Butyl sheets are a type of synthetic rubber that are known for their excellent impermeability to gases, air, and moisture. They are made from a copolymer of isobutylene and small amounts of isoprene, which gives them their unique properties.Butyl sheets are commonly used in a variety of industrial applications, including as a waterproofing material for roofs, foundations, and other structures. They are also used as a sealing material for pipelines, tanks, and other containers that require a high level of impermeability.