Phenolic insulation board, as the most important thermal insulation material, is now known as the king of thermal insulation materials. Phenolic board is made of phenolic foam material, phenolic foam material is a polymer rigid aluminum foil foam product, and is made of thermosetting phenolic resin. Phenolic foam is mainly produced by phenolic resin and adhesive, and its molecular density is very small, in other words, the gap between the materials is very small. Therefore, it has good waterproof and moisture resistance. The water absorption of phenolic board is less than 7% by industrial instrument test.

Polymer structure of phenolic board makes it have very good closed-cell structure. In the environment of large temperature difference between day and night or environment, the ability of waterproof vapor permeation is very strong. In order to keep cool, the requirement of water vapor condensation permeation is very good. Conventional thermal insulation materials, because they do not have very good closed-cell structure, can only be used in the environment of large temperature difference between day and night. Under constant ambient temperature, if used under changing ambient temperature, it is necessary to change the detection frequently, and phenolic board can solve this problem very well, which is also the main reason why phenolic board has such good waterproof and moisture-proof performance.