RTM Molding: Definition
Resin Transfer Molding (RTM) is commonly referred to as liquid molding. With this process, a resin is mixed with a catalyst (hardener) and injected into a mold that contains dry fibers, such as fiberglass. A static mixer regulates the ratio of polyester resin to catalyst. Usually a ratio of 100:1 of resin to catalyst is used. The mixture is then injected at a low pressure of approximately 5 psi into the mold. The reaction time is usually minutes.