Correlation between Permeability of Surface-Treated Glass Cloth/Resin and Capillary Number Taking into Account of Contact Angle

Abstract

In this study, we experimentally evaluated the correlation between the microscopic flow and permeability of a glass cloth, which was modified using a silane coupling agent. We focused on the capillary number, which is a parameter determining the microscopic resin impregnation behavior within and between fiber bundles. The capillary numbers were classified into different parameters based on their temperatures and pressures. First, we obtained the temperature condition, and resin viscosity/(surface tensionz⋅contact angle) ratio based on temperature, which was constant for each resin. Under these temperature conditions, the pressure condition of the resin impregnation rate was made constant. The permeability was evaluated for different resins under the conditions of temperatures and pressures making vary the capillary numbers in three conditions. As a result, the permeabilities of the different resin systems were approximately equal. Therefore, it was found that the macroscopic permeability was not significantly influenced by the capillary number representing microscopic resin flow.