Why add green silicon carbide powder to improve the wear resistance of PET board coating?

Why add green silicon carbide powder to improve the wear resistance of PET board coating?
The addition of green silicon carbide powder (SiC) to PET board coating is mainly based on the multiple strengthening mechanisms of its unique physical and chemical properties on the wear resistance of the coating. The following is an analysis of the core reasons:
1. Micro-toughening and hardness improvement
‌Ultra-high hardness support‌
The Mohs hardness of green silicon carbide reaches 9.4 (second only to diamond), and its powder particles form a rigid skeleton in the PET coating. When the coating is rubbed by external force, these hard particles can effectively resist scratching and invasion, reduce the plastic deformation of the coating, and significantly delay the wear process‌. For example, on the surface of furniture that is frequently contacted, the scratch generation rate can be reduced by more than 30%.
‌Self-sharpening maintains cutting ability‌
Green silicon carbide crystals are anisotropic, and new sharp edges (self-sharpening) will be continuously exposed during wear, rather than passivation and shedding. This allows the coating to maintain high cutting efficiency for a long time and avoid wear resistance attenuation caused by abrasive loss‌
2. Coating structure strengthening effect
‌Densification filling and stress dispersion‌
The particle size of green silicon carbide powder is controllable (usually micrometer level), and it can be evenly dispersed in the resin matrix to fill the gaps between polymer molecular chains and reduce the porosity of the coating. At the same time, it can block the crack propagation path, disperse local stress, and improve the overall toughness of the coating. For example, in the wear resistance test of PET sheet, the wear amount of the coating with 20% green silicon carbide powder is reduced by about 40%.
‌Enhanced interface bonding stability‌
The surface of green silicon carbide is rich in silanol (-Si-OH), which can form hydrogen bonds or covalent bonds with the ester group of PET resin to reduce interface defects. Experiments show that the peel strength of the modified coating is increased by 25%, avoiding particle shedding caused by interface peeling.
3. Weather resistance and environmental corrosion resistance optimization
‌High temperature stability guarantee‌
The melting point of green silicon carbide is as high as 2250°C, and the thermal conductivity is 120W/(m·K). When the PET coating encounters local high temperature (such as heat generated by sunlight or friction), the heat can be quickly dissipated to prevent the resin from softening and causing a sudden drop in wear resistance. Car hood coating tests show that the heat deformation temperature of the coating containing green silicon carbide is increased by about 50°C.
‌Chemical inertness to resist corrosion and wear ‌ ‌ Its high stability to acids, alkalis and organic solvents (corrosion resistance > 99.5%) can prevent the coating from swelling or degradation in complex environments. For example, when the PET board of the kitchen countertop comes into contact with oily detergents, the wear life of the green silicon carbide modified coating is extended by more than 2 times ‌ ‌.
4. Functional synergistic gain ‌ ‌Friction coefficient regulation ‌ ‌ The nearly spherical structure of green silicon carbide micropowder can reduce the dynamic friction coefficient of the coating (from 0.8 to 0.3 level) and reduce sliding friction damage. It is suitable for scenes that require frequent mechanical contact, such as sliding door panels ‌ ‌. ‌Anti-slip and surface texture optimization‌
The rough particle surface enhances the static friction of the coating (the anti-slip coefficient is increased by 15%-30%), and the particle size ratio can achieve a multi-level texture from matte to satin.
Conclusion: The irreplaceable nature of green silicon carbide micropowder
Compared with traditional hardening materials (such as silica or aluminum oxide), green silicon carbide achieves a balance of triple performance of hardness-toughness-thermal stability:
‌Economical‌: Adding 5%-15% can significantly improve wear resistance and reduce the amount of high-cost resin‌;
‌Adaptability‌: Compatible with mainstream PET coating processes such as UV curing and epoxy modification, without the need to modify the production line‌;
‌Environmental protection‌: The inorganic component complies with the RoHS standard and avoids the risk of VOC release of organic wear-resistant additives‌.
Therefore, it has become a core additive to improve wear life in high-end PET sheets (such as medical equipment panels and elevator interior panels)‌