Talc is a kind of magnesium silicate mineral, belonging to trioctahedron mineral, its structural formula is (Mg6)[Si8]O20(OH)4. Talc is generally lumpy, leaf-like, fibrous or radial, and has a slippery feel. It has the characteristics of low hardness and high melting point.
Talc has good electrical and thermal insulation, low expansion and shrinking power, high dispersion, strong hiding power, good oil absorption and hydrophobicity, large slipperiness, low friction coefficient, stable chemical properties, resistance to acid and alkali corrosion . Because of its stable chemical properties, it is widely used in papermaking, chemical, paint, ceramic, cable, rubber and other industries.
Calcium carbonate is an inorganic compound with the molecular formula CaCO₃. Commonly known as: limestone, marble, calcite. It is an inorganic compound, neutral, basically insoluble in water, soluble in hydrochloric acid. Its points. Types of industrial calcium carbonate: heavy calcium carbonate (heavy calcium), active calcium carbonate (active calcium), light calcium carbonate (light calcium), nano calcium carbonate (nano calcium).
Heavy calcium products are mainly used in the papermaking, rubber and plastic industries, and the filling amount is generally large, mainly as volumetric fillers to reduce the manufacturing cost of applied products. Light calcium products have a relatively wide range of applications, mainly based on volume filling. Nano calcium carbonate products are often used as functional fillers such as modification or reinforcement in the application process, and the filling amount is generally small. The main application areas of light calcium carbonate products are plastics, rubber, coatings, adhesives and inks.
From the above introduction, it can be seen that both talc powder and calcium carbonate powder are mainly used as fillers, and their main functions are as follows:
1. Reduce the shrinkage of the material (that is, reduce the geometric deformation).
2. Increase the stiffness and heat resistance of the material.
3. Reduce material production costs.
Differences in application characteristics of talcum powder and calcium carbonate powder:
The shape of talc is flake, so it has higher rigidity, dimensional stability and heat resistance temperature, and it has a good reinforcement effect. Calcium carbonate is generally granular, so its stiffness and other aspects are not as good as talc, but its price is lower, and its whiteness is high, and it has little effect on the impact toughness of plastics.
Talc has a nucleation effect on polypropylene, while calcium carbonate has no obvious effect in this respect. Calcium carbonate can generally be divided into light calcium carbonate and heavy calcium carbonate, but talc powder does not have this distinction, talc powder is ground from natural minerals.