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.
Fumed silica can improve the following properties of resin composites:
1. Improve strength and elongation:
Ring Oxygen resin is the basic resin material. Adding fumed silica (fumed silica) to epoxy resin is completely different in structure from the epoxy resin-based composite added with coarse crystalline silica (silica, etc.) Materials, coarse-crystalline silica is generally added as a reinforcing agent, and it is mainly distributed among the chains of polymer materials. However, nano-silica has the characteristics of severe lack of coordination on the surface, huge specific surface area, and lack of oxygen on the surface. It shows extremely strong activity and can easily bond with the oxygen of epoxy ring molecules, thereby improving the bonding force between molecules. At the same time, some nano-silica particles are still distributed in the gaps of the polymer chain. , compared with coarse-crystalline silica particles, it exhibits high ripple properties, thus greatly improving the strength, toughness, and ductility of the epoxy resin material added with fumed nanosilica (fumed white carbon black).
2. Improve the wear resistance and improve the surface finish of the material:
The nanoscale silica particles produced by the gas phase method are 100-1000 times smaller than ordinary silica. into epoxy resin to facilitate drawing into filaments. Due to the high fluidity and small size effect of fumed nanosilica, the surface of the material is denser and cleaner, and the friction coefficient is smaller. In addition, the high strength of the nanoparticles greatly enhances the wear resistance of the material.
3. Anti-aging performance:
A fatal weakness in the use of epoxy resin-based composite materials is the poor anti-aging performance. The main reason is the 280-400nm band of solar radiation. The medium and long wave effects of ultraviolet rays have a very serious destructive effect on resin-based composite materials. The degradation of polymer chains causes rapid aging of resin-based composite materials. Fumed nanosilica (fumed white carbon black) can strongly reflect ultraviolet rays. Adding it to epoxy resin can greatly reduce the degradation effect of ultraviolet rays on epoxy resin, thereby delaying the aging of the material.