Antibacterial Materials:
Utilizing the large specific surface area, multi-mesoporous structure, super-strong adsorption capacity and unique physical and chemical properties of nano-SiO₂, functional ions such as silver ions are uniformly designed into the mesopores on the surface of nano-SiOₓ and stabilized. Nano antibacterial powder (particle size only about 70 nm) with high efficiency, durability, high temperature resistance and broad-spectrum antibacterial activity has been successfully developed, which not only fills the domestic gap, but also the main technical indicators have reached or exceeded similar products in Japan. Tests show that when the concentration of nano antibacterial powder in water is only 0.315%, the antibacterial ability against representative Gram-positive and Gram-negative bacteria is very obvious, with an inhibition zone of 2-3mm. And as the concentration of nano antibacterial powder in water increases, the inhibition zone increases significantly. It is determined that when the content of Ag⁺ in water is 0.01mg/L, it can completely kill Escherichia coli in water and maintain no new bacterial colonies for up to 90 days.
The nano antibacterial powder is applied to enamel glaze to produce drum washing machines with mildew-proof and antibacterial functions, with an antibacterial rate of over 99%. It should be noted that the application conditions of nano antibacterial powder in enamel glaze are harsh. It must maintain strong antibacterial performance after being fired in a strongly alkaline liquid and at high temperature (about 900℃), which is unmatched by other antibacterial powders.
Adding nano antibacterial powder to interior wall coatings to produce interior wall coatings with long-term antibacterial and mildew-proof functions.
Applying nano antibacterial powder to women's underwear detergent, wool cashmere detergent, dish soap and hand sanitizer, the antibacterial performance is very significant as tested by the health and epidemic prevention department.
It can be predicted that with the enhancement of people's health awareness, nano antibacterial powder will be gradually accepted by relevant enterprises and the public, and stand out in industries such as bills, medical and health care, chemical building materials, home appliances, functional fibers and plastic products.
Other Applications
1. Applications in the Optical Field
Nano-particles are mainly used in infrared reflective materials in the form of thin films and multilayer films. Film materials made of nano-particles have good application prospects in the lamp industry. High-pressure sodium lamps and various iodine arc lamps for photography require strong lighting. However, 69% of the energy is converted into infrared rays after the filament is heated, indicating that a considerable amount of electrical energy is consumed as heat, and only a small part is converted into light energy for lighting. At the same time, the heating of the lamp tube will affect the service life of the lamp. How to improve luminous efficiency and increase illumination has always been a key problem to be solved urgently. The birth of nano-particles provides a new way to solve this problem. Since the 1980s, researchers have used nano-SiOₓ and nano-TiO₂ particles to make multilayer interference films with a total thickness of micron level, which are lined on the inner wall of the lamp cover. As a result, it not only has good light transmittance, but also has strong infrared reflection ability. According to expert calculations, under the same light brightness, this kind of lamp can save 15% of electric energy compared with traditional halogen lamps.
2. New Type of Plexiglass Additive
Plexiglass (PMMA) is commonly used for aircraft window materials. When the aircraft flies at high altitude, the window material is easily aged by ultraviolet radiation, resulting in reduced transparency. To solve this problem, using the strong ultraviolet reflection performance of nano-SiOₓ, surface-modified nano-SiOₓ is added in the production process of plexiglass. The produced product has more than doubled ultraviolet radiation resistance and 80% higher impact strength.