Terephthalic acid
Description
Terephthalic acid (CAS 100-21-0), commonly abbreviated as PTA in commodity markets, is a dicarboxylic acid that serves as a primary monomer in the production of polyester resins and fibers.
Its role as a building block in high-volume polymer synthesis makes it one of the most traded industrial organic acids globally. This chemical is the foundational raw material for polyethylene terephthalate.
It is consumed in enormous volumes for beverage bottles, food packaging films, and textile-grade polyester fiber. In engineering plastics, it contributes to polybutylene terephthalate formulations.
These formulations are used in automotive and electrical components. Coatings and adhesives manufacturers use the acid as a crosslinking monomer in alkyd and powder coating resins.
Controlled molecular architecture is critical to end-product performance in these sectors. Specialty applications include use as a catalyst precursor and pH-buffering agent in select industrial process formulations.
The material is supplied as a white powder or fine crystalline solid. Purified terephthalic acid is the dominant commercial specification for polymer-grade applications in the global market.
Technical and industrial grades are available for non-fiber and non-packaging end uses. Packaging options typically range from multi-wall bags to bulk supersacks for industrial logistics.
This reflects its high-volume commodity status across the chemical supply chain. All batches are tested to ensure they meet rigorous industrial and chemical manufacturing requirements.
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)
Trade & Regulatory
| HS Code | 29173990 |
| Storage Class | 11 - Combustible Solids |
| WGK (Germany) | 3 |
Documentation
Other Names
para-phthalic acid|para-benzenedicarboxylic acid|P-Phthelic acid|p-phthalic acid|p-dicarboxybenzene|p-benzenedicarboxylic acid|benzene-p-dicarboxylic acid|benzene-1,4-dicarboxylic acid|PTA
Related Products
Need a chemical? Get a quote within 24 hours.