PROCESS AND APPARATUS FOR PRODUCING PLASTICS AND POLYMERIC FOAM

摘要

A process and apparatus for producing polyurethane foam, comprising bringing together under pressure one or more foam components and a gaseous CO2 auxiliary blowing agent and discharging the combination through a permeable discharge head in the form of plural individual wire meshes sintered together to form at least one composite element having a structure such as to require repeated division, divergence, convergence of flow paths and impingement of the individual flows with the sintered wire mesh and the flows through adjacent pores in three dimensions within its axial thickness, considered in the direction of flow therethrough, and at which the pressure is reduced for forming a froth, wherein the combination of the foam components and the gaseous CO2 auxiliary blowing agent is arranged to be in a non-homogeneous state containing gas bubbles prior to passage through the discharge head.