After decades of development, the coating materials used on coatings are no longer limited to polyurethane foam, etc. With the development of the silicone industry, silicone coatings, and inks have also developed rapidly. Silicone coatings have a wide range of applications in the coatings industry because of their unique properties, so what is silicone coating?
Conventional coating material is new polymer material consisting of a mixture of polymer substances and ingredients that can be coated on the surface of the substrate to form a continuous film with strong adhesion.
Silicone coating is a class of polymer collectively that silicon atoms and oxygen atoms alternately linked to form a skeleton, then different organic groups linked to the silicon atoms, is also an element of organic coatings, a silicone resin or modified silicone resin as the main film-forming material. Silicone coating can be widely used in the defense industry, electrical industry, and other industries.
Here's more information about it:
- How to classify silicone coatings?
- What are the advantages of silicone coating?
- How to use silicone coating?
- How to cure silicone coating?
- How to apply silicone coatings?
- How to make silicone coatings?
1. How to classify silicone coatings?
1.1 Classifying by coating film-forming material
(1) Pure silicone resin coatings
Pure silicone resin coatings have outstanding heat resistance and insulating properties, which show excellent weathering and corrosion resistance in higher temperature environments, and are also excellent high-temperature insulating coatings.
(2) Silicone-modified resin coatings
Silicone-modified resin coatings, including Silicone-modified Phenolic, Alkyd, Polyester, Acrylic, Epoxy, and Polyurethane resin, according to the amount of silicone materials can be improved to varying degrees of heat resistance, weathering, corrosion resistance, flexibility, and other properties, but also to improve the film-forming properties of silicone resins.
1.2 Classifying by coating application
(1) Silicone heat-resistant coating
Heat-resistant coatings are coatings that can withstand temperatures above 200℃ for a long time. Silicone heat-resistant coatings have excellent heat-resistant properties and are widely used in heat-resistant coatings, they often start to decompose at about 300 °C. The performance of silicone heat-resistant coatings is related to the methyl/phenyl value contained in the silicone oligomer used because the phenyl group has better heat resistance and poorer physical and mechanical properties than the methyl group.
XJY-83350 Polyester Modified Sheet Silicone Resin can make high-temperature-resistant powder coatings as well as liquid coatings. Silicone resin is characterized by its excellent heat resistance, excellent weather resistance, ozone resistance, arc resistance, hydrophobicity, moisture resistance, anti-salt spray, anti-mold, and other properties.
XJY-801 Polymethylsilsesquioxane ( Spherical Silicone Resin Powder) has improved lubricity, scratch resistance, dispersion, and hydrophobicity, which is suitable for high heat resistance and solvent resistance coatings and inks, with good toughness and scratch resistance. Compared with inorganic powders, it is easier to disperse, less likely to settle, and has better adhesion when combined with coatings. It has a particularly delicate touch and can form a more advanced surface coating.
(2) Silicone insulating coating
Silicone insulating coating is a very important class of insulating coatings, H-class insulating materials, the heat-resistant grade can up to 180 ℃. It has excellent thermo-oxidative stability and insulating properties, water and moisture resistance, a wide range of use, insulation resistance in a wide range of temperatures (-50℃-250 ℃), and can be used normally in the high and low-frequency range, in the destruction of high temperatures, generally will not burn, will not form char and conductive.
Silicone insulating coatings for a wide range of applications can be used as a high and low-temperature insulating paint, It can be used as high and low-temperature resistant insulating paint, silicone adhesive insulating paint, silicone-insulating impregnating paint, silicone-insulating coating, silicone insulating covering paint, silicone insulating paint for silicon steel sheet, silicone paint for electrical components, flame-retardant silicone insulating paint, silicone moisture-proof insulating paint, and so on.
XJY-8010/XJY-8250B Sheet Silicone Resin are silicone resins with light group functional groups, which are used in high-temperature-resistant powder coatings as well as liquid coatings. The first and foremost characteristic of silicone resin is its excellent heat-resistant property, which hardly decomposes under 200℃ or even higher temperatures, it can be used in the preparation of various heat-resistant paints, and its heat-resistant insulation grade can reach the H class.
(3) Silicone weathering coatings
Silicone weathering coatings generally use Alkyd, Polyester, and Acrylic resin-modified silicone resin, which is a class of the largest amount of weathering coatings, this type of paint in the outdoors can withstand a variety of natural changes. Alkyd-modified silicone resin weathering coatings life can be up to 8-10 years, which is inexpensive, can room temperature curing, has a wide range of applications, and can be used for outdoor facilities and equipment coating; Polyester and Acrylic modified silicone resin weathering coatings' curing agent is the melamine resin, often used in civil construction, waterproofing coatings for housing.
2. What are the advantages of silicone coating?
2.1 High-temperature resistance
Silicone resin has excellent heat resistance, silicone-modified resins contain more than 50% silicone and have significantly improved heat resistance. Mainly Si-O-Si as the skeleton, varnish can be used for a long time at 200℃ ~ 250 ℃ without decomposition or discoloration. At higher temperatures (such as 400 ℃ or more), Si atoms connected to the Alkyl decompose (or combust), forming new intermolecular Si-O-Si bonds and Si-O-M bonds, rather than decomposing the resin.
Silicone coating has good high-temperature insulation, it can meet spacecraft, aircraft, electronic and electrical appliances, and other industrial sectors' requirements that electronic components temperature use is increasing.
