Abstract: The rheological behaviors of bismaleimide resin (4503A) for resin transfer molding (RTM) are studied with DSC and viscosity experiments. A viscosity model is established and used to simulate rheological behaviors of the resin. It is shown that subsection viscosity models should be employed to describe the viscosity characteristics of the resin because of the different curing mechanisms of the resin at different temperatures. The estimated viscosity of the models is in good agreement with that of the experiments. The low viscosity plaque and a processing window of the resin are determined based on the developed models. The optimum processing parameter of the 4503A resin for RTM is 80℃ at which the viscosity of the resin will be less than 300cP within 71 minutes. The developed viscosity models will be important for processing simulation and quality control for high performance composites of RTM processing.

Key words: compo sites, RTM, resin, visco sity, simulat ion