What Is CAS 104-76-7?
CAS 104-76-7 is 2-ethylhexanol, commonly abbreviated 2-EH. It is a branched, eight-carbon primary alcohol with the molecular formula C8H18O and the structural formula CH3CH2CH2CH2CH(CH2CH3)CH2OH, carrying an ethyl branch at the second carbon. The molecule has a chiral centre, and commercial material is normally supplied as the racemic mixture. 2-Ethylhexanol is a colourless liquid at room temperature with a mild characteristic odour, slightly soluble in water and freely soluble in most organic solvents.
Typical Specifications
Commercial 2-ethylhexanol is supplied at a purity of 99 % or higher. Suppliers offer pharmaceutical grade and industrial grade, and buyers should request the certificate of analysis to verify assay, water content, acidity and colour.
| Property | Typical Value |
|---|---|
| Chemical name | 2-Ethylhexanol (2-EH) |
| CAS number | 104-76-7 |
| Molecular formula | C8H18O |
| Molecular weight | 130.23 g/mol |
| Purity | 99 % min |
| Melting point | About -76 °C |
| Boiling point | About 184 °C |
| Density | About 0.833 g/cm3 |
| Flash point | About 85 °C |
| Appearance | Clear colourless liquid |
Use in Plasticizer Production
The largest application of 2-ethylhexanol is the production of plasticizers, which consumes roughly 80 to 85 % of global output. 2-EH is esterified with phthalic anhydride or terephthalic acid to make plasticizers such as DOP, DINP and DOTP. These esters soften rigid PVC into flexible products including wires, cables, flooring, films, coated fabrics and hoses. Because some phthalate plasticizers are restricted in toys, food-contact materials and medical devices in the EU and other markets, non-phthalate plasticizers made from 2-EH, such as DOTP, are gaining share.
Chemical Intermediate Applications
2-Ethylhexanol is converted into 2-ethylhexyl acrylate, a monomer for acrylic resins used in paints, adhesives and coatings. It is also used in the production of surfactants, dispersants, lubricant additives, emulsifiers and mineral processing reagents. These derivatives benefit from the branched structure of 2-EH, which improves low-temperature performance and hydrolysis resistance. The alcohol also acts as a coupling agent and esterification feedstock in the manufacture of esters for metalworking and industrial lubrication.
Plasticizers for flexible PVC - DOP, DINP and DOTP
2-Ethylhexyl acrylate for acrylic resins
Surfactants, emulsifiers and dispersants
Lubricant additives and ester base stocks
Use as a Solvent and in Speciality Applications
2-EH serves as a low-volatility solvent in coatings, inks and cleaning formulations, and as a dispersing agent in pigment concentrates. Smaller volumes are used in fragrances and cosmetics, in defoamers for latex systems, and in auxiliaries for paper sizing and textile processing. Its low evaporation rate makes it useful where slow drying and good levelling are required, and it helps keep open time long enough for uniform film formation in industrial coatings.
Quality, Safety and Regulatory Considerations
2-Ethylhexanol is a combustible liquid with a flash point near 85 °C. It is mildly irritating to skin and eyes, and vapours should not be inhaled. Storage should be in closed containers away from ignition sources and oxidisers. For the EU market, the substance and its derivatives must comply with REACH registration and applicable restrictions, and importers should verify the documentation package with their supplier before shipment.
Frequently Asked Questions
Q: What chemical is CAS 104-76-7?
CAS 104-76-7 is 2-ethylhexanol, a branched eight-carbon primary alcohol.
Q: What is 2-ethylhexanol used for?
2-Ethylhexanol is used mainly to produce plasticizers for flexible PVC, and as an intermediate for acrylates, surfactants and lubricant additives.
Q: What is the molecular formula of 2-ethylhexanol?
The molecular formula is C8H18O.
Q: What are the key properties of 2-EH?
The melting point is about -76 °C, the boiling point about 184 °C, and the density about 0.833 g/cm3.
Q: Is 2-ethylhexanol soluble in water?
2-Ethylhexanol is only slightly soluble in water but is freely soluble in most organic solvents.
Q: Why is 2-EH important for PVC?
2-EH is the alcohol used to make phthalate and non-phthalate plasticizers that give flexible PVC its softness and flexibility.