Melamine sponge is a foam-like material made of a melamine-formaldehyde condensate. It is the active component of a number of abrasive cleaner sponges, notably the Magic Eraser. Melamine sponges are air-filled latticeworks of a material called formaldehyde-melamine-sodium bisulfite copolymer. They are used as an effective abrasive cleaner and can remove crayon, marker pen, and grease from painted walls and wood finishings, plastic-adhering paints from treated wooden tables, and adhesive residue and grime from hubcaps. Melamine sponges act as an extremely fine sandpaper that can scrape away unwanted scuffs, with no soap required. They are also used as insulation for pipes and ductwork, and as a soundproofing material for studios, sound stages, auditoriums, and the like. Melamine foam is a thermosetting foam with a highly networked cross-linked structure system. It has higher heat stability and cold resistance compared to traditional polyethylene, polypropylene, and polyurethane foam with low cross-linking degree.