Coating knowledge: new coating knowledge: Research Progress of new coating

Core tip: Zhang Wenyu (Luoyang Institute of ship materials, Luoyang, Henan 471039) Abstract: the types, research status and development trend of antifouling coatings, absorbing coatings, nano stealth coatings, automobile coatings, antiskid coatings and other new coatings for ships are described Key words: antifouling coating; absorbing coating; nano stealth coating; automobile coating; antiskid coating The phenomenon that microorganisms, plants and animals in the ocean attach to ships and have adverse effects on them is called fouling The fouling will not only increase the self weight and reduce the load weight of the ship, but also greatly increase the ship Paint agent, top 10 Chinese wall paint brands Recommended introduction: interior wall paint and exterior wall paint can achieve beautiful, clean and pleasant effects, but the effects in different environments are different, so the color of the paint will be different There are ten brands of Chinese paint, ten brands of global paint, ten brands of Chinese wall paint, and ten brands of Chinese paint, Famous trademark of Chinese paint and coating In private rooms, most of us choose according to our own personality, personal hobbies and living habits The younger generation will choose the interior wall paint with rich colors and bright colors, while the older ones will have some working experience Home of coatings: Zhang Wenyu (Luoyang Research Institute of marine materials, Luoyang, Henan 471039) Abstract: the types, research status and development trend of antifouling coatings, absorbing coatings, nano stealth coatings, automotive coatings, antiskid coatings and other new coatings for ships are described Key words: antifouling coating; absorbing coating; nano stealth coating; automobile coating; antiskid coating Fouling will not only increase the self weight and reduce the load weight of the ship, but also greatly increase the resistance of the ship, resulting in the decrease of ship speed and the increase of fuel consumption The most effective way to prevent marine biological pollution is to use antifouling coating It can be predicted that a series of environmental friendly coatings and advanced electrochemical methods will be applied and popularized in the near future Because of its simple construction, strong adaptability to the shape of the target and small impact on the maneuvering firepower performance of the weapon system, the absorbing coating has been paid more attention by many countries Nano material is the ideal "black body" in physics Nano stealth coating is the combination of nano technology and stealth coating It is an excellent electromagnetic wave absorbing material It can not only absorb radar wave, but also absorb visible light and infrared light With the continuous development of nanotechnology, nano stealth coating will have a broad application value and prospect Among many kinds of coatings, automobile coatings have become one of the representative varieties with the highest technical content and added value in the industrial coatings due to their ultra-high requirements for coating performance and unique coating process, which reflects the technical development level of a national coating industry This paper mainly describes the current situation and application of new coatings, such as marine coatings, absorbing coatings, nano stealth coatings and automobile coatings In the historical process of using all kinds of ships to explore the unknown world and develop and utilize the ocean, marine coatings have been faced with the problems of serious corrosion of the environment and the prevention and removal of marine attached organisms Among many anti fouling and anti rust methods, the most convenient and economical method is to use anti fouling and anti rust coatings 2.1 the main types of antifouling coatings for ships are as follows: ① self polishing antifouling coatings without organic tin; ② abrasive antifouling coatings in Wuxi; ③ non-toxic antifouling coatings (low surface energy coatings, biological antifouling coatings); ④ conductive antifouling coatings Among them, the main research and development goal is low toxic or non-toxic antifouling coating without organic tin, and the development of Wuxi self polishing or abrasive antifouling coating products is the fastest Wuxi self polishing antifouling coating has the characteristics of long-term antifouling, resistance reduction and energy saving, and meets the requirements of environmental protection, which is of great practical significance both economically and militarily Low surface energy antifouling coating is commonly known as "non stick" coating It uses the physical properties of low surface energy on the coating surface to make it difficult for marine organisms to adhere or even if the adhesion force is very small When the ship is sailing at low speed, it is easy to be removed by the shear force of sea water The existing low surface energy antifouling coatings are mainly based on organosilicon and organofluorine resin, which are made of organosilicon and organofluorine This kind of antifouling coating has been applied in practice, and the antifouling period is up to 5 years The natural antifouling agent for biological antifouling coating is a kind of natural antifouling substance extracted from a variety of marine animals and plants and land plants by biotechnology, which mainly includes the antifouling agent of macrophylla, the antifouling agent of kudong tree, the antifouling agent of acylated Salvia edulis, the antifouling agent of horseradish, the antifouling agent of sponge fatty acid, the antifouling agent containing protease, etc Bionic antifouling coating uses bionic principle There are two main directions: ① extracting natural active substances from the ocean as antifouling agents; ② simulating the skin structure of large marine animals to achieve antifouling Biotechnology is a high-output industry Using biotechnology to produce the above-mentioned antifouling agents is harmless to human body, environment and marine organisms Developing this field will produce huge social and economic benefits The conductive antifouling coating is to apply several layers of conductive coating on the hull surface When the micro direct current is applied on the surface of the conductive coating, the sodium hypochlorite will be produced by the electrolysis of seawater, so as to prevent the marine organisms from adhering to the hull surface There are three ways to realize low VOC antifouling coating: ① water-based