Abstract: A device for preparing a liquid polymer blend is proposed having a storage container for the liquid polymer blend; a degassing device, which is arranged downstream of the storage container, for the liquid polymer; a gassing device, which is arranged downstream of the degassing device, for adding an additive gas to the liquid polymer blend; a homogenization unit, which is arranged downstream of the gassing device, for the polymer blend to which the additive gas was added; and an output line, which is connected to the homogenization unit, for the homogenized polymer blend.

Abstract: A roof element and a process for the production of a roof element are provided, which may have the steps of providing a polymer mixture; admixing an organosiloxane compound with the polymer mixture; a mixing of the polymer mixture, with the organosiloxane compound admixed, with an isocyanate compound to give a polyurethane material and introduction of the polyurethane material into a mold cavity of a foaming mold in a manner such that the polyurethane material reacts to completion and a molded section of the roof element is shaped in the mold cavity wherein the organosiloxane compound is accumulated at the surface of the molded section, wherein in a surface layer of thickness from 0.5 ?m to 20 ?m of the molded section, the organosiloxane compound is accumulated; and demolding of the roof element from the foaming mold.

Abstract: A device for preparing a liquid polymer blend is proposed having a storage container for the liquid polymer blend; a degassing device, which is arranged downstream of the storage container, for the liquid polymer; a gassing device, which is arranged downstream of the degassing device, for adding an additive gas to the liquid polymer blend; a homogenization unit, which is arranged downstream of the gassing device, for the polymer blend to which the additive gas was added; and an output line, which is connected to the homogenization unit, for the homogenized polymer blend.