It is understood that fumed silica (fumed white carbon black) is white granular and inactive in nature. It does not interact with halogens and halogenated substances other than fluorine and hydrogen fluoride. Through the action of hydrogen, sulfuric acid, nitric acid, and perchloric acid (except for hot concentrated phosphoric acid), the fumed silica particles are fully and evenly dispersed into the resin material, which can fully achieve the purpose of improving the properties of the resin-based material.
The particle size of fumed silica is very small, so it has a large specific surface area, strong surface adsorption, high surface energy, and is very easy to agglomerate. Fumed silica has high chemical purity and good dispersion properties. It also has specific properties in terms of thermal resistance and electrical resistance. With its superior stability, reinforcement, thickening and thixotropy, it is unique in many disciplines and fields. Characteristics play an irreplaceable role.
The application and modification of fumed silica in the plastics industry:
Utilize the high strength, high fluidity and small size of fumed silica The effect is to improve the toughness of the material without reducing the rigidity of the material, and at the same time improve the density, smoothness, wear resistance, rigidity and other capabilities of plastic products.
If through appropriate surface modification, the purpose of strengthening and toughening the plastic can be achieved at the same time. Adding fumed silica to polyethylene, through a special method, the silica can be evenly dispersed in the matrix to produce a polyethylene composite material with high wear resistance and high hardness.
Using fumed silica to transmit light and have small particle size, the plastic can become denser. Adding silica to the polystyrene plastic film not only improves its transparency, strength, toughness, but also makes it waterproof Performance and anti-aging properties are also significantly improved.
Adding fumed silica to epoxy resin can significantly improve its brittleness. It can overcome the defects of reduced material rigidity and strength caused by the toughening of elastomers, and achieve the purpose of strengthening and toughening. If nanosilica is modified by a coupling agent, its impact toughness can be increased by 124% and its tensile properties can be increased by 30%. In addition, the hardness, wear resistance, temperature resistance and insulation properties of the product can also be improved.
By modifying ordinary plastic polypropylene, the main technical indicators (water absorption, insulation resistance, compression residual deformation, flexural strength, etc.) have reached or exceeded the performance indicators of engineering plastic nylon 6, achieving polypropylene Propylene railway accessories can be used instead of nylon 6, and the product cost has dropped significantly.