Chlorinated polyvinyl chloride, a thermoplastic substance that is more flexible and long-lasting and can resist greater temperatures, is the material used to make CPVC plumbing pipes. Hot and cold water, as well as other industrial liquids, are transported through these pipes.Chlorinated polyvinyl chloride, a thermoplastic substance that is more flexible and long-lasting and can resist greater temperatures, is the material used to make CPVC plumbing pipes. Hot and cold water, as well as other industrial liquids, are transported through these pipes.