Forty years of reform and opening up, China's infrastructure planning and construction have double growth, and the related engineering machinery, steel structure, coil and other industrial fields have also achieved rapid development. China's home appliance industry has established itself as the world's home appliance manufacturing base, and the number and types of home appliance production have grown rapidly. With the rapid development of infrastructure construction and home appliances, the demand for steel and the processing requirements of the surface are constantly improving. A thin coat coating can avoid corrosion of the steel surface in harsh environments.
Every year, the rust problem encountered in China will bring serious economic losses. The maintenance cost after rust is also very high. Some downstream areas cannot be returned to the factory for maintenance due to various reasons. Maintenance work is carried out under natural bare environment, for construction workers and Maintenance products are strictly tested.
Under the requirements of low cost, high economic efficiency and emphasizing the development of enterprise competitiveness, improving the anti-rust performance of coatings will prolong the maintenance period required in various fields and greatly save construction and product costs. Driven by the concept of “creating green and environmentally friendly new materials and solving the problem of environmentally friendly product conversion”, Guangzhou Linghao Technology Co., Ltd., through its own efforts, carries out product innovation according to market demand, and develops low-energy, high-efficiency silica defense. Rust pigments, anti-rust pigments have many advantages such as high specific surface area, low solubility, reduced foaming and permeability, stable pH value, etc., added to the coating, can effectively improve the corrosion resistance of the coating. With the increasingly stringent environmental requirements, anti-rust pigments containing heavy metals, such as chromate products, will be driven out of the market, while anti-rust products based on non-toxic and harmless amorphous silica will become anti-rust products. A dazzling star in the rust pigment market. At present, silica antirust pigments have been well applied in home appliance sheet coatings.
廣州凌瑋科技股份有限公司應用部部長王善
On May 14th, Wang Shan, the application minister of Guangzhou Linghao Technology Co., Ltd., was invited to the online class to bring the wonderful course of the theme of "China's national defense rust "silicon future" has come. Wang Gong explained the audience to the audience in the course. The characteristics of silica anti-rust pigment products and their introduction in practical applications. Silicon anti-rust pigments can not only solve the conversion problem of products, but also have the characteristics of low market energy and high efficiency.
Amorphous silica production process
There are two kinds of amorphous silica synthesized by the aqueous phase method: divided into precipitated silica and gelled silica, which control different reaction temperatures, control different reaction time, reaction temperature and pH during the synthesis. , thereby controlling the structure of the particles. The precipitation method is generally carried out under alkaline conditions. In an alkaline environment, the initial silica particles will slowly expand to form porous secondary particles. Under the action of van der Waals force, the porous particles slowly aggregate and form loose. Stacked particles. The characteristics of this type of silica are: low specific gravity and low hardness.
The gel method is a reaction under acidic conditions. Under acidic conditions, the reaction is relatively slow, the first-order particles are in the form of a sol, and the sol particles are slowly aggregated. After that, the numerous particles are stacked into a large, mesh-like structure. Harder gel silica particles. Such silica products have a large specific surface area, are dense and relatively stable. The anti-rust pigment developed by Linghao Technology is based on the gel method and special surface treatment products.
Silica anti-rust pigment has high specific surface area, low solubility, enhanced long-term protection, stable pH, good dispersibility, excellent salt spray resistance, no heavy metals, phosphate, etc. It is an environmentally friendly environment. Friendly product. Silica anti-rust pigments have a wide range of applications and can be applied to almost all iron substrates. At present, Ling Xiao has been well promoted and applied in the field of light anti-corrosion such as home appliance panel, powder coating, coil coating, engineering machinery coating.
