How do I store my materials?

The storage aspects relevant to composites concern the shelf life of thermosetting resins. Thermoplastic resins have an unlimited shelf life, as they will not undergo polymerisation during storage. Epoxies are usually kept under refrigerated or freezer conditions to extend the storage life as long as possible.

Shelf life is defined as:
The length of time a liquid resin, packaged adhesive or prepreg can be stored under specified environmental conditions and continue to meet all applicable specification requirements and/or remain suitable for its intended function.

Pot Life is defined as:
The length of time that a catalysed resin system retains a viscosity low enough to be used in processing. There are some specific cases:
Polyester resins consist of a solution of polyester in a monomer usually styrene, the styrene acts to both reduce the viscosity of the resin and to cure the polyester. These resins have a limited storage life as they will set or "gel" over time. Generally inhibitors are added to the resin to extend the shelf life.

A new method know as an Encapsulated Cure System provides a new option for curing polyesters and vinyl esters. The process works by encapsulating a key component of the cure system in a polymer with a sharp melting point. When the melting point is reached the active ingredient is released and the cure process can begin. This means that the resin system has effectively an infinite shelf life at room temperature.