| Resources: AGS Technology Inc., www.agstechnology.com |
Engineers at AGS Technology Inc., Schaumburg, Ill., have devised a better way to recycle plastic scrap and make it more suitable for injection molding. The company’s proprietary Injectoblend material lets it build less-expensive automotive and durable-goods parts compared to parts made from virgin plastic.
Traditional plastic compounders convert scrap plastic into injection-molding material by grinding and extruding it into pellets. In contrast, Injectoblend is molded directly, eliminating expensive extruding operations. The company performs its own injection molding using the so-called “salt-and-pepper” regrinds. They are put in injection-molding machines and shot directly into the mold.
AGS Technology molds most components from engineered materials such as glass-filled nylon. Materials can come from scrap such as worn-out McDonald’s signs. Other sources include polyethylene terephthalate (PET) beverage container caps, compact disks, and 5-gallon polycarbonate water jugs.
“Our verification process includes molding ASTM or ISO specimen bars from recycled material, testing them in our lab for various properties, and benchmarking these test results to internal part specifications,” says Virgis Gudeika, AGS director of technology. “In addition, our cleaning, segregating, homogenizing, testing, and formulating methods eliminate the variability that stymied injection molders trying to use recycled materials in the past. We also add modifiers to get certain properties,” he says. “For example, modifiers are necessary for polycarbonates to make them more ductile at low temperatures.”
A crucial aspect of AGS Technology’s operations is that its injection-molding machines, drying units, and material-handling equipment are specifically designed to use recycled plastic. “It is necessary to dry many materials before they are molded,” says Gudeika. “That’s because plastic, which is made from carbon polymer chains, tends to absorb moisture. Water causes hydrolysis, which breaks the chains. Typically, hydrolysis makes impact-resistant plastics brittle,” he says.
On one PC/ABS job, the company uses 250,000 lb of material a year, says Gudeika. “The cost difference between Injectoblend and a virgin resin in this case is $0.80/lb. This saves our customer $200,000 annually and without sacrificing quality.”