Physical and chemical properties of brucite

White, gray white, when Fe, Mn mixed with green, yellow or brown red, fresh surface and broken glass luster, cleavage surface pearl luster, fibrous brucite silk gloss; transparent. Cleavage {0001} is very complete. The hardness is 2.5. The flakes are flexible and flexible. Relative density 2.3~2.6. It has thermoelectric properties. The whiteness of the massive brucite can reach 95%.

Under the polarizing microscope, the interference interference is reddish brown instead of the first grade yellow or orange. The ductility can be negatively affected by the effect of stress. One axis crystal (), but can show two axis crystal. The refractive index is Ne=1.5705~1.5861, No=1.5612 ~1.570, and the difference between Ne and No after heating is smaller.

Mechanical properties: the tensile strength of brucite is 902MPa, which belongs to medium strength fiber material. The modulus of elasticity is 13800MPa, and it has some brittleness. The hardness of Vivtorinox is 50.4~260.5 and has obvious anisotropy. It is easy to grind into fine particles. The relative density of the theory is 2.39.

Electromagnetic properties: the resistivity of brucite is anisotropic, and the resistivity increases when heated. The dielectric constant is 4.7~5.4 (1MHz); under the condition of low frequency (50Hz) and medium frequency, the dielectric constant increases, and it has obvious directionality, and the dielectric loss angle tangent is 0.105. The dielectric constant and dielectric loss tangent increased by 54% and 2.7 times respectively.

Thermal performance: the reliable use temperature of brucite is 400 C. The thermal conductivity of brucite is 0.46W/m. K and the loose fiber is 0.131~0.213W/m. K (volume density is 0.47 g/cm3). The thermal expansion of brucite is 16.7*10-7/ degrees C, and the transverse temperature is 8.8*10-7/ C, and the thermal expansion behavior is basically linear. Brucite also has the properties of flame retardant, resistance to open flame and high temperature flame. The decomposition temperature of brucite is 450.

Chemical properties: brucite is the best alkali resistant natural inorganic fiber. But it can be dissolved completely in strong acid. It can be dissolved at different speed in oxalic acid, citric acid, acetic acid, mixed acid and Al (OH) 3 solution. In humid or rainy climates, brucite is vulnerable to atmospheric CO2, H2O erosion, so brucite products need waterproof coating.

Surface properties: the diameter of single brucite fiber measured by transmission electron microscope is 0.54~0.86 m, and the finest is 0.086 m. The electric potential of brucite can reach 36.3mV. The pH value of the zero potential point is 12.5. Brucite fiber has good splitting and dispersibility, and long fiber. After beating or chemical dispersing, the beating degree can be obviously improved, and it can be used for wet spinning and papermaking.