LYRIN Silicon Nitride Nanocomposite Coatings

Polysilazane is an organic-inorganic hybrid polymer composed of nitrogen, silicon, and carbon elements with Si-N as the repeating main chain. Compared with most organic polymers, polysilazane has stronger thermal stability, mechanical and chemical stability, as well as higher hardness and adhesion. When it comes to the properties of polysilazane, we have to understand silicon and nitrogen. Nitrogen, the most abundant component in the air. Air, the "life gas" we breathe every day, is layered and covers the surface of the Earth, appearing transparent, colorless, and odorless. It is mainly composed of nitrogen, oxygen, rare gases (helium, neon, argon, krypton, xenon, radon), carbon dioxide, and other substances (such as water vapor, impurities, etc.). Among them, nitrogen accounts for more than 78%. Nitrogen was discovered by humans 250 years ago and exhibits inertness, so it was named "azo", which means "lifeless". Nitrogen is "immiscible with water" and exhibits hydrophobic properties, with only 0.02 volume of N2 dissolved in a single pool of water. This is why white clouds composed of water vapor in the sky are dispersed and difficult to gather together.

Although nitrogen is considered an inert element, it can also form some very active compounds. For example, polysilazane, a new type of foreign bottleneck polymer material, has high reactivity with polar compounds such as water and oxygen. Meanwhile, due to the chemical inertness of nitrogen, it is commonly used as a protective gas. To prevent certain objects from being oxidized by oxygen when exposed to air, for example, filling grain silos with nitrogen can prevent grain from moldy or sprouting, and ensure long-term storage; The fruits and pastries on supermarket shelves are packed with natural nitrogen gas inside the bulging packaging; Liquid ammonia can also be used as a deep refrigerant, as a direct refrigerant for rapid freezing of food. In recent years, the 3R food pre packaged dishes that have become popular throughout the country, most of which are produced in the central kitchens of formal large factories, have undergone rapid freezing with liquid nitrogen at -196 ℃ to lock freshness and form a layer of natural liquid nitrogen preservative on the surface of cooked dishes.

Silicon, located between metals and non metals on the periodic table, is a type of metal belonging to the carbon group. Elemental silicon exhibits hydrophobicity. Silicon, like carbon, has four hands - capable of forming four chemical bonds simultaneously. However, silicon usually only extends one arm and cannot extend both arms at the same time. As a chemical relationship that cannot form double bonds, silicon can participate in very few chemical reactions. So, silicon element exhibits inherent inertness, with chemical stability, oxidation stability, high temperature resistance, corrosion resistance, hydrophobicity, and good electrical insulation. And silicon has a high chemical affinity for oxygen, so it is difficult to see elemental silicon in nature. Elemental silicon (i.e. silicon chips) needs to be industrially purified, and it is always with other friends, one of whom is oxygen. Silicon always reacts with oxidation to form silicon dioxide (SiO2), which leads to many beautiful and interesting things happening. We see colorful agates, coastal sand, beautiful crystals, sparkling opals, peculiar turquoise, dense and hard flint, and so on in nature. The essence or composition of these things is silica. There are hundreds of variant names for mineral crystals composed of natural silica. In front of those who love jewelry, they can be amethyst, opal, beautiful agate, gray chalcedony, turquoise, etc.

It is precisely based on the various characteristics of nitrogen and silicon that endow the "bottleneck" material, polysilazane polymer, with excellent physical and chemical properties. It has the characteristics of high temperature resistance, oxidation resistance, corrosion resistance, insulation, heat insulation, waterproofing, anti graffiti, self-cleaning, low viscosity, low surface energy, solvent-free and super hardness, excellent adhesion to most substrates, hydrophobicity of water contact angle that naturally maintains above 95 ℃ for a long time, and ultra-thin varnish (usually in the range of tens of nanometers to several micrometers). The production of a "bottleneck" poly (silazane) resin nano modified transparent coating will be applied to hydrophobic, oil repellent, self-cleaning biomimetic coatings. We often see water droplets rolling and not dispersing on many plants such as lotus leaves in our daily lives. If we look at them under a microscope, the surface of lotus leaves has a layer of fluff and some tiny nanoscale wax particles, as shown in the picture above. These wax particles will repel the infiltration of water and condense it into water droplets. Similarly, if we fold a dandelion and immerse it in water, it will not stick to the water. This repulsive and water repellent phenomenon is hydrophobic, but has waterproof, oil resistant, and self-cleaning properties. If applied to metal, mahogany furniture, luxury leather goods, high-end bathroom, fabrics and other items such as machine tools, cars, kitchenware, other related materials can also be introduced to increase anti-corrosion, antibacterial and other properties. Our modern nano coating is based on this biomimetic principle.

Nanocoating is a thin film coating composed of nanoparticles, with a thickness typically ranging from a few nanometers to several tens of micrometers. These nanoparticles can be metals, ceramics, polymers, or other materials with special chemical, physical, or optical properties. Nano coatings are mainly solutions made of high molecular weight polymers. Due to their low surface energy, nano coatings have the characteristics of "non stick", which can prevent water, moisture, and dirt. Nano coatings can also be used as three hydrophobic coatings, hydrophobic, oleophobic, and solvent repellent. Superhydrophobic surfaces strictly refer to surfaces where water droplets have a contact angle greater than 150 ° and a rolling angle less than 10 °. However, the preparation method of superhydrophobic surfaces with water contact greater than 150 ° is not only complex and costly, but also the micro nano structure of the coating surface is easily destroyed, making it difficult to maintain superhydrophobicity during use. Therefore, the search for a stable superhydrophobic or water contact>120 ° hydrophobic surface coating and a simple and feasible preparation method for constructing this coating have practical value in promoting the application of hydrophobic, oleophobic, and self-cleaning coatings in actual production and life.

HUNAN TENGCAN LYRIN TECHNOLOGY Co., Ltd. and its Silicon New Materials Industry Research Institute team, based on the principle of lotus leaf nano biomimicry and nanotechnology application research, adhere to the concept of production scale and wide application. While retaining the excellent mechanical and chemical stability of the "neck" material organic polysilazane to the coating and good adhesion to the substrate, they introduce metal oxide nanomaterials with hydrophilicity, acid and alkali resistance and antibacterial properties to improve the hydrophobicity of the polysilazane resin, and form micro nano composite structures on the coating surface, greatly improving the hydrophobicity of the coating. Due to its main component being organic polysilazane nanoresin, which has characteristics such as low surface energy, high hydrophobicity, and low viscosity, a nano level protective film is formed on the surface of the substrate, which can be repeatedly sprayed and wiped, and the micro nano structure is more stable. This product is a "transparent nano resin maintenance liquid", divided into two specifications: industrial and civilian. Industrial use is a two-component solution that can directly add powder to increase concentration, while civilian use is a transparent maintenance liquid that can be directly applied. It can be widely used in daily maintenance of metals such as automobiles, kitchenware, rosewood furniture, luxury leather goods, high-end bath appliances, hydrophobic jackets, as well as stone surfaces, ceramic surfaces, electrical surfaces, etc. It can be easily manually applied as a surface maintenance product and has the characteristics of hydrophobicity, oleophobicity, anti fouling, anti fingerprint, self-cleaning, anti-corrosion, wear-resistant wiping, and gloss preservation. It can be repeatedly sprayed and then wiped clean by simply touching a towel with water. And it has a certain self-healing ability. If there are small scratches and light scratches, just pour some hot water, and the main resin components of nano modified materials will generate gel in situ when encountering hot water for self-healing, so that our life will be better!