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Diethyl phthalate


Linear Formula:
CAS Number:
Molecular Weight:
EC Number:
MDL number:
PubChem Substance ID:

Quality Level

vapor density

7.66 (vs air)

vapor pressure

1 mmHg ( 100 °C)





autoignition temp.

854 °F

expl. lim.

0.75 %, 187 °F


≤0.18% water


APHA: ≤15

refractive index

n20/D 1.502 (lit.)


298-299 °C (lit.)


−3 °C (lit.)


1.12 g/mL at 25 °C (lit.)

SMILES string




InChI key


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General description

Diethyl phthalate (DEP) is a phthalic anhydride ester (PAE) that is commonly used as a solvent in cosmetics and also as a plasticizer.


Diethyl phthalate can be used as a solvent for the antimony reduction of aluminum chloride-phosphorus trichloride-alkyl chloride complexes to form the corresponding alkylphosphonous dichlorides. It can undergo condensation with o-phenylenediamine in the presence of sodium hydride to form dibenzo (b,f)(1,4)diazocine-6,11(5H, 12H)-dione.


5 mL in glass bottle
1, 4 L in poly bottle
100 mL in poly bottle

Other Notes


Storage Class Code

10 - Combustible liquids



Flash Point(F)

338.0 °F - closed cup

Flash Point(C)

170 °C - closed cup

Personal Protective Equipment

dust mask type N95 (US), Eyeshields, Gloves

Certificate of Analysis

Enter Lot Number to search for Certificate of Analysis (COA).

Certificate of Origin

Enter Lot Number to search for Certificate of Origin (COO).

  1. How does the storage temperature relate to shipping conditions?

    The storage conditions that a Sigma-Aldrich catalog and label recommend for products are deliberately conservative. For many products, long-term storage at low temperatures will increase the time during which they are expected to remain in specification and therefore are labeled accordingly. Where short-term storage, shipping time frame, or exposure to conditions other than those recommended for long-term storage will not affect product quality, Sigma-Aldrich will ship at ambient temperature. The products sensitive to short-term exposure to conditions other than their recommended long-term storage are shipped on wet or dry ice. Ambient temperature shipping helps to control shipping costs for our customers. At any time, our customers can request wet- or dry-ice shipment, but the special handling is at customer expense if our product history indicates that the product is stable for regular shipment. See Shipping and Storage for more information.

  2. Which document(s) contains shelf-life or expiration date information for a given product?

    If available for a given product, the recommended re-test date or the expiration date can be found on the Certificate of Analysis.

  3. How do I get lot-specific information or a Certificate of Analysis?

    The lot specific COA document can be found by entering the lot number above under the "Documents" section.

  4. How do I find price and availability?

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  5. What is the Department of Transportation shipping information for this product?

    Transportation information can be found in Section 14 of the product's (M)SDS.To access the shipping information for this material, use the link on the product detail page for the product. 

  6. I want to use Product 524972, Diethyl phthalate in cell culture or tissue culture.  In what solvent can I dilute diethyl phthlate?

    Product 524972, Diethyl phthalate, is soluble in ethanol to 0.1 M.  Lee, S.-M., et al., Dibutyl Phthalate Biodegradation by the White Rot Fungus, Polyporus brumalis.  Biotechnology and Bioengineering, 97(6), 1516-1522 (2007).

  7. My question is not addressed here, how can I contact Technical Service for assistance?

    Ask a Scientist here.

Diazocine chemistry. V. Synthesis and rearrangement of dibenzo [b, f][1, 4] diazocine-6, 11 (5H, 12H)-dione.
Paudler W W and Zeiler A G
The Journal of Organic Chemistry, 34(7), 2138-2140 (1969)
The synthesis of alkylphosphonous dichlorides from aluminum chloride?phosphorus trichloride?alkyl chloride complexes.
Perry B J, et al.
Canadian Journal of Chemistry, 41(9), 2299-2302 (1963)
Raphael J Witorsch et al.
Critical reviews in toxicology, 40 Suppl 3, 1-30 (2010-10-12)
This article reviews laboratory and epidemiological research into the endocrine disruptive effects of components of personal care products, namely, phthalate esters, parabens, ultraviolet (UV) filters, polycyclic musks, and antimicrobials. High doses of phthalates in utero can produce “phthalate syndrome,” demasculinizing
Kashappa-Goud H Desai et al.
Journal of controlled release : official journal of the Controlled Release Society, 165(1), 62-74 (2012-10-30)
Herein, we describe the detailed development of a simple and effective method to microencapsulate vaccine antigens in poly(lactic-co-glycolic acid) (PLGA) by simple mixing of preformed active self-microencapsulating (SM) PLGA microspheres in a low concentration aqueous antigen solution at modest temperature
A M Api
Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association, 39(2), 97-108 (2001-03-27)
Diethyl phthalate (DEP; CAS No. 84-66-2) has many industrial uses, as a solvent and vehicle for fragrance and cosmetic ingredients and subsequent skin contact. This review focuses on its safety in use as a solvent and vehicle for fragrance and

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