Dioctyl terephthalate (bis(2-ethylhexyl) benzene-1,4-dicarboxylate or Di(2-ethylhexyl) terephthalate), commonly abbreviated DOTP or DEHT, is an organic compound with the formula C6H4(CO2 C8H17)2. It is a non-phthalate plasticiser, being the diester of terephthalic acid and the branched-chain 2-ethylhexanol. This colorless viscous liquid used for softening PVC plastics is known for chemical similarity to general purpose phthalates such as DEHP and DINP, but without any negative regulatory pressure. It possesses very good plasticizing properties and may be used as a direct replacement for DEHP and DINP in many applications.
| Product name | Dioctyl terephthalate |
| Chemical formula | C24h38o4 |
| Molecular weight | 390.5561 |
| CAS.NO | 6422-86-2 |
| EINECS | 229-176-9 |
| Flash point | 230 °f |
| Melting point | – 48 °C |
| Boiling point | 400 °C (lit.) |
| Water-soluble | Insoluble |
| Vapor pressure | 1 mm hg (217 °C) |
| Solubility | Aqueous base (slightly) |
| Stability | Hygroscopic |
| Appearance | Liquid |
| Color | Clear colorless |
| Physico-chemical property | Colorless or yellowish oily liquid. It is almost insoluble in water, and the solubility in water is 0.4% at 20 °C. |
| Product application | As a plasticizer, it is widely used in soft pvc and cable materials. It has the characteristics of low volatility, low tenderness, good softness, water resistance, oil resistance, etc. |