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Molekula

Molekula

Phthalic acid

SKU 38157787 CAS 88-99-3 C6H4(CO2H)2 MW 166.13 In stock Bulk quantities on request

Supplying 4,500+ customers in over 80 countries

ISO 9001:2015 & ISO 14001:2015 certified · Supplying laboratories and industry since 2000 · Listed pack sizes are a starting point — we manufacture, source and repack to the quantity you need

Phthalic acid is a white crystalline organic compound used in the production of plastics, resins, and dyes. It serves as a key intermediate in the synthesis of phthalate esters and other industrial chemicals. It is also used as an analytical and laboratory reagent and as a starting material for phthalimide, phenolphthalein, anthranilic acid and synthetic fragrances. CAS: 88-99-3, Molecular Formula: C6H4(CO2H)2, Molecular Weight: 166.13 g/mol, Storage: Ambient, Signal Word: Danger. Molekula supplies Phthalic acid from research to bulk quantities with full documentation and ISO 9001:2015 traceability.

Expect a response within hours Speak to a chemist: +44 (0) 3302 000333

Example image for illustration only. Other packaging and pack sizes are available.

Pricing & pack sizes

Pack sizes & pricing

These pack sizes aren't a limit. Molekula manufactures, sources and repacks to order — if you need 500 kg and only see 1 kg listed, . We quote from grams to multi-tonne.

Need a different size? Add the nearest pack and change the size in your basket — we price it at the same rate per unit.

  • 1 kg — $133.10 per pack

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Prices exclude VAT/sales tax and shipping.

Specifications

Property Value
Appearance White to off white powder
Melting Point 205 - 211°C
Heavy Metals (Pb) ≤ 0.01%
Iron (Fe) ≤ 0.005%
Chloridion ≥ 99.0%

Storage & handling

Property Value
Storage Temperature Ambient
Acidity Acid

Literature values

Published physical properties of the substance, not batch specifications.

Property Value
Appearance Colorless crystals
Melting Point 205 - 230 °C
Density 1.6 (relative, water = 1)
Solubility (other solvents) Soluble in alcohol; sparingly soluble in ether
Vapour Pressure 6.36 × 10⁻⁷ mmHg at 25 °C
pKa pKa = 2.76 (at 25 °C)
log P (octanol/water) 0.73

Source: PubChem CID 1017 (HSDB, Human Metabolome Database (HMDB), ICSC, DrugBank)

Identification

Property Value
SKU 38157787
CAS Number 88-99-3
IUPAC Name phthalic acid
EC Number 201-873-2
Molecular Formula C6H4(CO2H)2
Molecular Weight 166.13
Exact Mass 166.0266
SMILES C1=CC=C(C(=C1)C(=O)O)C(=O)O
InChIKey XNGIFLGASWRNHJ-UHFFFAOYSA-N
InChI InChI=1S/C8H6O4/c9-7(10)5-3-1-2-4-6(5)8(11)12/h1-4H,(H,9,10)(H,11,12)
PubChem CID 1017
REACH Code Y110
TSCA Listed Yes
HTS Code 29173970
Tariff Code 2917398590

Safety & GHS

Danger
  • GHS pictogram — Corrosive Corrosive GHS05
  • GHS pictogram — Serious Health Hazard Serious Health Hazard GHS08

Hazard statements

  • H318 Causes serious eye damage
  • H340 May cause genetic defects

Precautionary statements

  • P260 Do not breathe dust/fume/gas/mist/vapours/spray
  • P280 Wear protective gloves/protective clothing/eye protection/face protection
  • P305+351+338 IF IN EYES: Rinse with water for several minutes. Remove contact lenses if present and easy to do. Continue rinsing
  • P308+313 IF exposed or concerned: Get medical advice/attention
  • P337+313 If eye irritation persists get medical advice/attention

Documents

Safety Data Sheets (SDS)

Available in English, French, German, Italian, Spanish.

Certificate of Analysis (CoA) by batch

Enter a lot or batch number to retrieve the CoA for that specific batch. We can generate one from spec data if no PDF is on file.

Synonyms

  • 1,2-benzenedicarboxylic acid
  • Acide phtalique
  • benzene-1,2-dicarboxylic acid
  • hydron;phthalate
  • Kyselina ftalova
  • o-benzenedicarboxylic acid
  • o-dicarboxybenzene
  • o-phthalic acid
  • ortho-phthalic acid
  • Pathalic acid

Frequently asked questions

What is phthalic acid used for?

Phthalic acid is primarily used in the production of plasticizers, resins, and polyester compounds for industrial applications.

What is the chemical formula and molecular weight of phthalic acid?

The formula is C6H4(CO2H)2 with a molecular weight of 166.13 g/mol.

How should phthalic acid be stored?

It should be stored at ambient temperature, away from moisture and incompatible materials.

What grade of phthalic acid does Molekula supply?

Molekula supplies phthalic acid in technical grade; custom grades may be available upon request.

Can Molekula supply phthalic acid in bulk?

Yes, Molekula can supply phthalic acid in bulk quantities; please contact sales for details.

What documentation comes with a phthalic acid order?

Each order includes a Certificate of Analysis (CoA) and Safety Data Sheet (SDS) with the shipment.

Ready to order or need a custom pack?

Tell us the product, grade, and quantity — Molekula usually responds within one working day with pricing and lead time.

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