The composition of the sponge is: polyurethane soft foam rubber, polyurethane is the most common polymer material in daily life, and is widely used to produce various "sponge" products.
There are three types of sponges currently sold on the market:
1: Polyurethane type, which generates a large amount of cyano-containing gas by combustion. These gases are highly toxic and have strong suffocation.
2: Polyethylene type, which generates carbon-containing gas by combustion. This type of gas is less toxic.
3: Polystyrene type, this type of foam burns and decomposes a small amount of styrene monomer, which is toxic, but its toxicity is not as large as polyurethane.