Abstract: Applying a brushed coating film-forming method of polyvinylidene chloride (PVDC) emulsion to enhance the moisture resistance of carbon fiber composites is viable. Compared to the prefabricated PVDC film application method, it offers advantages such as a simple process, high operability, good adaptability, the formation of a sealed moisture barrier cavity, lightweight properties, and controllable thickness. The cured PVDC film exhibits strong adhesion to carbon fiber composite materials, making it suitable for equipment applications, such as composite material launch boxes (cylinders), that require high moisture insulation performance.

Key words: polyvinylidene chloride; moisture permeability; composite material