In the industrial sector, coatings are not just used to give objects color or provide aesthetic decorative effects. More importantly, coatings provide a protective barrier for various materials, protecting them from environmental, chemical and other aggressive substances. The chemical resistance of coatings directly determines their protective effect in practical applications, so the determination of this performance is particularly critical.
1. Chemical resistance: key performance
With the development of the chemical industry, various chemicals are increasingly used in production and daily life. This makes many materials, especially metal materials, may be exposed to various chemicals during use, resulting in corrosion, discoloration or other forms of damage. This damage will not only affect the appearance of the object, but more importantly, it will reduce its service life and even threaten its structural safety.
In order to solve this problem, a variety of chemical resistant coatings have been developed. These coatings can provide an effective protective barrier to the object being coated against chemical attack.
2. Determination of chemical resistance
According to the national standard GB/T 23989-2009 "Determination of solvent wiping resistance of coatings", the chemical resistance of coatings is mainly determined by solvent wiping resistance. The standard stipulates two main measurement methods: manual wiping method and instrument wiping method.
(1) Manual wiping method
The manual wiping method is a simple and intuitive measurement method. The Tester uses a specific chemical solvent, such as methyl ethyl ketone or xylene, soaks it on the absorbent cotton, and then wipes the coating surface back and forth at a certain pressure and speed. By observing whether the coating surface is damaged or the substrate is exposed after wiping, the chemical resistance of the coating can be judged.
(2) Instrument wiping method
Compared to manual wiping, the instrument wiping method is more scientific and accurate. This method is tested using a special solvent-resistant wiping instrument. The instrument can provide constant wiping pressure and frequency to ensure the accuracy and repeatability of the test.
3. The significance of the measurement
The determination of the chemical resistance of coatings is not only to meet the requirements of national or industry standards, but also to ensure that the coating can provide effective protection in practical applications. Good chemical resistance means that the coating can maintain its protective effect in complex chemical environments, prolong the service life of the coated object, and reduce the cost of repair and replacement.
4. Development trends
With the advancement of science and technology and the increasing demand for environmental protection, the coatings industry is moving towards a more environmentally friendly and efficient direction. Future coatings not only require good chemical resistance, but also need to have various other properties, such as self-cleaning, antibacterial, UV resistance, etc. In addition, with the application of nanotechnology, nano-coatings have also become a research hotspot. These coatings have super chemical resistance and many other excellent properties.
Conclusion
The study and determination of chemical resistance of coatings is an important part of coatings science, which is directly related to the effect and value of coatings in practical applications. Only by continuous research and innovation can we develop more efficient and environmentally friendly coatings to meet people's growing needs
