Methylhydroquinone (THQ)

1. Basic Information

Chemical Name: 2-Methylhydroquinone (o-Methyl-p-benzenediol / 2,5-Dihydroxytoluene)

Synonyms: Toluhydroquinone, THQ, 2-Methyl-1,4-benzenediol

CAS No.: 95-71-6

Molecular Formula: C₇H₈O₂

Molecular Weight: 124.14 g/mol

EINECS No.: 202-443-7

2. Product Specifications

- Appearance: White or off-white crystalline powder

- Assay: ≥99.0%

- Melting Point: 126.0–130.0°C

- Moisture: ≤0.1%

- Residue on Ignition: ≤0.05%

 3. Physical & Chemical Properties

Appearance: White or off-white crystalline powder with slight characteristic odor

Melting Point: 126.0–130.0°C

Boiling Point: 285°C (atmospheric pressure)

Density: ~1.22 g/cm³ at 20°C

Solubility: Slightly soluble in water, freely soluble in ethanol, ether, benzene, etc.

Stability: Air-sensitive, discolors on exposure to light; exhibits reducing and antioxidant properties

4. Main Applications

- Serves as a highly effective polymerization inhibitor for unsaturated polyester resins and vinyl monomers, with low dosage and long-lasting inhibition effect

- Acts as an antioxidant for stabilizing non-edible fats and oils such as fatty acid esters and linseed oil

- Inhibits peroxide formation in ethers, chlorinated hydrocarbons, and ethyl cellulose

- Serves as an intermediate in the synthesis of dyes, pharmaceuticals, plasticizers, and other stabilizers

- An upgraded alternative to hydroquinone, with no product contamination and excellent thermal stability

5. Packaging & Storage

Packaging: 25kg net fiber drum lined with polyethylene plastic bag (or 1kg aluminum foil bag)

Storage: Store sealed in a cool, dry, well-ventilated warehouse; protect from light, heat, fire, and strong oxidizing agents

Shelf Life: 24 months

6. Safety Information

- Irritating to skin and eyes; wear safety goggles and chemical-resistant gloves during handling

- Avoid inhaling dust; ensure adequate ventilation in the working area

- Flammable; strictly prohibit mixing or transporting with strong oxidizing agents

- In case of accidental contact, rinse the affected area with plenty of water immediately and seek medical attention if necessary