Polymer Processing Institute


1.25" diameter, 40:1 L/D, Segmented Single Screw Extruder for Gas Injection Foaming

 The single screw extrusion foaming apparatus consists of a 1.25" diameter segmented single screw extruder, volumetric resin metering feeder, gas/liquid injection system and die. To monitor the temperature, pressure and the gas flow rate, transducers were placed at strategic locations and the process variables are recorded. A data acquisition system and digital computer are used to display the variables in real time.







The transducers are connected to fifteen bit accurate digital to analog converters. The converters are connected to the serial port of an IBM digital computer. The visual graphical interface and related computer coding was developed at PPI. The picture shows the computer monitor displaying independent and dependent variables as function of time.





The picture shows the 10" wide flat sheet die being used to extrude PET foam at a density of 0.2 g/cc. This foam was produced using reactor modified PET and carbon dioxide gas. A three roll stack takeoff, equipped with constant temperature controller, was also used. Similar experiments were conducted using argon and nitrogen as physical blowing agents.

For more information please contact

Dr. Niloufar Faridi

(973) 596-5665