Resins act as the matrix of the composite material, impregnating the fibers and giving cohesion to the final structure. They provide compressive strength, adhesion between layers, and dimensional stability, maintaining the correct orientation of the fibers.
There are different types of resin, with the most common being polyester, vinylester, and epoxy. Their use adapts to different manufacturing processes such as manual laminating, vacuum bagging, infusion, RTM, or pre-impregnated systems.