What is convoluted foam?
Convoluted foam is a synthetic textile made from polyethylene that is used as protective packaging and lining material for a variety of products. It is initially produced in flat sheets that are anywhere from one to eight inches in thickness (2.54 cm to 20.32 cm), which are then saturated with a thermosetting resin, such as trimethylol melamine or benzoguanamine. The sheets are then passed through a machine that convolutes one side with special die cutters, creating the characteristic egg crate pattern. The sheets are then cut in half to obtain two sheets that are compressed with this pattern on only one side so that they may be nested in pairs. The nested pairs are then treated with ethylene-acrylic acid or butene-maleic anhydride, cross-linking copolymers that react with the thermosetting resin to produce enough rigidity that the foam may stand on its own.