The heat resistance, cold resistance and temperature denaturation resistance of the coating film are the ability of the coating film to resist the change of environmental temperature. For the coating film of different products, the measurement items corresponding to the environment should be carried out.
(1) The heat resistance of the coating film refers to the ability of the coating film to resist high temperature, that is, the ability of the coating film to maintain its original performance after a certain period of time and under certain high temperature conditions.
The method of measuring heat resistance is: prepare four test samples according to the requirements, put three of them in a high-temperature oven adjusted to the test temperature, take them out after the specified time and cool to room temperature, and leave one template for comparison. If the baked sample has no defects such as peeling, bubbling, wrinkling, discoloration and cracking, it is considered qualified. (Related instrument: oven)
(2) Cold resistance is the ability of the coating film to resist low temperature. Generally, this requirement is required for architectural coatings used in cold regions. The measurement method is: put the prepared coating film sample into a low-temperature box at -40°C or -60°C, keep it for a certain period of time, take it out, and observe the change of the coating film.
(3) Temperature denaturation resistance refers to the ability of the coating film to resist sudden changes in ambient temperature. There are two methods for the determination of resistance to temperature denaturation: dry and wet, and the dry method is generally used. The specific measurement method is: prepare a test sample according to the requirements, and then put the sample into a refrigerator at -40°C or -60°C, and after a certain period of time, put the sample plate into an Incubator at +60°C for 1 hour. This is a test cycle. After several cycles according to the requirements of the product regulations, it is considered qualified when the surface of the coating film sample is free from blisters, wrinkles, cracks and other defects.
