Mica powder is currently mainly used in:
(1) Oil drilling mica slurry. Used as drilling water-based mud additive to increase the adhesion of the mud on the hole wall and block the weakly permeable formation. From the perspective of product types, this market is relatively special and requires the lowest quality of mica, so the materials used are cheap.
(2) Pigment. Mica powder is widely used in latex to improve paint quality, such as increasing surface finish, prolonging durability, and chemical resistance. Because mica does not deform in the sun, it helps to control the fluidity of the paint and improve the scrubbing resistance. One of the most important characteristics of mica in paint is that the plane of the small chip and the base layer are arranged in a plane to improve viscosity, prevent the intrusion of water and dissolved oxides and sulfate ions, improve durability, and prevent rust. The plane sheet arrangement level of mica particles constitutes an isolation barrier. While blocking the intrusion of oxygen, this isolation barrier also creates a swirling diffusion channel for the escape of volatile substances. Generally speaking, the pigment industry is the largest user of wet mica.
(3) Pearlescent pigments. Pearlescent pigments artificially generate "mother-of-pearl" effect or pearl luster by light transmission, reflection and interference. In order to achieve this light interaction effect, mica is used as a substrate and a thin layer of titanium dioxide is coated on it. According to the desired effect, either muscovite or phlogopite can be used. The automobile industry is the main market for pearlescent pigments. In Japan, pearlescent pigments are also used in roofing materials, computer housings and TV housings.
(4) Structural coatings. The ground mica powder can be used as a reinforcing filler for structural coating gypsum. Its main performance is to control shrinkage and cracks and maintain plasticity.
(5) Mica reinforced plastic. Mica can improve the dimensional stability of the polymer. After being modified by a coupling agent, it can be mixed with thermoplastic resin or thermosetting resin to make mica reinforced plastic. The main properties of this plastic are: ① The tensile and flexural modulus are significantly increased, while the tensile and flexural strength are increased, and the elongation is reduced. ②Reduce thermal expansion, and the flat nature of mica prevents non-uniform shrinkage, while plastic tends to cause wrinkles. ③The larger the amount of mica, the higher the heat distortion temperature. The plane arrangement of mica pieces increases impermeability and impermeability. ④Improve the insulation of plastics. ⑤Inertness to ultraviolet rays, microwaves and most chemical reagents. The filling amount of reinforced plastic mica is generally 40%, and a coupling agent is required for modification. Reinforced plastics are mainly used in the automotive industry, such as lampshades, car interior decoration, baffle elements, air-conditioning and heater valve housings, as well as microwave ovens, air-conditioning fan pages, etc.
(6) Welding rod. Mica can be used as a component of titanium electrode for welding low-carbon steel and ordinary steel. It can prevent cracks and control the dosage of flux. The flux is coated on the metal electrode. Due to the development of welding technology, the demand is on the decline.
(7) New building materials. Mica powder is an important raw material for new building materials, especially mica powder is used to replace asbestos to produce "mica calcium silicate board", "mica fiber cement mid-wave tiles", "mica light bricks" and other new building materials. It has excellent performance such as heat insulation, sound insulation and quality light and weathering resistance.
(8) Thermal insulation and anti-static pressure board. The author developed a mica + carbonate rock + clay high temperature resistant, insulating and anti-static plate to replace asbestos plate under high temperature and medium pressure conditions.
(9) Mica paper. Mica paper is a main way for the comprehensive utilization of mica powder. In future research, we should focus on the research on the influence of mica phosphor size, mica paper type and mica content on the electrical and mechanical properties of mica insulation, further improve the performance of mica paper, and develop thin specifications, thick specifications, high dielectric strength, high tensile strength and high permeability mica paper.
(10) Ceramic industry. Mica has a lower melting temperature, which can lower the firing temperature of the ceramic body. The hardness of mica is also lower than that of quartz and feldspar. It consumes less energy during crushing and grinding of raw materials. In addition, it is compatible with the glaze and strengthens the link between the blank and glaze, improve product quality.
(11) Daily necessities and cosmetics. Mica has elasticity, suitable gloss and high whiteness, and can be used as a cosmetic to prevent skin tanning. In addition, Canada and South Africa use mica components containing TiO2 to make light toothpastes, which have obvious protective effects on teeth.
(12) Paper industry. Mica can also be used as a filler in the paper industry. The paper with mica filler has a wide white color, strong reflection of ultraviolet rays, and is not easy to yellow when stored for a long time.
(13) Rubber industry. In the processing of rubber products, mica powder is a good lubricant and mold release agent; mica powder is also a rubber reinforcing agent such as styrene butadiene rubber (SBS) and so on. Filling with an appropriate amount of mica powder instead of white carbon black is useful for improving the quality of rubber products and reducing production costs.
