Chinese name of chemical N-methylpyrrolidone Common name or trade name of chemical NMP English name of chemical N-methyl-2-pyrrolidone Molecular formula C5H9NO Molecular weight 99 Ingredients and content above 98 Hazardous ingredients CAS No. 870- 50-4 Physical and chemical properties Appearance and properties Appearance Liquid color Colorless and transparent Taste slightly amine odor Melting point (℃) -23℃ Relative density (water = 1) 1.0260 Boiling point (℃) 81-82 (1.33kpa) Relative vapor density ( Air = 1) Saturated vapor pressure (kpa) Heat of combustion (KJ/mol) Critical temperature (℃) Critical pressure (Mpa) Flash point (℃) 95℃ Explosion upper limit% (v/v) Ignition temperature (℃) Lower explosion limit % (v/v) Solubility in water, less than 100 mg/L (25°C) Others: more than 50 mass of n-hexane (25°C), more than 30 mass of acetone (25°C). Viscosity (25°C) 1.65mpa Logarithmic value of octanol/water partition coefficient Other characteristics Mainly used as an excellent solvent for aromatic hydrocarbon extraction, separation of butadiene or C5 fractions, natural gas desulfurization, acetylene concentration, and synthetic fiber extraction Silk. In addition, it can also be used in synthetic fuels, paints, pesticides, medicines, etc.