A “SEE-THROUGH ” EXTRUDER TO TEACH PRINCIPLES OF POLYMER MELT EXTRUSION

The design and construction of a simple and inexpensive single screw extruder with a transparent quartz barrel is presented. The utility of such an extruder as an effective teaching tool to visually portray the mechanisms of polymer melting and mixing during extrusion is outlined. BACKGROUND The plastics industry in the USA employs more then 2.2 million people, which represents about 2 percent of the workforce. Revenue generated from shipment of plastics and plastic products exceeds $ 400 billion, which positions this industry as the nation’s fourth largest in terms of manufacturing (1). The plastics industry continues to grow at about 2 % annually. Extrusion is the most popular process used to fabricat