isononyl

Isononyl is a branched nine-carbon alkyl substituent derived from isononyl alcohol, typically 3,5-dimethylhexan-1-ol. In chemical naming, the term is used to designate compounds that incorporate this specific isomeric alkyl group, most commonly as esters or plasticizers.

The isononyl group appears in a variety of industrial compounds, including isononyl esters such as isononyl acrylate and isononyl methacrylate, as well as diisononyl phthalate (DINP). DINP, a widely used plasticizer for polyvinyl chloride and related polymers, exemplifies the role of the isononyl moiety in imparting flexibility and workability to materials like coatings, adhesives, and sealants. In cosmetics and personal care, isononyl esters serve as emollients or solvent components; examples include isononyl isononanoate and related derivatives.

Production and applications: Isononyl esters are typically produced by esterification or transesterification, reacting isononyl alcohol with suitable acids (such as phthalic anhydride for DINP, or acrylic/methacrylic acids for acrylates and methacrylates). The resulting compounds are used to modify texture, flexibility, and skin feel in consumer products, as well as to adjust mechanical properties in polymer systems.

Properties: Compounds containing the isononyl group tend to be nonpolar and hydrophobic, with low water solubility. Their physical properties—such as volatility and plasticizing efficiency—depend on the overall molecular structure and the counter-ester group.

Safety and regulation: Some isononyl-containing phthalates (e.g., DINP) are subject to regulatory review and usage restrictions in certain applications and regions due to health and environmental concerns associated with phthalates.

See also: isononyl alcohol; isononyl acrylate; isononyl methacrylate; diisononyl phthalate.