Maleic anhydride (CAS 108-31-6) is a versatile chemical intermediate used in plastics, coatings, agriculture, and water treatment. This quick guide covers its key applications, market outlook, safety, and sourcing.

What Is Maleic Anhydride?
Maleic anhydride (C₄H₂O₃) is a white crystalline solid with a pungent odor. It is produced mainly by n-butane oxidation and is highly reactive due to its anhydride group and double bond.

Main Applications

• Unsaturated polyester resins (UPR): Largest use, over 50% of global demand.

• Alkyd resins: For paints, varnishes, and industrial coatings.

• Copolymers and compatibilizers: Improve polymer blending and adhesion.

• Lubricant additives: Succinimides for engine oils.

• Agrochemicals: Maleic hydrazide, malathion.

• Other: BDO/THF, fumaric acid, paper sizing, water treatment.

Market Outlook
Global maleic anhydride market was valued at ~USD 3.4–4.0 billion in 2025 and is projected to reach ~USD 5 billion by 2034, growing at 4–7% CAGR. Asia-Pacific dominates with ~70% consumption, led by China.

Safety and Handling
Maleic anhydride is corrosive (UN 2215, Class 8). It causes severe skin burns, eye damage, and allergic reactions. Always use ventilation and PPE. Store cool, dry, sealed, away from oxidants. Keep away from food and feed.

Sourcing Tips

• Choose grade: standard or high-purity.

• Select form: molten liquid, flakes, or pastilles.

• Request COA, SDS, and REACH registration.

• Buy from reliable suppliers for consistent quality and bulk pricing.

Conclusion
Maleic anhydride is essential for many industrial processes. Understanding its uses, safety, and sourcing helps you buy smarter and stay compliant.