Terephthalic acid
CAS 100-21-0
EC 202-830-0
Formula C8H6O4
MW 166.13 g/mol
Organic Acids Plastics & PolymersPrinting & PackagingTextile, Leather & PaperPersonal Care & CosmeticsFood & Nutrition Polymerization InitiationCatalysisPreservation & BiocidepH Regulation & Buffering
Description
Terephthalic acid (CAS 100-21-0), commonly abbreviated as TPA and also known as p-phthalic acid, is a benzene dicarboxylic acid registered under EC 202-830-0. It carries no E-code designation and is classified under HS code 29173990 for customs purposes.
In polyester production, TPA reacts with ethylene glycol through polycondensation to form PET, the backbone of packaging films, bottles, and synthetic textile fibres. It also functions as a pH buffer and mild preservative in select formulations, where its dicarboxylic structure enables controlled proton donation across a defined pH range.
TPA is sourced in technical and polymer grades as a crystalline powder, with supply compliant with REACH registration requirements for the European market. Packaging is available in multi-layer bags and bulk formats suited to industrial volumes. Buyers should confirm grade specification against intended application, particularly where food-contact or cosmetic compliance is required.
In polyester production, TPA reacts with ethylene glycol through polycondensation to form PET, the backbone of packaging films, bottles, and synthetic textile fibres. It also functions as a pH buffer and mild preservative in select formulations, where its dicarboxylic structure enables controlled proton donation across a defined pH range.
TPA is sourced in technical and polymer grades as a crystalline powder, with supply compliant with REACH registration requirements for the European market. Packaging is available in multi-layer bags and bulk formats suited to industrial volumes. Buyers should confirm grade specification against intended application, particularly where food-contact or cosmetic compliance is required.
Physical Properties
| Melting Point | 402 °C (sublm) |
| Boiling Point | 214.32°C (rough estimate) |
| Density | 1.51 g/cm³ |
| Flash Point | 260°C |
| Appearance | TPA is a white crystalline solid. |
| Color | White |
| Form | Crystalline Powder |
| Water Solubility | slightly soluble in water (0,017 g/L at 25°C) |
| Vapor Pressure | <0.01 mm Hg ( 20 °C) |
| Refractive Index | 1.5100 (estimate) |
| pH | 3.36(1 mM solution);2.79(10 mM solution);2.26(100 mM solution) |
| Log P | 2 at 25℃ |
Safety & Handling (Learn More)
Danger GHS07 GHS08
H
H302H315H316H319H320H335H361H372H373
P
P203P260P261P264P270P271P280P318P319P321P330P405P501P264+P265P301+P317P302+P352P304+P340P332+P317P337+P317P362+P364P403+P233P305+P351+P338
Trade & Regulatory
| HS Code | 29173990 |
| Storage Class | 11 - Combustible Solids |
| WGK (Germany) | 3 |
Other Names
PTAp-phthalic acidTPAWR 16262TERPHTHALIC ACID
Related Products
Raw Materials
Derivatives
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