Industrial, UPR Grade & High Purity Maleic Anhydride (MA) CAS 108-31-6 Basic Organic Raw Material for Unsaturated Polyester Resin, Coatings & Fine Che

Maleic Anhydride (Abbr: MA, also known as cis-Butenedioic Anhydride, CAS: 108-31-6, EINECS: 203-571-6, HS Code: 2917140000) is a white flaky or needle-like crystalline solid with a characteristic pungent odor, with the molecular formula C₄H₂O₃ and molecular weight 98.06. We supply industrial grade and premium grade products complying with international quality standards. It is readily soluble in acetone, chloroform and most organic solvents, reacts with water to hydrolyze into maleic acid, and features high chemical reactivity, enabling esterification, polymerization and Diels-Alder addition reactions. As one of the most important basic organic chemical raw materials, it is widely used in unsaturated polyester resin, coatings, pesticides, pharmaceuticals, plasticizers and fine chemical industries.

Applications
Unsaturated Polyester Resin Industry (Core Application)
The core raw material for unsaturated polyester resin (UPR) production, accounting for the largest downstream consumption proportion. It reacts with glycols and dibasic acids to synthesize UPR, which is further processed into glass fiber reinforced plastics, artificial marble, sanitary ware, composite materials and anticorrosive coatings, being an essential base material for construction, shipbuilding and automotive industries.
Coating & Alkyd Resin Industry
Used for producing alkyd resins, amino coatings and epoxy resin curing agents. It improves coating adhesion, gloss, hardness and weather resistance, and is widely applied in industrial anticorrosive paints, architectural coatings and wood coatings to optimize film-forming performance and reduce formulation costs.
Pesticide & Pharmaceutical Intermediate
Key intermediate for synthesizing organophosphorus pesticides such as malathion and pyridaphenthion, as well as pyrethroid insecticides and fungicides. In the pharmaceutical field, it is used to produce chlorpheniramine maleate, antimalarial drugs and other active pharmaceutical ingredients, supporting the production of various antiallergic and therapeutic drugs.
Fine Chemical & Plasticizer Sector
Raw material for manufacturing maleate plasticizers, water treatment agents and lubricant additives. It is also the base material for producing 1,4-butanediol, γ-butyrolactone, tetrahydrofuran, succinic acid and other high-value fine chemical products, covering the entire industrial chain of downstream deep processing.
Papermaking & Printing Ink Industry
Applied as paper sizing agent and ink resin modifier. It enhances paper surface strength and water repellency, improves ink adhesion and drying speed on printing substrates, and effectively elevates the production efficiency and product quality of papermaking and printing processes.
Other Industrial Scenarios
Widely used as dienophile in Diels-Alder organic synthesis, as crosslinking modifier for various polymer materials, and as raw material for food-grade acidity regulators after purification, meeting the diversified demands of different industrial segments.

Product Advantages
✅ High purity & low impurities: ≥99.5% main content with ultra-low moisture and residue, stable reaction performance and fewer by-products in downstream processing
✅ High reaction activity: Typical unsaturated acid anhydride structure, efficient in esterification, addition and polymerization reactions, effectively improves production yield
✅ Stable batch quality: Strict process control ensures consistent melting point and chroma between batches, suitable for large-scale continuous industrial production
✅ Multiple product forms: Available in flake, briquette and molten bulk forms, matching different transportation and production process requirements
✅ Mature industrial chain: Sufficient production capacity with stable supply, competitive market price and reliable long-term delivery guarantee
✅ Wide application coverage: As a basic chemical raw material, it covers dozens of downstream industries, with strong versatility and high industrial value

Packaging & Storage
Standard packaging: 25kg paper-plastic composite bags with inner PE liner; 500kg / 1000kg FIBC bulk bags for large orders; molten bulk delivery via tank truck is also available. The product is hygroscopic and easy to hydrolyze when exposed to moisture. Store in a cool, dry and well-ventilated warehouse at below 35°C. Keep containers tightly sealed, strictly protected from moisture and rain, and stored separately from alkalis, oxidants and food raw materials. Shelf life is 12 months under proper storage conditions.
Safety Information
Classified as Class 8 corrosive substance for transportation (UN 2215, Packing Group III). Its dust and vapor are irritating to eyes, skin and respiratory tract, may cause burns and allergic skin reactions, and inhalation may induce asthma symptoms. Wear protective goggles, acid-resistant gloves and dust mask during handling, and operate in a well-ventilated environment. In case of skin or eye contact, rinse immediately with plenty of clean water for at least 15 minutes and seek medical attention. Complete MSDS and relevant qualification certificates are available upon request.

With 15 years of experience in chemical foreign trade, we offer the following core strengths to support your procurement needs:
1.A 70,000 ㎡ warehouse (20,000 MT capacity) with moisture-proof and temperature-controlled systems, enabling efficient fulfillment of large-volume orders.
2.Free samples (Ship within 3-7 days) to let you test products at zero trial cost.
3.Transparent lead time for hazardous chemicals: 45–60 days, with clear delivery schedules.
4.Certified with a Hazardous Chemical Business License and ISO certification, ensuring smooth customs clearance.
5.6 packaging options with customizable logos to minimize product loss during transportation.
6.Over 400 chemical SKUs available for one-stop procurement, helping you reduce sourcing costs.
Please share your purchase volume, target market, and other requirements, and we will tailor a customized solution for you!