Dioctyl terephthalate
 | |
| Names | |
|---|---|
| IUPAC name
Bis(2-ethylhexyl) benzene-1,4-dicarboxylate | |
| Other names
Dioctyl Terephthalate; Bis(2-ethylhexyl) terephthalate; Di(ethylhexyl) terephthalate; 1,4-Benzenedicarboxylic acid bis(2-ethylhexyl) ester | |
| Identifiers | |
6422-86-2  | |
| Abbreviations | DOTP, DEHT |
| ChemSpider | 21471 |
| EC Number | 229-176-9 |
| Jmol interactive 3D | Image |
| MeSH | C053316 |
| PubChem | 22932 |
| |
| |
| Properties | |
| C24H38O4 | |
| Molar mass | 390.56 g·mol−1 |
| Appearance | Clear viscous liquid |
| Density | 0.984 g/mL |
| Boiling point | 400 °C (752 °F; 673 K) |
| Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | |
| Infobox references | |
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.
Production
One method of manufacture entails the transesterification of dimethyl terephthalate with 2-ethylhexanol:
- C6H4(CO)2(OCH3)2 + 2 C8H17OH → C6H4(CO2 C8H17)2 + 2CH3OH
A second method of manufacture is a direct esterification of terephthalic acid with 2-ethylhexanol:
- C6H4(CO2H)2 + 2 C8H17OH → C6H4(CO2 C8H17)2 + 2H2O
Use
DOTP is a general purpose plasticizer that is considered safer than ortho-phthalate plasticizers due to its excellent toxicological profile. The terephthalates exhibit none of the peroxisome proliferation of liver enzymes that some ortho-phthalates have shown in several studies.[1] It has uses in applications like extrusion, calendering, injection molding, rotational molding, dip molding, slush molding and coating.[2]
Alternative plasticizers
There are several alternative plasticizers offering similar technical properties to DOTP. These alternatives include phthalates such as DINP, DOP, DPHP, DIDP as well as non-phthalates such as DINCH and citrate esters.
References
- ↑ OECD SIDS Initial Assessment Report for SIAM 17 (2003)
- ↑ http://www.sasaplus88.com/en/U_Chemi_omP.asp