely insensitive to friction making their preparation and handling easy and safe. The sulfate hydration water increases the reaction heats and has a significant effect on the sensitivity to impact and to electrostatic discharge. The reaction of Al with water is easier to initiate than the one with sulfate which leads to two possible decomposition modes for samples exposed to an open flame. The pyrotechnical properties observed with sulfates have also been found for other sulfur oxygenates (SO3 (2-) , S2 O3 (2-) , S2 O8 (2-) ) which opens up new horizons in the domain of metastable interstitial composites.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Angew Chem Int Ed Engl
Ano de publicação:
2015
Tipo de documento:
Article