Mechanism of action of silica antirust pigment
二氧化硅防銹顏料作用機理
During the live broadcast, Minister Wang introduced the anti-rust principle of Lingxiao silicon anti-rust pigments with vivid animation. Linglong Technology LM series ion exchange type anti-rust pigment is a kind of anti-rust pigment obtained by exchanging calcium and magnesium species on the silica surface with silica. These anti-rust pigments do not contain any heavy metals and phosphorus species and can cope with any future environmental policies and regulations. Taking the LM30 containing calcium as an example, the principle of rust prevention of ion exchange type antirust pigments is introduced.
Corrosion of all iron-based substrates, including galvanized surface treated iron-based substrates under natural conditions, results from two electrode reactions. 1. Anode: Under the influence of attack ions, such as chloride ions, the iron atom loses two or three electrons into ferrous or iron ions; 2. Cathode: oxygen and water penetrate the paint film and combine with electrons on the surface of the substrate. , generating hydroxide ions. The ions move in the paint film, and finally the iron hydroxide and oxide are produced, causing the substrate to
LM30 has a high specific surface area, which is dispersed in the paint film to adsorb attack ions and delay the formation of ferrous or iron ions. On the other hand, silica will dissociate under alkaline conditions, releasing silicate ions. . When the cathodic reaction occurs and the regional alkalinity increases, the hydroxide ions are consumed to release the silicate ions. Silicate ions and calcium ions, ferrous or iron ions form insoluble silicates, covering the surface of the cathode and the anode to form a passivation protective film, thereby blocking the occurrence of the reaction between the anode and the cathode. Therefore, the LM30 achieves the effect of rust prevention from both physical and chemical levels.
Application of silica antirust pigment
Silica anti-rust pigments, mainly reflecting environmental performance, are therefore focused on applications in waterborne coatings.
Good dispersion, ultra-fine powder, no need for grinding
Due to the slow reaction speed of silica-based silica, it is recommended to add anti-flash rust additives to the formulation for rapid rusting. In the preparation process, silica is ultra-fine powder without grinding. After grinding other products and pigments, add Lingqi LM-30\LM-50, and disperse it at high speed of 1200 rpm for 10 minutes. The test fineness of silica can reach 18 microns, which is completely in line with the primer. The fineness requirements. During the test, the formula can be easily debugged without grinding, and the relevant data of rust prevention effect and addition amount can be grasped.
Excellent salt spray resistance
In the waterborne epoxy system, cold-rolled thick steel plate is selected as the substrate, LM-30\LM-50 is added in an amount of 5%, the film thickness is 50-60 microns, and neutral 5% brine is continuously sprayed. When LM-30 and LM-50 were added, the foaming time was doubled, the rust foaming became wider (two millimeters outside), and the aging time was extended by more than 500 hours.
Comparison of experimental data of waterborne epoxy system
It can be seen from the table that the same amount of addition, LM-30 is stronger than the salt spray resistance of the modified zinc phosphate and zinc phosphate. When the addition amount reached 12%, the salt spray resistance of LM-30 was increased by 120 h compared with the zinc phosphate product. It is 80h higher than the modified phosphate. It can be seen from the above figure that LM30 has obvious advantages over phosphate products. It is theoretically inferred that LM30 ion exchange type anti-rust pigment can be used for indoor product coatings, which can increase the use time of phosphates for nearly one year. The coating prepared by the phosphate is longer than half a year.
Waterborne epoxy system 500h comparison chart
The advantage of LM-30 is not obvious when scratching. After entering the scratch time, LM-30 can effectively pass the passivation layer to ensure the control of foaming and rust seam widening time, and the performance advantage is very obvious.
買化塑在線課堂-中國防銹“硅”時代，未來 已來 直播截圖
This live broadcast course has received strong support from many domestic chemical companies. Can the self-crosslinking acrylic emulsion system be used during the live broadcast? The application of silicon anti-rust products, does the original formulation system need to be fully adjusted? Silica anti-rust pigment, is there any advantage in terms of cost? What is the price/performance ratio? On several technical issues, Minister Wang responded to the message at the live page.
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http://www.ibuychem.com/courses/details/762