Definition and Usage Areas of Nonylphenols
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 for 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 NPs can vary. The nonyl group can be attached to the phenol ring at various positions, usually the 4- and to a lesser extent 2-positions, and may be branched or linear. A branched nonylphenol, 4-nonylphenol, is the most widely produced and marketed nonylphenol. The mixture of nonylphenol isomers is a pale yellow liquid, but pure compounds are colorless. Nonylphenols are moderately soluble in water but soluble in alcohol.
Nonylphenol originates from the environmental degradation of nonylphenol ethoxylates, which are metabolites in commercial detergents called alkylphenol ethoxylates. NPEs are a clear to light orange-colored liquid. Nonylphenol ethoxylates are non-ionic in water; this means they have no payload. Because of this property, they are used as detergents, cleaners, emulsifiers and various applications. They are amphipathic, meaning they have hydrophilic and hydrophobic properties; this allows them to surround non-polar substances such as oil and grease and insulate them from water.
- Nonylphenol is used in the manufacture of antioxidants, lubricating oil additives, laundry and dishwashing detergents, emulsifiers and solubilizers.
- It can also be used to produce tris (4-nonyl-phenyl) phosphide (TNPP), an antioxidant used to protect polymers such as rubber, vinyl polymers, polyolefins and polystyrene,
- In addition, it is a stabilizer in plastic food packaging. Barium and calcium salts of nonylphenol are also used as heat stabilizers for polyvinyl chloride (PVC).
- Nonylphenol is also often used as an intermediate in the manufacture of non-ionic surfactants nonylphenol exoxylates, which are used in detergents, paints, pesticides, personal care products, and plastics.
- Nonylphenol and nonylphenol ethoxylates are only used as components of household detergents outside of Europe.