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. 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.

 

 

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