Powder coating is a completely different form from general coatings, existing in the form of fine powder. Due to the absence of solvents, it is called powder coating. The main characteristics of powder coatings are: harmless, efficient, resource-saving, and environmentally friendly. It has two main categories: thermoplastic powder coatings and thermosetting powder coatings.

Simply put, thermosetting refers to a coating that can be cured and crosslinked by heating. The crosslinked coating is non melting and insoluble, and there is a chemical reaction during the heating process. Thermoplasticity refers to the softening of powders after heating, but without cross-linking, with only physical changes and no chemical reactions during the heating process. The specific performance differences are as follows.

Thermoplastic powder coating

Thermoplastic powder coating. Thermoplastic powder coatings began to appear in 1950. They melt at the spraying temperature and solidify into a film when cooled. Due to the simple processing and spraying methods, powder coatings only require heating, melting, leveling, cooling, or extraction solidification to form a film, without the need for complex curing equipment. Most of the raw materials used are common polymers in the market, which can meet the performance requirements under most conditions. But there are also some shortcomings, such as high melting temperature, low coloring level, and poor adhesion to metal surfaces. However, commonly used thermoplastic powder coatings still exhibit some unique properties, among which polyolefin powder coatings have excellent solvent resistance; Polyvinylidene fluoride coating has outstanding weather resistance; Polyamide has excellent wear resistance; Polyvinyl chloride has a good price performance ratio; Thermoplastic polyester powder coating has the advantages of beautiful appearance and high artistic value. These characteristics make thermoplastic powder coatings occupy a large proportion in the coatings market.

Thermoplastic powder coating is composed of thermoplastic resin, pigment, filler, plasticizer, stabilizer and other components. Thermoplastic powder coatings include polyethylene, polypropylene, polyester, polyvinyl chloride, chlorinated polyether, polyamide, cellulose, and polyester.

Construction technology: Thermoplastic powder is commonly used for dip coating, commonly known as dip molding.

1.1 Polyvinyl chloride powder is one of the cheapest polymers for industrial large-scale production. It has excellent solvent resistance, good corrosion resistance to water and acid, impact resistance, salt spray resistance, can prevent food contamination, and has high insulation strength for electrostatic spraying. Mainly used for painting metal mesh panels, steel furniture, chemical equipment, etc.

1.2 Polyethylene powder coating has excellent corrosion resistance, chemical resistance, excellent electrical insulation, and UV radiation resistance. The disadvantage is that the mechanical strength is not high and the adhesion to the substrate is poor. Can be used for chemical tanks, impellers, pumps, pipeline inner walls, instrument casings, metal sheets, refrigerator inner panels, automotive components, etc.

1.3 Nylon powder coating. Nylon, also known as polyamide, has a relatively high melting point due to the formation of hydrogen bonds between the nitrogen atoms of the chlorine group on the molecular chain and the hydrogen atoms on adjacent segments. Nylon has the advantages of high mechanical strength, impact resistance, hardness, wear resistance, low friction coefficient, and low dust absorption, and can be used for components with special requirements. Such as used for water pump impellers, textile machinery components, starting piston components for diesel engines, propeller impellers for sailboats, car wheels, motorcycle mounts, agricultural machinery, construction and sports equipment, etc. In addition, due to its salt water resistance and inertness to mold and bacteria, nylon is very suitable for manufacturing coatings immersed in or in contact with seawater. At the same time, nylon powder coatings are non-toxic, odorless, not corroded by mold, and do not promote bacterial growth. They are very suitable for spraying parts in the food industry, drinking water pipes, and food packaging.

