Microcellular Foam Offers Processing Advantages
Canadian Plastics
At an SPE Quebec meeting last fall, Matt Pallaver, president of Trexell Inc. (Woburn, MA), described the company's Mucell microcellular foam process for making injection molded parts. The process gene...
At an SPE Quebec meeting last fall, Matt Pallaver, president of Trexell Inc. (Woburn, MA), described the company’s Mucell microcellular foam process for making injection molded parts. The process generates microcellular foams in the range of 5 to 50 microns utilizing carbon dioxide or nitrogen gas in the state of a supercritical fluid. The liquid gas is introduced into the melt creating a solution with a much lower viscosity. As a result, says Pallaver, a molder can reduce the processing temperature of a given material by as much as 75 to 100F, which reduces molded-in stress and cooling time and speeds up cycle time.
Because the micro-cellular bubbles are so tiny, finished part integrity and properties are maintained, even in thinwall sections, Pallaver notes. The table above provides some typical weight reductions of parts using the Mucell process, as reported by Trexell at the 1999 Structural Plastics conference.
Material | Part | % weight | thickness | reduction |
PS | 1.52 mm | 50 | ||
PP | 2.28 | 30 | ||
HDPE | 5.08 | 60 | ||
Nylon | 2.54 | 19 |