There are more than a thousand talc production processing enterprises in China, but no more than 10 enterprises can produce fully qualified molecular compounds for plastic talc. There are no more than 15 companies that can produce basic qualified products. At present, China's more capable manufacturing enterprises focus on the production of export products seriously ignore the growing domestic demand. A large part of the talc used in the domestic molecular compound plastics industry comes SMEs informal enterprises. This makes it difficult to guarantee product quality. At the same time, it is worth mentioning that the origin of some talcum powders used in scientific research in China is also very uncertain, which greatly reduces the credibility of its research conclusions.
Talc has a significant strengthening effect on molecular compound plastics, but all talc products have a strengthening effect. Enhancement effects vary significantly with product grade. It is difficult to propose uniform specific standards for talc used in the molecular compound plastics industry. The general principle is: try to use pure talc products with the appropriate particle size, the product does have to be as fine as possible. In view of the diversity of talc mines, the technical support of manufacturers is needed to obtain the effect. When selecting products, at least the "four degrees" of talc should be considered, that is, purity, whiteness, fineness, flake.
Purity refers to the talc content of the product. Talc is contained in nature in industrial production, 100% pure talc products in the industry cannot exist. There is no doubt that the higher the purity of talc, the better its strengthening effect. Studies have shown that certain impurities in talc only reduce the purity, but also have a significant effect on the performance of the final product.
There are two types of whiteness in the talc test: narrow broad. Narrow whiteness is the general definition of whiteness, which can be expressed by blue light whiteness, Ganz plastic characteristic whiteness, Hunter whiteness. There are no less than a hundred formulas for calculating whiteness in the world, no less than 10 formulas often used in the non-metallic mineral light industry. Broad whiteness includes dry whiteness, wet whiteness, hue. For the same raw material, the finer the particle size, the higher the whiteness. The higher the moisture, the lower the whiteness. Although the degree of whiteness has little effect on the physical properties of the product, it is very important to maintain the purity of the color for light-colored products.
Third, the degree
The significant strengthening effect of talc on molecular compound plastic products mainly comes its peculiar micro-flaky structure. The more complete the talc powder's flake structure, the more obvious its strengthening effect. The two main factors affecting the flaky shape of the product are: talc purity powder processing methods skills.
Micronization is the development trend of talc products. The finer the product, the better the strengthening effect, but at the same time the surface energy of the particles increases, it is easy to agglomerate, separation is difficult, the price is high. Therefore, it is necessary to products with appropriate fineness according to their own skill level actual needs. It is necessary to be as fine as possible.
Generally speaking, to evaluate the advantages disadvantages of a talc product, at least the above four aspects must be considered. Judging quality with only one indicator is one-sided incomplete. If someone only judges the quality of talc products based on the average particle size, this is very questionable.