Evaluation of Methods for improving the wetting of Fibers by the resin in Prepreg Manufacturing Process

Prepreg is a pre-engineered laminating material manufactured by impregnating a fiber-reinforcement with a resin. Wetting of fibers by the resin is one of the key parameters in prepreg manufacturing process, because of its contribution on the mechanical properties of the prepreg. It is worth mentioning that there are two main mechanisms for increasing the wetting of the fibers by the resin; the first one is through the formation of chemical bonds between the resin and fibers, and the second one is increasing the ability of resin to penetrate through the fibers and make mechanical entanglement between the resin and fibers. Various methods exist to achieve both these mechanisms, such as, surface modification of fibers, changing the resin formulation, increasing the contact time between resin and fibers, and reducing the viscosity of the resin. In this paper, advantages and disadvantages of the above-mentioned methods are evaluated. In general, it can be said that increasing the wetting of fibers by the resin alone cannot be considered as a target in prepreg manufacturing process, because in orderto improve the wetting of the fibers by the resin, there should be changes made in other conditions of the produced prepreg such as mechanical properties, final price, production time, etc..Therefore, finding the optimal values for the parameters like wetting of the fibers by the resin is essential.