For all glass fiber reinforced materials, the permeability and penetration are affected by fiber diameter, tow tex number and fiber dispersion. Permeability describes the wetting of glass fibers. Immerse all glass fiber reinforced materials, and the permeability and penetration are affected by fiber diameter, tow tex number and fiber dispersion. Permeability describes the wetting of glass fibers. Immersion describes the ability of a resin to penetrate multiple layers of reinforcement.
Two examples are given: the extremely fine microstructure of glass fiber felt is saturated very quickly, because the fibers are well dispersed, the monofilament diameter is small, and the fiber surface quality is high. However, the resin cannot penetrate the reinforcing material in the lower layer soaked by the thin felt. In fact, if air is carried into the resin, bubbles may become permanent cavities in the laminated product.
On the other hand, continuous strand mats made of roving usually have excellent impregnation properties, allowing resin and entrained air to pass quickly through the mat structure. In roving felt, the monofilament may be wetted more slowly in a large tow, but the bubbles are easier to separate from the laminated structure</ div>