• Jankovský, Ondřej
• Sedmidubský, David
• Pavlikova, Milena
• Lauermannová, Anna-Marie
• Antončik, Filip
• Lojka, Michal
• Pavlik, Zbysek

Abstract

Featured Application The data acquired from the conducted tests and analyses can be used in the design and development of energy-efficient low-carbon construction materials. Because magnesium oxybromide phases (MOB-318, MOB-518) are stable, non-defective and well densified, high mechanical resistance of MOB-based materials can be anticipated similarly to magnesium oxychloride cement (MOC). Analogous to MOC, precipitated MOB phases can accommodate a great volume of inorganic and organic fillers and aggregates, which enables the production of alternative construction materials for specific applications. MOB-based materials can thus meet specific technical, functional and performance criteria of building practice. As MOB-318 can transmit light, it can be used in the design of a novel, highly optically-transparent material for light-transmitting decorative panels, partition walls, facing panels, translucent bricks and other architectural elements. Another specific attribute of MOB is its marble-like appearance, which makes it suitable as a decorative material. MOB-based composites can also serve as flame retardants. As such, they can potentially find use in the form of insulation boards or ceiling slabs to ensure the fire safety of steel structure buildings. Abstract The search for environmentally sustainable building materials is currently experiencing significant expansion. It is increasingly important to find new materials or reintroduce those that have been set aside to find a good replacement for Portland cement, which is widely used despite being environmentally insufficient and energy-intensive. Magnesium oxybromides, analogues to well-known magnesium oxychloride cements, fit both categories of new and reintroduced materials. In this contribution, two magnesium oxybromide phases were prepared and thoroughly analyzed. The stoichiometries of the prepared phases were 5Mg(OH)(2).MgBr2.8H(2)O and 3Mg(OH)(2).MgBr2.8H(2)O. The phase analysis was determined using X-ray diffraction. The morphology was analyzed with scanning and transmission electron microscopy. The chemical composition was studied using X-ray fluorescence and energy dispersive spectroscopy. Fourier transform infrared spectroscopy was also used. The thermal stability and the mechanism of the release of gasses linked to the heating process, such as water and hydrobromic acid evaporation, were analyzed using simultaneous thermal analysis combined with mass spectroscopy. The obtained results were compared with the data available for magnesium oxychlorides.

Topics

• impedance spectroscopy
• morphology
• Carbon
• phase
• x-ray diffraction
• Magnesium
• Magnesium
• steel
• composite
• thermal analysis
• cement
• chemical composition
• transmission electron microscopy
• Fourier transform infrared spectroscopy
• evaporation