Dibutyl phthalate (DBP)

Dibutyl phthalate (DBP) is an organic compound which is commonly used as a plasticizer because of its low toxicity and wide liquid range. With the chemical formula C6H4(CO2C4H9)2, it is a colorless oil, although commercial samples are often yellow. 
DBP is produced by the reaction of n-butanol with phthalic anhydride.[3] DBP is an important plasticizer that enhances the utility of some major engineering plastics, such as PVC. Such modified PVC is widely used in plumbing for carrying sewerage and other corrosive materials.

Properties
Chemical formula C16H22O4
Molar mass 278.348 g·mol−1
Appearance Colorless liquid
Odor Aromatic
Density 1.05 g/cm3 at 20 °C
< Melting point −35 °C (−31 °F; 238 K)
Boiling point 340 °C (644 °F; 613 K)
Solubility in water 13 mg/L (25 °C)
log P 4.72
Vapor pressure 0.00007 mmHg (20 °C)[1]
Magnetic susceptibility (χ) -175.1·10−6 cm3/mol