Coating chemical resistance measurement is a method to evaluate the stability of coatings in chemical media. It is mainly used to test the durability and chemical stability of coatings in chemical media.
Coating film chemical resistance determination is usually tested using a chemical resistance test, which can use a variety of chemicals as media, such as acids, alkalis, organic solvents, etc., to test the durability and chemical stability of the coating in these media. In the test, the coating sample is immersed in a chemical medium and tested for a certain period of time. During the test, changes in properties such as appearance, color, adhesion, weight and hardness of the coating sample are detected to evaluate the chemical resistance of the coating.
Coating chemical resistance measurement can be used to evaluate the durability and stability of various types of coatings, such as automotive paints, architectural coatings, chemical coatings, etc. By measuring the performance changes of coatings in chemical media, the durability and life of coatings can be predicted, providing basic data for formulating coating maintenance and improvement programs.
The test methods for chemical resistance of coating films generally include the following:
Immersion method: The coating sample is completely immersed in a specific chemical, and the changes of the coating are observed within a certain period of time. Usually evaluated using indicators such as visual observation, microscopic observation, weight change, and surface hardness change.
Dissolution method: Dissolve the coating sample in a specific chemical and observe the dissolution of the coating in the chemical. Usually evaluated using methods such as visual observation, microscopic observation, and electron microscopy.
Wiping method: Use specific chemicals to wipe the surface of the coating, and then observe the changes in the coating. Usually evaluated using indicators such as visual observation, microscopic observation, and surface hardness changes.
Soaking-wiping method: Soak the coating sample in a specific chemical for a certain period of time, then perform a specific wiping, and finally observe the change of the coating. Usually evaluated using indicators such as visual observation, microscopic observation, and surface hardness change.
According to the provisions of the national standard "GB1763- (79) 88 Method for Determination of Chemical Reagent Resistance of Lacquer Film", dip or brush the tested paint with ordinary low carbon steel rods, measure the thickness after 7 days of drying, immerse 2/3 of the area of the test rod in the acid or alkali specified in the product standard, and soak it at a temperature of (25 ± 1) ℃. Observe and check the condition of the coating film regularly, and determine the result according to the product standard.
NBCHAO reminds you that different types of coatings and application fields may require different test methods and standards. In actual testing, appropriate test methods and standards should be selected according to specific conditions to obtain accurate and reliable test results. At the same time, attention should also be paid to the uniformity and repeatability of test conditions to ensure the comparability and reliability of test results.
