Messi Biology said, magnesium carbonate is a functional filler, based on the principle of thermal decomposition, when pyrolysis, it will release hydrated water, and carbon dioxide. Through industrial applications, magnesium carbonate filler has proven to be effective and cost effective. The thermal decomposition of magnesium carbonate will release 60% by weight of hydrated water and CO2, as seen by the two TGA peaks at 445°F and 750°F.
CO2 is approximately 25 (wt). A wide range of particle size, purity and density options are available for the carbonates. The particle size of the magnesium carbonate affects the release of smoke. There are 50 of ultrafine grades of magnesium carbonate with particle sizes less than 1 micron that have lower Dm values than the standard values for flame burning and fuming combustion, and a medium particle size of 2 to 3 microns is used in the standard. A blend made by adding 25 parts of ultra-fine grade magnesium carbonate to 100 parts of hard PVC gave Dm values of 300 and 168 for flame and smoke burning, respectively, compared to 450 and 180 for the standard grade. finer particle size improves the dispersion of the filler in the polymer, and various grades of magnesium carbonate treated with stearic acid can be used to further improve blending.
Replacement of chalk with alkaline magnesium carbonate provides low smoke and flame retardant properties to the chlorosulfonated monomer compounds. Substitution of alkali magnesium carbonate for white chalk results in a significant reduction in smoke density, both in flame burning, and in fuming combustion. Further, the use of alkaline magnesium carbonate increases the time to maximum smoke density by a factor of two.