antifouling coating; ② powder antifouling coating; ③ high solid content antifouling coating At present, the research and development of low VOC antifouling coatings at home and abroad are only the achievements in water-based antifouling coatings Marine antifouling coating is one of the most important marine coatings, which directly affects the interests of shipowners and the marine environment Therefore, researchers and coating suppliers strive to develop more environmentally friendly, better performance and more competitive marine antifouling coating The antifouling technology also includes electrochemical antifouling method, a new method of controlling corrosive microorganism Electrochemical Sterilization and external potential antifouling method 2.2 at present, the varieties of ship bottom antirust coating can be divided into three categories: ① traditional asphalt system and oily system; ② high-performance ship bottom antirust coating with epoxy, ethylene, epoxy asphalt, ethylene asphalt and chlorinated rubber resin as the main body; ③ new high-performance ship bottom antirust coating, mainly including modified epoxy and glass Scale coating, fluororesin coating, etc 2.3 special functional coatings for ships special coating materials for ships are an indispensable part of ship equipment It covers the following fields: high temperature resistance and heat insulation , fire protection, sound absorption damping, wave absorption, optical camouflage, etc., mainly including radar absorbing camouflage coating, absorbing sonar wave coating, infrared camouflage coating, heat radiation resistant coating, anti-skid coating for flight deck, high temperature resistant coating, etc., although the amount is not large, but the indispensable and alternative supporting materials for ships, and with the acceleration of modernization of weapons and equipment, special coating materials Material plays a more and more important role in all parts of the ship Absorbing coating absorbing coating is a kind of material which can absorb the electromagnetic wave energy projected on its surface and transform it into heat energy through material loss The absorbing coating is mainly composed of absorbent and adhesive Among them, the absorbent with specific electromagnetic parameters is the key to the absorbing coating, which determines the absorbing performance of the absorbing coating; the binder is the film-forming material of the coating, which makes the coating firmly adhere to the surface of the coating and form a continuous film According to different absorbents, absorbing coatings can be divided into the following categories: ferrite absorbing coatings, carbonyl iron absorbing coatings, metal ultrafine powder or metal oxide magnetic ultrafine powder absorbing coatings, ceramics Absorbing coating, nano absorbing coating, radioisotope absorbing coating, conductive polymer absorbing coating, retinyl Schiff base salt absorbing coating, chiral absorbing coating, doped high loss absorbing coating, rare earth element absorbing coating In order to widen the effective frequency band and realize the multi spectrum stealth effect, the main direction of the development of high-performance and wide-band absorbing coatings is to study At the same time, various new absorbents are studied and new absorbing mechanism is discussed to meet the target of "thin, light, wide and strong" Microwave absorbing coating is one of the main stealth materials in military, and it is used in civil The products are also widely used, such as human body safety protection, microwave darkroom elimination equipment and electromagnetic interference of communication and navigation system, safety information confidentiality, improvement of overall performance, improvement of signal-to-noise ratio, electromagnetic compatibility, electromagnetic radiation protection of waveguide or coaxial absorption elements, radio and television transmitting stations, industry Scientific and medical equipment electromagnetic radiation protection, daily necessities microwave oven, mobile phone electromagnetic radiation protection and many other aspects Nano stealth coating is a kind of stealth material fixed on the structure of weapon system According to its functions, it can be divided into radar stealth coating, infrared stealth coating, visible stealth coating, laser stealth coating, sonar stealth coating and multi-functional stealth coating Nano coatings are generally composed of nano materials and organic coatings, which should be called nano composite coatings more scientifically After decades of development, stealth coating, as one of the key technologies of stealth technology, has not only been used in flight missiles and other aircrafts, but also has been applied to naval ships, stealth armored vehicles, stealth mines, stealth artillery, stealth tanks, stealth vehicles, stealth radar, stealth communications by several major industrialized countries and military powers System, stealthy engineering, stealthy fortification, stealthy robot, stealthy combat suit, infrared stealthy flare and other technical equipment The application fields of nano materials in marine coatings are as follows: ① absorbing radar wave coating ② Infrared camouflage coating for warship: the composite powder of nano alumina, iron oxide, silicon oxide and titanium oxide combined with polymer fiber has strong absorption performance for the middle infrared band, and this composite has strong absorption performance for the infrared detector in this band It has a good shielding effect, not only has the excellent characteristics of absorbing radar waves, but also has the good performance of absorbing and dissipating infrared rays, and has the obvious stealth function ③ Submarine camouflage coating: the key technology of submarine camouflage coating is the wet reflectivity and aging resistance of the coating It is one of the effective ways to reduce the wet reflectance of camouflage coating and improve the aging resistance of camouflage coating ④ Super weather resistant hull paint: nano titanium dioxide has the ability to absorb ultraviolet rays, which can improve the aging resistance of the paint They can be used as one of the main additives in the future ⑤ Anti mildew coating for Ship Cabin: nano titanium dioxide, nano zinc oxide and other nano materials can be used as non-toxic, antibacterial agents with wide range and excellent thermal stability It can make use of the antibacterial effect of nano materials to prepare a new type of high-efficiency anti bacteria and anti mildew material and coating in the cabin