Coating knowledge: powder coating type

Core tip: Although there are not as many kinds of powder coating as solvent coating, there are also many polymer resins that can be used as powder coating Generally, it can be divided into thermosetting type and thermoplastic type 1 Thermosetting powder coating refers to a kind of hard coating which can not be dissolved or melted after heating with thermosetting resin as film-forming substance and curing agent for crosslinking reaction No matter how high the temperature is, the coating will not soften like the thermoplastic coating, but will only decompose Because the resin used in thermosetting powder coating is prepolymer with low polymerization degree and low molecular weight, the coating has good leveling property, good decoration and low molecular weight prepolymer Paint knowledge | precautions for wall paint color selection Recommended introduction: when painting the wall, the owner sometimes has difficulty in choosing what color of the wall paint to paint In fact, there is no ugly color in the wall paint, only the disharmonious color matching The use of wall color contains the knowledge of health Too strong color will stimulate people's perception, make people have a sense of fidgety, affect people's mental health Grasp the basic principles of wall color and paint a colorful space 1、 Wall paint color selection notice 1 Light color is generally used for the top surface Light colors make people feel light, dark colors make people feel heavy Usually, the treatment of rooms is from top to bottom, from shallow to deep For example, the ceiling and walls of rooms are white and Coating home news: Although the variety of powder coating is not as wide as solvent coating, but can be used as powder coating polymer resin is also many Generally, it can be divided into thermosetting type and thermoplastic type 1 Thermosetting powder coating refers to a kind of hard coating which can not be dissolved or melted after heating with thermosetting resin as film-forming substance and curing agent for crosslinking reaction No matter how high the temperature is, the coating will not soften like the thermoplastic coating, but will only decompose The resin used in thermosetting powder coating is prepolymer with low polymerization degree and low molecular weight, so the coating has good leveling property and good decoration Moreover, the prepolymer with low molecular weight can form network crosslinked macromolecule after curing, so the coating has better anticorrosion and mechanical properties Therefore, thermosetting powder coating develops rapidly 1.1 epoxy powder coating Because of its excellent adhesion to metal, corrosion resistance, hardness, flexibility and impact strength, it is the first type of thermosetting powder coating to be used The preparation of epoxy powder coating is composed of epoxy resin, curing agent, pigment, filler and other assistant The contribution of these components to the properties of the powder coating is mutual restriction and influence A suitable formula is actually the result of coordination of various components 1.2 polyester powder coating Compared with other types of powder coating, polyester powder coating has unique properties It is better than epoxy resin in weather resistance and UV light rotation resistance In addition, due to the polar group of polyester resin, the powder loading rate is higher than that of epoxy resin, which is not easy to turn yellow in the baking process, with high glossiness, good leveling, full film, light color and other characteristics, so it has good decorative properties Generally used in refrigerator, washing machine, vacuum cleaner, instrument shell, bicycle, furniture and other fields 1.3 acrylate powder coating There are two kinds of acrylic resin powder coatings: thermoplastic and thermosetting The biggest advantage of thermosetting acrylic resin powder coating is that it has excellent weather resistance, color retention, pollution resistance, strong metal adhesion, excellent film appearance, and is suitable for decorative powder coating 2 Thermoplastic powder coating Thermoplastic powder coating began to appear in 1950 It melts at spraying temperature and solidifies into film when it cools Because of the simple processing and spraying method, the powder coating only needs to be heated, melted, leveled, cooled or extracted and solidified to form a film, without complex curing device Most of the raw materials used are common polymers on the market, which can meet the requirements of service performance under most conditions But there are also some shortcomings, such as high melting temperature, low coloring level, poor adhesion with the metal surface and so on However, the commonly used thermoplastic powder coating still shows some special properties, among which polyolefin powder coating has excellent solvent resistance; polyvinylidene fluoride coating has outstanding weather resistance; polyamide has excellent wear resistance; PVC has good price / performance ratio; thermoplastic polyester powder coating has beautiful appearance and high artistic quality These characteristics make the thermoplastic powder coating occupy a large proportion in the coating market 2.1 PVC powder is one of the cheapest polymers in large-scale industrial production It has excellent solvent resistance, good corrosion resistance to water and acid, impact resistance, salt spray resistance, can prevent food pollution and high insulation strength to electrostatic spraying Mainly used for coating metal mesh, steel furniture, chemical equipment, etc 2.2 polyethylene powder coating has excellent corrosion resistance, chemical resistance, excellent electrical insulation and UV radiation resistance The disadvantages are low mechanical strength and poor adhesion to the matrix It can be used in chemical tank, impeller, pump, inner wall of pipeline, instrument shell, metal plate, inner net plate of refrigerator, auto parts, etc 2.3 nylon powder coating Nylon (nylon) is also called polyamide, because the N atom of chlorine group on the molecular chain and the hydrogen atom on the adjacent chain segment are easy to form hydrogen bond, so the melting point of polyamide resin is generally high Nylon has the advantages of high mechanical strength, impact resistance, hardness, wear resistance, small friction coefficient, low dust absorption, etc it can be used for the parts with special requirements Such as pump impeller, textile machinery parts, diesel engine starting piston parts, sailboat propeller impeller, automobile wheel, motorcycle bracket, agricultural machinery, construction and sports equipment, etc In addition, due to its salt resistance and inertia to mould and bacteria, nylon powder coating is very suitable for making coating immersed in or contacting with seawater Meanwhile, nylon powder coating is non-toxic, tasteless, not eroded by mould, and will not promote bacterial growth It is very suitable for spraying parts of food industry, drinking water pipe and food packaging, etc 2.4 fluororesin powder coating There are many kinds of fluoropolymer powder coatings, such as polytetrafluoroethylene (PTFE), polytetrafluoroethylene (ptfce), polyvinylidene fluoride (PVDF), etc Polytetrafluoroethylene has a melting point as high as 327 ℃, which can be used for a long time in the range of - 250-250 ℃ In addition, it has excellent corrosion resistance, even in aqua regia, excellent dielectric properties, extremely low friction coefficient and self-lubricating property, so it is known as the "king of plastics" It is widely used in anticorrosive coating, sealing, bearing lubricating material, electronic and electrical material, ship launching guide rail and non stick pot coating, etc Polytetrafluoroethylene chloride is cheaper than PTFE, and its processing temperature can be reduced The coating can be used for a long time under 130 ℃ Its resistance to alkali and hydrogen fluoride corrosion is better than that of acid enamel, hydrochloric acid, dilute sulfuric acid, hydrogen chloride and chlorine corrosion is better than that of stainless steel equipment It has been widely used in chemical plant, pesticide plant, pharmaceutical plant, detergent plant and other anti-corrosion equipment The biggest advantage of PVDF powder coating is excellent weather resistance, high degradation resistance in outdoor exposure, and no dust absorption, it is easy to maintain the original luster 5 chlorinated polyether powder coating Chlorinated polyether has excellent chemical stability The coating has good corrosion resistance and dissolution resistance to a variety of 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 with metal The adhesion with metal can be improved by adding additives 2.5 latex powder coating latex powder is prepared by spray drying, and most of them are vinyl acetate copolymers The coating produced by emulsion powder is called emulsion powder coating At present, it is the most environmentally friendly coating in the wall coating Home of coatings is specialized in coatings, diatom mud, paint coating, coating technology, fire retardant coating news and coating, diatom mud, paint coating, coating technology, fire retardant coating decoration knowledge and decoration renderings,