Cyclopentane is a cycloalkane with the molecular formula C5H10. The CAS NO. is 287-92-3. It is a colorless transparent liquid, insoluble in water, and soluble in most organic solvents such as ethanol, ether, benzene, carbon tetrachloride, acetone, etc. As an important organic chemical raw material, cyclopentane is used to replace chlorofluorocarbons (CFCs),which have a damaging effect on the atmospheric ozone layer. It is used as a new blowing agent for the production of refrigerants and rigid polyurethane foams. It has been widely used in the production of fluorine-free refrigerators, freezers, cold storage, pipeline insulation, and other fields. As the deadline for banning ODS stipulated in Montreal and other conventions are approaching, CFCs and HCFCs products will soon be banned, and cyclopentane will surely become the protagonist in the field of polyurethane foaming agents.