Research conducted at the University of Massachusetts at Lowell shows nanoscale features can be injection molded from thermoplastic polyurethane.
In a presentation at Antec 2007 in Cincinnati, Michael Alabran said the study looked at how tooling geometry and molding conditions affected the ability to replicate the nanoparts. The researchers used a tiny mold made of etched silicone wafers.
They found TPU was more difficult to mold than control parts molded from polycarbonate. The TPU tended to stick to the silicone tooling and stretch, making it hard to eject the parts. PC features tended to break off during ejection, Alabran said.
Replication of the nanoparts was improved by using a vacuum system to remove air from the mold before injection.
Researchers also learned higher mold temperatures improve part quality.
Alabran is technical director of Plastics Services Network in Erie, Pa.