Diisononyl adipate (DINA)

Diisononyl adipate (DINA) is a mixture of isomeric compounds that have the same molecular formula and largely the same structure, but differ in the detailed configuration. For industrial applications of the substance mixture, however, these differences are negligible, so that diisononyl adipate is generally spoken of as a single substance.

The general structure of the compounds is expressed in the alternative designation adipic acid diisononyl ester. In the center of the molecule is a residue of adipic acid, which has been esterified with two alcoholic compounds with conversion of the two terminal carboxylic acid groups. These are branched or unbranched hydrocarbons with nine carbon atoms.

Under normal conditions, diisononyl adipate (DINA) is a colorless liquid with a faint intrinsic odor. The mixture of substances has an oily consistency and is barely volatile. Diisononyl adipate is practically insoluble in water, due to its lower density it floats on contact with water. In contrast, the mixture is readily soluble in organic solvents. Diisononyl adipate is very temperature resistant. It only changes into the gaseous state at temperatures above 232 °C and does not solidify until a temperature of -65 °C is reached.

When stored as intended, diisononyl adipate (DINA) is a chemically very stable mixture of substances. However, if heated to the boiling point, the substances in the mixture decompose with the risk of explosion and a significant increase in pressure in closed containers. Diisononyl adipate (DINA) is flammable, however it is difficult to ignite. Various gases that are irritants and hazardous to health are produced during the thermal decomposition or combustion of the mixture of substances. Among others, large amounts of carbon monoxide and carbon dioxide can be released.

Diisononyl adipate (DINA) may cause mild skin, eye and respiratory tract irritation upon direct contact with the liquid and inhalation of vapors and aerosols. Affected parts of the body should be cleaned thoroughly with water as far as possible. However, according to the GHS classification, diisononyl adipate is not a hazardous substance and is not subject to any special transport regulations. However, the mixture of substances is considered to be slightly hazardous to water and potentially dangerous for aquatic organisms. A penetration into the environment is therefore to be avoided. Inform local authorities if diisononyl adipate leaks into soil, waterways or sewers.