Melamine foam sponge is a foam-like material consisting of a formaldehyde-melamine-sodium bisulfite copolymer. The foam is manufactured by several manufacturers worldwide. It has been used for over twenty years as insulation for pipes and ductwork, and has a long history as a soundproofing material for studios, sound stages, auditoriums, and the like. The low smoke and flame properties of melamine foam sponge prevent it from being a fire hazard.Melamine foam sponge is the active component of a number of abrasive cleaner sponges. It is also used as the main sound and thermal insulation material for bullet trains, due to its high sound absorption, excellent thermal insulation performance and light weight.