| 摘要 |
The invention relates to a method for the production of foamed micro-porous polymer moulded bodies by melting a thermoplastic polymer in a first zone of an extrusion device; mixing a highly-volatile propellant; conveying the polymer melt containing the propellant into a second zone, wherein the propellant dissolves until the polymer melt is saturated at the foaming temperature; moulding and foaming the charged polymer melt to form a foam structure. In the second zone, a pressure greater than 90 bars, a propellant concentration greater than the critical threshold concentration for a complete foaming and a foaming temperature greater than the setting temperature of the polymer melt saturated with the propellant. The obtained polymer moulded body has a porosity in the region of between 40 and 90 vol.- % and an evenly open-pore structure evenly distributed over the cross-section. The foamed micro-porous polymer moulded bodies in particle-shaped form are made of a thermoplastic polymer having an even open-pore structure, a porosity of between 40 and 90 vol.- %, an accessible portion of pore volume of at least 0.75, in addition to an average cell size of between 1 and 100 ?m. |
