prepregkompositer

Prepreg composites, or prepregs, are fiber-reinforced polymers in which reinforcing fibers such as carbon, glass, or aramid are pre-impregnated with a resin system that is partially cured (the B-stage). This yields a tacky sheet or tow that can be laid up and later cured to a solid laminate. The resin content and cure behavior are controlled to achieve a consistent fiber volume and low porosity.

Most prepregs use thermoset resins, especially epoxy, cyanate ester, and BMI, but thermoplastic prepregs (for example based on PEEK or PPS) also exist. The choice of fiber and resin determines properties and processing requirements. Prepregs are typically stored cold, often at -18 to -20 C, to slow cure; shelf life ranges from months to over a year depending on the system. Before layup, material is acclimated to use temperature.

Manufacturing involves stacking the prepregs on a mold, removing air with vacuum and applying heat and pressure. Autoclave curing is common in aerospace to improve consolidation and reduce porosity; out-of-autoclave ovens or compression presses are also used for different parts and production scales.

Advantages include high fiber content, predictable resin distribution, and low porosity, yielding high strength and stiffness. Limitations include high equipment and process costs, stringent storage and handling requirements, and shorter shelf life relative to non-prepreg materials, as well as repair and inventory considerations.

Applications span aerospace structures, automotive components, wind turbine blades, and sporting goods—any area where weight reduction, stiffness, and reliability are critical. Safety and quality-control measures focus on proper storage, moisture control, and laminate inspection to ensure consistent performance.