Di-isononyl phthalate (DINP) is a mixture of isomers that have alkyl chains from 8 to 10 carbons long, but the largest portion of the mixture have chains composed of 9-carbons.
Around 95% of DINP is used in PVC as a plasticiser. More than half of the remaining 5% is used in the production of polymers other than PVC (e.g. rubbers). The remaining DINP is used in non-polymer applications including anti-corrosion paints, anti-fouling paints, lacquers, inks, adhesives and sealants.
Source: based on the GreenFacts Digest on phthalates
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Di-isononyl phthalate (DINP) molecular formula C26H42O4