1.4 Fluororesin powder coating. There are many types of fluorinated polymers that can be used to prepare powder coatings, such as polytetrafluoroethylene (PTFE), polytetrafluoroethylene (PTFCE), polyvinylidene fluoride (PVDF), etc. Polytetrafluoroethylene has a melting point of up to 327 ℃ and can be used for a long time in the range of -250 to 250 ℃. In addition, it has excellent corrosion resistance and does not corrode even in aqua regia. It has excellent dielectric properties, extremely low friction coefficient, and self-lubricating properties, so it is known as "PTFE"; Plastic King” It is called. Widely used in petroleum and chemical anti-corrosion coatings, sealing, bearing lubrication materials, electronic and electrical materials, ship launching guides, and non stick pot coatings. Polytrifluorochloroethylene is cheaper than PTFE, the processing temperature can be reduced, the coating can be used for a long time below 130 ℃, the ability to resist alkali and hydrogen fluoride corrosion is better than acid resistant enamel, and the ability to resist hydrochloric acid, dilute sulfuric acid, hydrogen chloride, and chlorine corrosion is better than stainless steel equipment. It has been widely used in anti-corrosion equipment for chemical plants, pesticide factories, pharmaceutical factories, detergent factories, etc. The biggest advantage of polyvinylidene fluoride powder coating is its excellent weather resistance. It has high degradation resistance when exposed to outdoor sunlight and does not absorb dust, making it easy to maintain its original luster. 5. Chlorinated polyether powder coating. Chlorinated polyether has excellent chemical stability, and its coating has good corrosion and dissolution resistance to various acids, bases, and solvents. Its chemical stability is second only to polytetrafluoroethylene, and its mechanical and friction properties are also very good. Chlorinated polyether powder coating is mainly used in chemical equipment, pipeline lining, instrument equipment shell, etc. Its disadvantage is poor adhesion to metals. Adding additives can improve the adhesion with metals.

1.5 Latex powder coating

Latex powder is made by drying lotion through spray, most of which are vinyl acetate copolymers. Coatings produced using latex powder are called latex powder coatings. On site mixing with clean water is currently the most environmentally friendly coating among wall coatings.

Thermosetting powder coating

Thermosetting powder coating refers to a hard coating made of thermosetting resin as a film-forming substance, which can form an insoluble and non melting texture after adding a crosslinking curing agent and heating. No matter how high the temperature is, the coating will not soften like thermoplastic coatings, but can only undergo decomposition. Due to the low polymerization degree and molecular weight of the resin used in thermosetting powder coatings, the coating has good leveling and decorative properties. Moreover, the low molecular weight prepolymer can form a network of cross-linked macromolecules after curing, resulting in good corrosion resistance and mechanical properties of the coating. Therefore, the development of thermosetting powder coatings is particularly rapid.

Thermosetting powder coatings are composed of thermosetting resins, curing agents, pigments, fillers, and additives. Thermosetting powder coatings include epoxy resin series, polyester series, and acrylic resin series.

Construction technology: Thermosetting powder coatings are mostly electrostatic spraying, commonly known as spray coating.

2.1 Epoxy powder coating. Due to its excellent adhesion to metals, corrosion resistance, hardness, flexibility, and impact strength, it is the first variety to be applied in thermosetting powder coatings. The formulation of epoxy powder coating is composed of epoxy resin, curing agent, pigment, filler, and other assistants. The contributions of these components to the performance of the formed powder coating are mutually constrained and influenced. A suitable formula is actually the result of the coordination of various components.

2.2 Polyester powder coating. Polyester powder coatings have unique properties compared to other types of powder coatings. It shows better weather resistance and UV light resistance than epoxy resin. In addition, due to the polar functional groups of polyester resin, its powder coating rate is higher than that of epoxy resin. It is less prone to yellowing during baking, has high glossiness, good leveling, full paint film, light color and other characteristics, making it highly decorative. Generally used in fields such as refrigerators, washing machines, vacuum cleaners, instrument casings, bicycles, furniture, etc.

2.3 Acrylic powder coating. Acrylic resin powder coatings have two types: thermoplastic and thermosetting. The biggest advantage of thermosetting acrylic resin powder coating is its excellent weather resistance, color retention, pollution resistance, strong metal adhesion, and excellent coating appearance, making it suitable as a decorative powder coating. Yongji Industrial Co., Ltd. is located in; Hometown of Chinese Coatings& mdash;— Shunde, Guangdong, covering an area of nearly 10000 square meters, is a high-tech outward oriented powder coating production enterprise that integrates research and development and operation.

The company was founded in 1997, and we have always adhered to the principle of 'riding'; User first, quality first; Our business philosophy is that in 2003, the company fully passed the ISO9001-2000 international quality management system certification. In 2004, it was evaluated by the National Quality Evaluation Center as; Chinese Quality Credit Enterprise;, The Yongji brand, built with high-quality products and excellent services, has won a good reputation among customers. In July 2018, the company underwent a comprehensive upgrade and passed the ISO9001:2015&ISO14001:2015 Quality&Environmental Management System certification.

Since its establishment, the company has maintained healthy, stable, and rapid growth. From two small production lines and a small factory with more than ten people in the early stages of construction, it has developed into a modern enterprise with an experienced and skilled technical and management team, with an annual output of over 15000 tons and annual sales exceeding 200 million yuan.