Resin transfer molding of composite materials that emit volatiles during processing

摘要

A method and apparatus for resin transfer molding composite materials that emit volatiles. The apparatus includes an RTM tool, a constant displacement injection pump, a heater connected to a power supply, one or more porous tool inserts, and one or more articulated tool inserts. The porous tool inserts are mounted within the RTM tool and allow volatiles produced during processing to flow through the inserts. The volatiles are drawn through the porous tool inserts and out through an exhaust port. The articulated tools are also mounted within the interior of the RTM tool. The articulated tools are movable in order to increase and decrease the volume of the RTM tool. As volatiles are emitted, the articulated tools are moved in order to decrease the volume of the tool. The articulate tools are also used to apply a consolidation force to the resin and fiber-reinforced preform within the tool. In accordance with a method of the invention, an unpolymerized thermoplastic resin is thinned with an appropriate solvent to an acceptable viscosity. The resin is then injected into the RTM tool using a constant displacement pump. The tool is then heated causing the resin to polymerize and emit volatiles. Volatiles are withdrawn through porous tool inserts within the tool. After the majority of volatiles are withdrawn, the resin is consolidated to form a composite part.