Lanxess has developed a new polyamide 6 and polyamide 66 designed to overcome surface aesthetic problems typically encountered when injection molding with physical and chemical foaming agents. “Both materials produce excellent molded part surfaces that in most cases are smooth and flawless with virtually no opalescent streaks or areas that appear porous,” says Maik Schulte, a development engineer at Lanxess.
Foamed moldings are hot because they are up to 20% lighter than solid molded parts and also use less material. Of course, there are some compromises in some mechanicals, such as impact strength. Another benefit: foamed parts benefit from much lower distortion and exhibit virtually no sink marks. Mold cavity pressures can be reduced by up to 80 percent, which makes it possible to use smaller, less expensive injection molding machines with lower clamping forces. The mold is subjected to lower stresses, too, which means a longer, more cost-effective service life. In most cases, cycle times are noticeably shorter, which opens up further potential for savings.
The two new polyamides are reinforced with 35 percent glass fibers. Target applications include cylinder head covers, fan plugs/connectors, lamp sockets/holders and housing components for items such as thermostats and DIY tools.