Application of Grim Mica powder in silicone high temperature resistant paint

High-temperature paint refers to paint that can withstand temperatures above 200℃ (can withstand 300~500℃ or higher in the short term). Made of heat-resistant resin (such as silicone, etc.), heat-resistant pigments and fillers (such as mica powder, etc.). After painting and drying, it can withstand high temperatures and will not cause significant discoloration or cracking and falling off. It is usually used to apply heating equipment, boiler shells, chimneys, heat exchangers, military industry, etc.

Steel is easily oxidized by air at high temperatures. If the low-carbon steel sheet is heated to 870℃ for 15 hours in the air, its mass will be reduced by 80%, and even disappear eventually. This is the corrosion phenomenon caused by the invasion of other substances in the air. In order to prevent this phenomenon from happening, heat-resistant paint came into being. The so-called heat-resistant paint is coated on the surface of high-temperature metal. In addition to having a certain decorative effect, it can make the metal become unoxidized and corrosion for a long time under high temperatures. In addition, it also has anti-rust, anti-bonding, insulation and anti-pollution. The heat-resistant paint is generally above 200℃, the paint film does not change color or fall off, and can still maintain certain physical and mechanical properties.

Components and properties of silicone heat-resistant coatings

(1) Resin. Silicone resin is the base material for silicone heat-resistant coatings, which directly affects the performance of heat-resistant coatings. Silicone resins are divided into pure silicone resin and modified silicone resin.

(2) Pigments and fillers. The pigments and fillers used in heat-resistant coatings must not only have the role in ordinary coatings, but also have heat resistance, that is, they do not destroy, discolor, do not affect the thermal stability of the resin and reduce the anti-aging properties of the resin under high temperatures. Commonly used are inorganic pigments and fillers (mica powder, etc.).

The heat resistance of pure heat-resistant resins is limited, and adding appropriate heat-resistant fillers (mica powder, etc.) can greatly improve their heat resistance. After adding pigment to silicone resin coating, its resistance is greatly improved and its heat resistance is greatly improved. The reason is that the organic groups on the side chain of silicone resin decompose within the range of 300 to 500°C. The organic group disappears completely and converts into an inorganic coating. Among them, the decomposed product SiO2 and part of Al are fused to form a Si—O—Al glass-shaped silicate inorganic compound coating, which has strong adhesion to the bottom layer, tough and wear-resistant, high temperature resistant, and still has excellent protective effects.

The chemical formula of mica crystal is: K0.5-1 (Al, Fe, Mg)2(SiAl)4O10 (OH) 2·nH2O, a complex silicon oxygen layer composed of two layers of silicon oxygen tetrahedrons and a layer of aluminum oxygen octahedrons. It can be split into extremely thin sheets, with a large diameter and thickness ratio, elastic and bendable. It also has significant characteristics such as acid resistance, alkali resistance, salt spray resistance, high temperature resistance (above 600℃), electrical insulation, and good wear resistance.

Performance advantages of mica powder in silicone high temperature resistant paint:

Unique high temperature resistance: high temperature resistance can reach up to 600 degrees;

Excellent chemical inertia: Improve corrosion resistance of neutral salt spray, acid, alkali and other corrosion resistance

Unique sheet structure: adjust the internal stress of the coating, improve the continuity, density and excellent mechanical properties of the paint film, and improve impact resistance;

UV shielding function: improves the weather resistance of the paint film, makes the paint surface color as new as new, and extends the service life of the substrate;

Application suggestions:

Application of Grea GA series/GB series in silicone high temperature resistant paint

Addition: 8%-15%;

Typical features: high temperature resistance can be up to 600 degrees; inert high temperature resistance filler, improve corrosion resistance of neutral salt spray, acid, alkali, oil and stains, etc.; sheet-like structure, adjust the internal stress of the coating, improve the continuity, density and excellent mechanical properties of the paint film, improve the impact strength; improve the weather resistance of the paint film, make the paint surface color as new as new, and extend the service life of the substrate.