How should prepreg be stored?

Prepregs are typically stored refrigerated; for example, HexPly prepregs from Hexcel Corporation in the US are typically stored in a -18°C cold storage facility. 

To prevent moisture absorption, the prepreg should be allowed to warm to room temperature before opening the polyethylene bag (warming to room temperature for an intact package may take up to 48 hours).

Generally, at -18°C, the shelf life of prepregs is 12 months from the production date. The shelf life at -18°C and at room temperature is usually printed on the label of the prepreg product packaging. 

The tack life and external life of prepregs at room temperature (23°C) will vary depending on the type of resin.

Hygiene and safety measures when using prepreg

• The prepreg is covered with a protective film before laying; the film is removed after cutting, therefore, direct contact with the prepreg is practically nonexistent.

• Unlike wet processes (dry fibers, liquid resin), the prepreg process produces very little fiber dust and eliminates splashing, leakage, and spillage.

• Prepreg does not volatilize at room temperature.

• At room temperature, the prepreg's viscosity is at a low to medium level.

However, all prepregs should still be handled with caution, such as always wearing gloves that cover the arms to avoid skin contact with the product. 

Repeated touching of prepregs without protection can cause allergic reactions.

Processing cured products will generate dust containing fibrous materials, which should be avoided from inhalation. It is recommended to install a dust collection device in the cutting area. 

To prevent fire and explosion, dust formation should be avoided during the processing of cured products, and sources of ignition should be kept away. Dust containing carbon fibers is conductive.