Diisopropanolamine (DIPA) is an organic chemical compound belonging to the alkanolamine family. It is a derivative of Isopropanolamine, characterized by the presence of two hydroxyl groups and one amine group. Due to its structure, DIPA is used as a chemical intermediate and a pH regulator in various industrial applications, including cosmetics. It typically appears as a viscous, colorless or slightly yellowish liquid with a faint ammonia-like odor.

Chemical Composition and Structure

The chemical formula of Diisopropanolamine is C₆H₁₅NO₂. Its molecular structure consists of two isopropyl groups attached to an amine group (-NH) and two hydroxyl groups (-OH). The presence of two hydroxyl groups makes DIPA highly soluble in water and polar solvents, while the amine group gives it basic properties, making it an effective pH regulator and buffering agent in a variety of formulations.

Physical Properties

It appears as a viscous, colorless or slightly yellowish liquid with a boiling point of about 243°C. It is miscible with water, alcohols, and other polar solvents due to the presence of two hydroxyl groups. DIPA has a typically basic pH, ranging from 9 to 11 in aqueous solutions, making it an effective buffering agent. Its density is around 1.02 g/cm³ at 25°C. It is stable at room temperature but can react with strong oxidizers and acids.

Production Process

Diisopropanolamine is produced industrially via a reaction between propylene oxide and ammonia, similar to the production of Isopropanolamine but with a different stoichiometric ratio. Several alkanolamines are formed during this reaction, including DIPA, which is separated through fractional distillation. The process is optimized to ensure the purity required for use in industries with high standards, such as cosmetics.

Applications

• Cosmetics: Diisopropanolamine is widely used as a pH regulator and emulsifier in cosmetic formulations. It is particularly valued in products like shampoos, conditioners, and skin creams, where its ability to stabilize emulsions and maintain stable pH is essential for product quality.

INCI Functions:

Buffering agent. It is an iingredient that can bring an alkaline or acid solution to a certain pH level and prevent it from changing, in practice a pH stabiliser that can effectively resist instability and pH change.

Cosmetic safety

Restricted cosmetic ingredient as II/411 a Relevant Item in the Annexes of the European Cosmetics Regulation 1223/2009. Substance or ingredient reported:  Secondary alkyl- and alkanolamines and their salts

Environmental and Safety Considerations
Diisopropanolamine is generally regarded as safe for use in cosmetics, but like all chemical substances, it must be used according to established guidelines to avoid skin irritations or allergic reactions, especially in individuals with sensitive skin. Higher concentrations can increase the risk of irritation, so controlled levels in formulations are important. Environmentally, DIPA is biodegradable and does not tend to accumulate in ecosystems, but it is essential to ensure that it is produced and disposed of in a sustainable manner.

Molecular Formula  C₆H₁₅NO₂

Molecular Weight  133.19 g/mol

CAS     110-97-4

UNII    0W44HYL8T5

EC Number  203-820-9

CHEMBL2106303

CHEBI:143266

DTXSID8020179

Nikkaji   J5.102K

Synonyms:

1,1'-Iminodipropan-2-ol

Bis(2-hydroxypropyl)amine

References__________________________________________________________________________

Writer, C. I. R. (2024). Safety Assessment of Diisopropanolamine, Triisopropanolamine, Isopropanolamine, and Mixed lsopropanolamines as Used in Cosmetics. The Expert Panel for Cosmetic Ingredient Safety members are: Chair, Wilma F. Bergfeld, M.D., F.A.C.P.; Donald V. Belsito, M.D.; David E. Cohen, M.D.; Curtis D. Klaassen, Ph.D.; Allan E. Rettie, Ph.D.; David Ross, Ph.D.; Thomas J. Slaga, Ph.D.;Paul W. Snyder, D.V.M., Ph.D.; and Susan C. Tilton, Ph.D. The Cosmetic Ingredient Review (CIR) Executive Director is Bart Heldreth, Ph.D., and the Senior Director is Monice Fiume, M.B.A. This safety assessment was prepared by Preethi Raj, M.Sc., Senior Scientific Analyst/Writer, CIR.

Rind T, Oiso N, Hirao A, Kawada A. Allergic Contact Dermatitis with Diffuse Erythematous Reaction from Diisopropanolamine in a Compress. Case Rep Dermatol. 2010 Apr 23;2(1):50-54. doi: 10.1159/000313430.

Abstract. Compresses containing a nonsteroidal antiinflammatory drug (NSAID) are commonly used in Japan. However, this treatment may induce both allergic and photoallergic contact dermatitis from the NSAIDs and their ingredients. Here, we describe a case of allergic contact dermatitis with diffuse erythematous reaction due to diisopropanolamine in the applied compress. The absorption of diisopropanolamine might have been enhanced by the occlusive condition.

Ramli, R. M., Chong, F. K., Omar, A. A., & Murugesan, T. (2015). Performance of surfactant assisted synthesis of Fe/TiO2 on the photodegradation of diisopropanolamine. CLEAN–Soil, Air, Water, 43(5), 690-697.

Abstract. Titanium dioxide, TiO2 nanoparticles were synthesized via microemulsion method employing Triton X-100 as the surfactant. Heat treatment was used to remove residual organic entities and also to produce anatase TiO2. Iron (Fe) was incorporated by wet impregnation into the TiO2 nanoparticles in order to shift the active region of the photocatalyst from UV into visible region. The Fe/TiO2 photocatalyst was characterized and their performance on the degradation of aqueous diisopropanolamine solution was compared with the commercial TiO2. The optimum conditions for the photodegradation of aqueous diisopropanolamine were found to be at 0.2 wt% of Fe. The present synthesized Fe/TiO2 photocatalyst showed an improved performance over the commercial TiO2 on the COD removal.

Khamaruddin, P. F., Bustam, M. A., & Omar, A. A. (2011, June). Using Fenton’s reagents for the degradation of diisopropanolamine: effect of temperature and pH. In International Conference on Environment and Industrial Innovation IPCBEE (Vol. 12, pp. 12-17).