Four application fields and characteristics of nano barium sulfate
Four application fields and characteristics of nano Barium sulfate
Barium sulfate is an important inorganic chemical raw material. It not only has good optical properties and chemical stability, but also has special characteristics such as volume, quantum size and interface effect. Therefore, it is widely used in coatings, plastics, paper, rubber, ink pigments, etc. field is widely used. nano barium sulfate has the advantages of high specific surface area, high activity, good dispersibility, etc. It can show excellent performance when applied to composite materials.
1. Plastic industry
Adding nano barium sulfate to polymers to obtain composite materials with high strength and high toughness has attracted more and more attention. For example, barium sulfate can be added to polyethylene (PE), polypropylene (PP), polylactic acid (PLA). ), polytetrafluoroethylene (PTFE) and other materials, especially after the surface modification of barium sulfate, its mechanical properties have been significantly improved.
For most polymer composite materials, with the increase of the amount of modifier, the strength and toughness of the composite material increase first and then decrease, this is because the excessive amount will cause multi-layer physical adsorption on the surface of nano barium sulfate. , making the agglomeration in the polymer serious, affecting the mechanical properties of the composite material, and making it difficult to exert the excellent characteristics of the inorganic filler; a small amount of modifier will make the connection interface between the nano-barium sulfate and the polymer. The increase of defects leads to the decrease of the mechanical properties of the composites.
In addition to the above-mentioned amount of surface modifier has a great influence on the mechanical properties of composites, the amount of barium sulfate is also an important factor. This is because the strength of nano-barium sulfate is very large, and it can play a supporting role when added to the composite material, thereby producing a certain strengthening effect. However, when the content of nano-barium sulfate is too high (over 4%), the agglomeration phenomenon in the composite material and the addition of inorganic particles increase the matrix defects, making the composite material easier to break, thereby changing the mechanical properties of the composite material. Difference. Therefore, the amount of barium sulfate added must be within the range of its suitable mechanical properties.
2. Coating industry
As an extender pigment, barium sulfate is widely used in coatings, and plays a very important role in improving the thickness, wear resistance, water resistance, heat resistance, surface hardness, and impact resistance of the coating film. In addition, due to its low oil absorption and high filling amount, it can be used in water-based coatings, primers, intermediate coatings, and oil-based coatings to reduce coating costs and replace 10% to 25% of titanium dioxide in water-based coatings. , the results show an increase in whiteness without a decrease in hiding power.
The characteristics of ultra-fine barium sulfate for coatings: 1) The particle size is very fine and the particle size distribution is narrow; 2) It has transparency when dispersed in the resin liquid; 3) It has good dispersibility in the coating base material; 4) It is compatible with organic coloring pigments It has the function of dispersing aid; 5) can improve physical properties.
3. Paper industry
Barium sulfate has the advantages of good physical and chemical stability, moderate hardness, high whiteness, and can absorb harmful rays, so it is often used in the paper industry.
For example, carbon paper is a common study and office supplies, but its surface is easy to decolorize. Therefore, barium sulfate is required to have a high oil absorption value, which can improve the ink absorption of the paper. The resulting wear is small.
4. Chemical fiber industry
Viscose fiber, also known as "rayon", has similar properties to natural cotton fibers, such as antistatic, good hygroscopicity, easy dyeing, and easy textile processing. And nano barium sulfate has good nano effect. The nano barium sulfate/regenerated cellulose blend fiber made of the two as raw materials is a new type of composite fiber, which can maintain the unique properties of each component, and through mutual interaction The "synergy" between them makes up for the shortcomings of a single material and shows new properties of composite materials.