Foam molding of poly (meth) acrylimide particles in tools closed for the production of rigid foam cores

The invention relates to a process for the production of foamed molded poly (meth) acrylimid- (P (M) I-), in particular polymethacrylimide (PMI) cores that may be used for example in automobile or aircraft. The method is thereby characterized in that a polymer granule or powder is filled into a pressing tool and is foamed there. In particular, the method is characterized in that this two-shell die comprises two sides each have a contour following cavity, both for heating and for cooling of the granulate or of the rigid foam core are formed therefrom.