Silicone insulating coatings can use silicone resin, silicone-modified epoxy resin, or silicone-modified polyester for the film-forming material, there are two types, varnish and enamel, both high-temperature curing type and low-temperature curing type. Silicone insulating coatings can make the motor operate at temperatures up to 180 ℃ and can be operated at high-temperature conditions, it has a wide range of use, in a wide range of frequencies, and its individual electrical constants and dielectric loss are very small with the small temperature change, and its electrical performance is not only at high temperatures, but also at low temperatures are better than other organic coatings. Another characteristic is that when it is damaged at high temperatures, it generally does not burn and does not form cokes and conductive phenomenon.
Silicone-modified Alkyd, Polyester, Polyacrylate, and other coatings ' weathering significantly improved and can be used for outdoor long-lasting, highly decorative protective coatings, such as silicone roof coating. Silicone-modified Alkyd resin coatings, not only maintain the original air-drying characteristics, and weatherability can be greatly improved. Silicone-modified Polyurethane coatings are widely used for aircraft skins, large storage tank surfaces, architectural roofing, and protection of cultural relics. Silicone-modified Acrylic resin coatings have excellent weather resistance, light, and color performance is good, not easy to chalk, have good gloss, widely used in internal and external decoration of buildings.
Silicone coatings have very low surface tension and excellent waterproof performance, coupled with superior cold resistance, heat resistance, elasticity, and weatherability, so silicones coating are widely used in waterproof, moisture-proof coatings on building.
3. How to use silicone coating?
(1) Manual spraying:
It can be sprayed by aerosol cans or hand-held spray guns and is usually used for small-batch production. This method is more time-consuming than automatic spraying equipment and requires a higher level of spraying personnel, with slightly less stability between spraying batches.
(2) Selective spraying:
This is an automated spraying process that uses a programmable spray path to spray silicone coatings onto specific areas of the board. The process is suitable for high-volume production and can reduce the need for masking. The selective spraying process requires high surface drying time and viscosity of the coating, and the process parameters need to be adjusted and figured out.
The board is dipped into the silicone coating and then removed. The impregnation thickness depends on the impregnation speed, removal speed, impregnation time, and viscosity. It can also be used for mass production. Dipping is only possible if both sides of the board need to be coated and the areas that do not need to be coated need to be masked.
(4) Brush coating:
It is a simple application method, generally used mainly for small batch production or for repairs and rework. Simply brush the coating evenly onto the substrate.
4. How to cure silicone coating?
Silicone coating generally follows a moisture-curing mechanism. The silicone material reacts with moisture in the environment to form a cured coating. The initial moisture-curing process is usually accompanied by evaporation of the solvent. As the carrier solvent evaporates, the moisture reacts with the silicone material to begin the curing process. During PCB coating, the moisture in the air initiates a polymer chain reaction that converts wet polymers (lower molecular weight polymer molecules) into solid polymers (larger molecular weight polymer macromolecules). Curing and drying occur simultaneously. Heating can accelerate the curing speed of silicone coatings, but be careful to ensure that air bubbles have been completely eliminated before heating the coating, otherwise, it is necessary to extend the coating at room temperature conditions of the resting time.
5. How to apply silicone coatings?
(1) Construction field
Silicone coatings are mainly used for exterior wall coatings, silicone roof coating systems, and floor coatings in the construction field. Because of its excellent heat resistance, weather resistance, chemical corrosion resistance， and other characteristics, silicone coating is more and more widely used in the construction field, especially in silicone roof coatings. For example, a silicone roof coatings system is a very effective solution when the existing roof is a little older. Silicone roof coatings can protect the entire roof surface in harsh environments such as high temperatures and high humidity, silicone roof coatings also improve the gloss and roof life of the building surface. The silicone roof coating systems are suitable for new spray polyurethane foam, EPDM, TPO, aged PVC, aged acrylic coatings, concrete, asphalt built-up roofs, granulated modified bitumen roofs, and metal roofs.
(2) Automotive field
Silicone coatings in the automotive field are mainly used for automotive spraying and automotive parts surface coating. Silicone coatings have high hardness, excellent abrasion resistance, and chemical corrosion resistance, which can effectively protect the automobile surface from external erosion and improve the aesthetics and life of the automobile's smooth surface.
Silicone coatings are mainly used for coating and protecting electronic components in the electronic field. Silicone coatings can effectively prevent the surface of electronic components from chemical erosion, and improve their working life and reliability. In addition, silicone coatings are also widely used in the manufacture of liquid crystal displays, touch screens, and other electronic products.
(4) Other fields
Silicone coatings can also be used in aerospace, medical devices, food packaging, the chemical industry, and other fields. For example, silicone coatings can be applied to the exterior surface coating of aircraft, with wind erosion, heat insulation, and UV rays, it also can reduce static electricity and other functions.
In summary, silicone coatings have a wide range of applications, with the continuous improvement and refinement of related technologies. In the future, the development and prospects of silicone coatings are also very broad.
6. How to make silicone coatings?
Silicone coating is a kind of elemental organic coating that silicone resin or modified silicone resin as the main film-forming material. Silicone coating has the advantage of strong weather resistance, which can be able to resist UV rays, humidity, acid rain, and other bad weather conditions; good adhesion with the substrate can be closely attached to a variety of surfaces, including metal, plastic, stone, etc.; good corrosion resistance; stain resistance; easy construction and so on. How to make your products more competitive?
XJY Silicones is one of the leading silicone MQ resin and VMQ silicone manufacturers in China, with more than 30 years of R&D and manufacturing experience in the silicone industry as well as more than 15 related patents and technical support. Our silicone MQ resin raw material products can meet the needs of silicone coatings and support the provision of diversified customized solutions.