Polymerisation is the first basic step in plastics production. Depending on the monomers, it can be carried out in bulk, in a solution, or in an emulsion. If monomer solutions are introduced into the reactor, they are first filtered to separate impurities. Filtration is also used after polymerization to recover monomer residues from polymer solutions/suspensions and to return them to the polymerization reactor. Thermoplastics are an important class of plastic raw materials, like polyamide (PA), polymethyl methaycrylate, polycarbonate, or polyether ether ketone (PEEK). After polymerisation, these materials are either directly granulated for further processing elsewhere, or they are directly melted and processed by extrusion or injection moulding. Our screen changers and melt filter systems are used in this stage.