Terephthalic acid

Terephthalic acid
Skeletal formula
Ball-and-stick model of the terephthalic acid molecule
Names
Preferred IUPAC name
Benzene-1,4-dicarboxylic acid
Other names
Terephthalic acid
para-Phthalic acid
TPA
PTA
BDC
Identifiers
3D model (JSmol)
3DMet
1909333
ChEBI
ChEMBL
ChemSpider
ECHA InfoCard 100.002.573 Edit this at Wikidata
EC Number
  • 202-830-0
50561
KEGG
RTECS number
  • WZ0875000
UNII
  • InChI=1S/C8H6O4/c9-7(10)5-1-2-6(4-3-5)8(11)12/h1-4H,(H,9,10)(H,11,12) checkY
    Key: KKEYFWRCBNTPAC-UHFFFAOYSA-N checkY
  • InChI=1/C8H6O4/c9-7(10)5-1-2-6(4-3-5)8(11)12/h1-4H,(H,9,10)(H,11,12)
    Key: KKEYFWRCBNTPAC-UHFFFAOYAF
  • O=C(O)c1ccc(C(O)=O)cc1
Properties
C8H6O4
Molar mass 166.132 g·mol−1
Appearance White crystals or powder
Density 1.519 g/cm3[1]
Melting point 300 °C (572 °F; 573 K) Sublimes[1]
Boiling point Decomposes
0.065 g/L at 25 °C[2]
Solubility polar organic solvents aqueous base
Acidity (pKa) 3.54, 4.34[3]
−83.5×10−6 cm3/mol[4]
Structure
2.6D [5]
Thermochemistry[6]
−816.1 kJ/mol
Hazards
GHS labelling:
GHS07: Exclamation mark
Warning
H315, H319, H335
P261, P264, P271, P280, P302+P352, P304+P340, P305+P351+P338, P312, P321, P332+P313, P337+P313, P362, P403+P233, P405, P501
Flash point 260 °C (500 °F; 533 K)[9]
496 °C (925 °F; 769 K)[9]
10 mg/m3[7] (STEL)
Lethal dose or concentration (LD, LC):
>1 g/kg (oral, mouse)[8]
Safety data sheet (SDS) MSDS sheet
Related compounds
Phthalic acid
Isophthalic acid
Benzoic acid
p-Toluic acid
Related compounds
 p-Xylene
Polyethylene terephthalate
Dimethyl terephthalate
Supplementary data page
Terephthalic acid (data page)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
☒N verify (what is checkY☒N ?)

Terephthalic acid is an organic compound with formula C6H4(CO2H)2. This white solid is a commodity chemical, used principally as a precursor to the polyester PET, used to make clothing and plastic bottles. Several million tons are produced annually.[8] The common name is derived from the turpentine-producing tree Pistacia terebinthus and phthalic acid.

Terephthalic acid is also used in the production of PBT plastic (polybutylene terephthalate).[10]

  1. ^ a b Haynes, p. 3.492
  2. ^ Haynes, p. 5.163
  3. ^ Haynes, p. 5.96
  4. ^ Haynes, p. 3.579
  5. ^ Karthikeyan, N.; Joseph Prince, J.; Ramalingam, S.; Periandy, S. (2015). "Electronic [UV–Visible] and vibrational [FT-IR, FT-Raman] investigation and NMR–mass spectroscopic analysis of terephthalic acid using quantum Gaussian calculations". Spectrochimica Acta Part A. 139: 229–242. Bibcode:2015AcSpA.139..229K. doi:10.1016/j.saa.2014.11.112. PMID 25561302.
  6. ^ Haynes, p. 5.37
  7. ^ Haynes, p. 16.42
  8. ^ a b Cite error: The named reference Ullmann was invoked but never defined (see the help page).
  9. ^ a b Haynes, p. 16.29
  10. ^ "Polybutylene Terephthalate (PBT) Material Guide & Properties Info". omnexus.specialchem.com. Archived from the original on 2023-11-24. Retrieved 2023-11-24.