Definition and Uses :
Nonylphenols are a family of closely related organic compounds called alkylphenols. They are used in the production of antioxidants, lubricating oil additives, laundry and dishwashing detergents, emulsifiers, and solubilizers. These compounds are also present in nonionic surfactants such as alkylphenol ethoxylates and nonylphenol ethoxylates used in detergents, paints, pesticides, personal care products, and plastics. Nonylphenol has attracted attention due to its potential role as an endocrine disruptor and xenoestrogen due to its prevalence in the environment and its ability to act with estrogen-like activity. Estrogenicity and biodegradation are dependent on the nonyl side chain.
Nonylphenols fall into the general chemical category of alkylphenols. The structure of the NPs can vary. The nonyl group can be attached to the phenol ring at various positions, usually the 4- and to a lesser extent the 2-positions, and can be branched or linear. A branched nonylphenol, 4-nonylphenol, is the most widely produced and marketed nonylphenol. A mixture of nonylphenol isomers is a pale yellow liquid, but the pure compounds are colorless. Nonylphenols are moderately soluble in water but soluble in alcohol.
Nonylphenol originates from the environmental degradation of nonylphenol ethoxylates, metabolites in commercial detergents called alkylphenol ethoxylates. NPEs are a pale-orange liquid. Nonylphenol ethoxylates are non-ionic in water, meaning they have no charge. This property makes them useful as detergents, cleaners, emulsifiers, and a variety of other applications. They are amphipathic, meaning they have both hydrophilic and hydrophobic properties, which allows them to surround and insulate nonpolar substances such as oils and greases from water.