Description

4-Sulphophthalic Anhydride is a key sulfonated aromatic anhydride derivative, serving as a versatile intermediate in the synthesis of specialty chemicals. Its value lies in introducing both sulfonic acid and anhydride functionalities, enabling the creation of water-soluble polymers, dyes, and advanced materials. This compound is essential for manufacturers in the polymer, dye, and pharmaceutical intermediate industries seeking to enhance solubility or introduce reactive sites into their products.

Application

• Polymer Modification: As a monomer or co-monomer for synthesizing sulfonated polyimides, polyamides, and polyesters, imparting enhanced hydrophilicity, proton conductivity, or dyeability.
• Dye and Pigment Synthesis: A crucial intermediate for producing water-soluble acid dyes, reactive dyes, and fluorescent brightening agents.
• Pharmaceutical Intermediates: Used in the synthesis of certain sulfonated drug candidates and diagnostic agents.
• Crosslinking Agent: Functions as a crosslinker in resin systems and coatings to improve thermal and chemical resistance.
• Surfactant and Detergent Intermediate: Employed in the production of specialized anionic surfactants with unique solubility profiles.
• Analytical Reagent: Used in the preparation of reagents for analytical chemistry and biochemistry.
• Ion-Exchange Resins: Serves as a precursor for manufacturing cation-exchange resins with specific selectivity.
• Adhesive and Sealant Formulations: Incorporated to modify the properties of adhesives, enhancing performance in specific environments.

Basic Information

Item	Detail
Product Name	4-Sulphophthalic Anhydride
CAS No.	134-08-7
Molecular Formula	C8H4O6S
Molecular Weight	228.18 g/mol
Synonyms	4-Sulfophthalic Anhydride; 4-Sulfobenzoic Anhydride; 1,3-Dioxo-1,3-dihydroisobenzofuran-5-sulfonic Acid; 5-Sulfoisobenzofuran-1,3-dione; Benzoic acid, 4-sulfo-, cyclic anhydride; 4-Carboxybenzenesulfonic Acid Anhydride; Phthalic Anhydride-4-sulfonic Acid; SPAn
EINECS	205-130-5

Quality Control

Our 4-Sulphophthalic Anhydride is produced under a stringent quality management system to ensure batch-to-batch consistency and reliability. Each lot undergoes comprehensive analytical testing, including assay, impurity profiling, and confirmation of key physical properties. A Certificate of Analysis (COA) detailing all test results is provided with every shipment, ensuring full traceability and compliance with your internal quality standards and relevant industry guidelines.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry, and well-ventilated area at a controlled room temperature (15-25°C). Due to its hygroscopic (moisture-sensitive) nature, the container must be kept sealed immediately after use to prevent degradation by atmospheric moisture. Keep away from incompatible materials such as strong bases and amines.

Specification

Item	Specification
Appearance	White to off-white crystalline powder
Identification (IR)	Conforms to structure
Assay (HPLC)	≥ 98.0%
Water Content (KF)	≤ 1.0%
Sulfate Ash	≤ 0.2%
Heavy Metals (as Pb)	≤ 20 ppm
Melting Point	Contact for details

Note: Specifications can be tailored. Please contact us for the detailed technical data sheet of a specific grade.