China Coatings Online News Information Abstract: A antifreeze-resistant viscose coating based on epoxy resin was prepared, and the effect of the test influence factors on the frozen viscosity strength of the coating was determined by orthosoltic test. Finally, by comparing the contact angle of the sample and the shear-frozen viscosity strength between the sample and the water, it is found that with the increase of the contact angle, the freezing viscosity is gradually reduced, and the content of 17 fluoro-fluorine-based triethyl silane has little effect on the hydrophobicity of the epoxy resin-based antifreeze viscose coating.
key words: low-energy surface; nano-silicon dioxide; antifreeze stickiness; hexafluorocarbon-triethylsilane
in the chart classification number: TQ630. Document identification code: Bdoi:10. ３９６９／ｊ． ｉｓｓｎ． １６７４－３４０７． ２０１４． ０３． 004
1. Introduction to frozen stick is a common natural phenomenon in the northern region, it is a special environment under the joint action of low temperature and water adhesion phenomenon. The problem of frozen stick is closely related to people's daily life and industrial and agricultural production, and the existence of frozen viscous layer seriously affects the interaction between working parts and the outside world, which brings a lot of inconvenience to production and life, consumes resources, accelerates the loss of parts, reduces the efficiency and reliability of production and work, and causes major accidents in severe cases. Cao Min and others used the test optimization design to study the effect of PMMA surface form on the strength of ice attachment, Yan Yingdi and others reviewed the development direction of ice-resistant coating and the main problems existing in the design and preparation of the coating material, and Long Yin and others studied the accumulation of water on the surface with the change of the contact angle of aluminum-based hydrophobic water. Because most of the antifreeze viscose coatings developed at present have the problem of coating curing and substrate bonding is not secure, which affects the practical application of antifreeze viscous coatings, so this paper mainly studies epoxy resin as the main raw material with the substrate is not easy to fall off anti-freeze viscosity coating.
2. 1 Test material
a number of disposable plastic cups, bisphenol A epoxy resin (E44), xylene solution, ordyl alcohol solution (Tianjin Fuyu Fine Chemical Co., Ltd. analysis of pure AR), γ - amino triethylsilane (KH-550), nanoscale Silicon dioxide powder, hexafluoroethylene triethyl silane, wet dispersant (110), amine epoxy resin curing agent, iron trioxide powder, leveling agent (354), polished metal sheet, filtered copper mesh, beam, waterless ethanol.
２． 2 Test equipment
stirring sand sand scattered multi-purpose machine, BGD750/1, Guangzhou Standard Gerda Laboratory Instrument Supplies Co., Ltd.; ２． 3 Test method
a solution backup with xylene and orthodol mass ratio (4:1). Weighing 20g configured solution, adding γ-amphetamine triethyl silane (KH-550), dosing 2% of epoxy resin dosing, adding quantitative nano-silicon dioxide powder and quantitative hexafluoroethylene triethyl silica. After mixing the mixture evenly, add it to the dispersing machine and disperse 30min (1300r/min) at high speed, so that the hexafluorine and nano-silicon dioxide are fully evenly dispersed. Add quantitative epoxy resin, add wet dispersant (110), after dispersing 30min with a dispersing machine, add grinding beads, disperse the roors for grinding roors, and then high-speed grinding 2h, according to 2% of the amount of epoxy resin added iron red and leveling agent (354), high-speed grinding 10min, the grinding mixture filtered with copper filter, sprayed with spray gun solidification. The orthosecting test was used to study it.
3. The results of the experiment and the
the test results are shown in Table 1-Table 3.
can be obtained after the comparison: three factors for the strength of frozen viscosity affect the size of B>A>C, after comparison can be obtained the optimal combination is: A3B1C1.
Through the orthographic test results of 9 sets of tests and the observation of the frozen viscosity of ice on the coating surface, the observation of laser confocus microscopy (see Figure 1) and the contact angle of water (see Figure 2), it can be seen that the contact angle of several groups with larger freezing strength is smaller than that of other groups, while the contact angle of several groups with smaller freezing strength is larger. It can be seen from the micromorphological structure map that the surface structure with less frozen viscosity has certain regularity and uniformity in a certain direction, the surface reunification phenomenon is small, and the surface microstructure with larger frozen viscosity strength has a certain reunion phenomenon, the nano-silicon dioxide dispersion is not very full, and the surface is not structural regularity and direction in a large area. Therefore, the frozen viscosity of the coating decreases with the increase of the contact angle, and the 17fluorocarbon-based triethyloxysilane does not migrate well to the surface of the coating, and the whole coating does not show low surface energy and good hydrophobic properties.
the frozen viscosity device between ice and coating measured in this paper and its schematics are shown in Figures 3 and 4. First inject 5 ml of deionized water into the cup, put the well-sealed device into a thermostat at -20 degrees C, freeze treatment 1h, remove immediately with the test device for ice-to-coating bonding strength test.
Coating a fluorine-containing hydrophobic coating on the surface of the metal substrate is conducive to reducing the freezing strength between ice and coating, which provides a theoretical basis for using ultra-hydrophobic coating to solve the problem of frozen adhesion.