Description and features

Rostabil DPDP (Isodecyl diphenyl phosphite) is a clear liquid which has C22H31O3P as chemical formula. It it used as a color and processing stabilizer in polycarbonate, polyurethanes, ABS polymers, coatings and it is also used as a secondary stabilizer in PVC.

Isodecyl diphenyl phosphite is also known as Diphenyl isodecyl phosphite and phosphorous acid, 8-methylnonyl diphenyl ester.

Shipment Info

Europe: Provided Rostabil DPDP is on stock in our local warehouses our lead time is about one week if delivered in 200 KG steel drums.

United States, Canada, South America, South Africa and other markets can also be served, please contact our sales department for more details.

This substance (CAS: 26544-23-0) has been registered (FULL) under REACH (EC) 1907/2006.

Product Identification

CAS number 26544-23-0
EC number 247-777-4
HS code 2920 90 85
IUPAC name2-methylnonyl diphenyl phosphite


Appearance Clear liquid
Acid Value ≤0.0 1 mg KOH/g
Colour ≤100 Hazen


Available packaging: 200 KG steel drums.
Special packaging is available on request.


Store Isodecyl diphenyl phosphite in a cool, dry and well-ventilated area and in line with legal requirements.
Keep DPDP away from heat sources and oxidizing agents.


A Material Safety Data Sheets (MSDS) is available for Rostabil DPDP and all other products supplied by Vesta Chemicals BV.

An MSDS describes the hazards of a product and explains how a product can be safely handled, used and stored. Besides it provides important regulatory and emergency response information for the purchased product.

Molecular and structural information

Molecular formula C22H31O3P
Molecular weight 374.45 g/mol
Structural formula 26544-23-0

Physicochemical information

Boiling point 435.74 °C
Density1.03 – 1.05 @ 20°C g/cm3
Flash point 130.0 ºC
Melting point 154.75 °C
Partition coefficient (log Pow) 8.52
Refractive index 1.521 – 1.527 @ 20°C
Solubility in water Insoluble (< 0.1 mg/l)
Specific gravity 1.020 – 1.036 g/m3 (25 °C/15 °C)
Vapour pressure 2.07E-09 Pa @ 25°C
Isodecyl diphenyl phosphite | CAS: 26544-23-0 | Disclaimer. This information is supplied solely for informational purposes and Vesta Chemicals bv makes no guarantees or warranties, either expressed or implied, with respect to the accuracy and use of this data. All product warranties and guarantees shall be governed by the Standard Terms of Sale. Nothing in this document is legal advice or is a substitute for competent legal advice.