abstract |
A method of producing an extruded plastics foam of enhanced physical strength includes intimately mixing a blowing agent incorporation CO2, the major portion of which is a natural gas, in a plastics resin melt to form a homogenous resin mix, and extruding the resin mix through an exit die into a region of lower pressure. At the point of extrusion out of the exit die, the temperature of the resin mix is adjusted so that it is below the critical temperature. |