Abstract: A novel dielectric heater including a RF source having a first impedance, a parallel plate mold having a second impedance, and an impedance network, matching the first impedance to the second impedance, connected to the RF source and the parallel plate mold. The impedance network may be connected in series with the RF source and the parallel plate mold. The RF source may include a RF terminal and a common terminal, the impedance network may include a first terminal, connected to the RF terminal, and a second terminal, and the parallel plate mold may include a first plate, connected to the second terminal of the impedance network, and a second plate, connected to the common terminal of the RF source. In an alternative embodiment the novel dielectric heater includes parallel plates divided into a number of series-connected cells. The series cells lower the capacitive component, and may be configured such that an impedance of the parallel plate mold approximates an impedance of the RF source.

Abstract: A compound and method for dielectrically heating plastic in a mold with an RF source. A novel molding compound includes, in one embodiment, plastic such as polystyrene having a first dielectric constant and a water based resin such as phenolic resin. A lossy additive, such as a chemically inert low dielectric material, having a second dielectric constant substantially lower than that of the plastic, is added to the molding compound. The lossy additive increases the RF energy absorbed by the plastic molding compound thereby reducing heating time in the mold.