The magnesium carbonate is a kind of functional filler. According to the thermal decomposition theory, it will emit water and carbon dioxide during pyrolysis. Through the industrial application, it has proved that the magnesium carbonate filler is effective and economical. The thermal decomposition of magnesium carbonate can release 60 percent of water of hydration and carbon dioxide. It can be seen in the two TGA peaks which are in the 445°F and 750°F.
The carbon dioxide is about 25(weight). The particle size, purity and density have a wide selectable range. The particle size of magnesium carbonate will affect the emission of smog. The finer particle size can improve the filler’s dispersibility in the polymer. After treated by stearic acid, various of magnesium carbonate can be used for further improve the miscibility.
The basic magnesium carbonate can replace whiting, and make the chlorosulfonation monomeric compound with low smoke and flame retardant property. Replacing white jade, the magnesium carbonate can cause lower smoke density under circumstance of not only the flame but also the smouldering. Furthermore, it can increase the double time of maximum smoke density.