For chemical professionals, understanding the fundamental properties and synthesis pathways of key compounds is essential for innovation and effective application. Cis-1,2,3,6-Tetrahydrophthalic Anhydride (THPA), known by its CAS number 935-79-5, is a compound of significant industrial interest, prized for its reactivity and utility across various chemical sectors. As a white flake solid, THPA’s chemical characteristics make it a valuable intermediate and curing agent.

The molecular formula of THPA is C8H8O3, with a molecular weight of 152.15 g/mol. Its structure is derived from the Diels-Alder reaction between butadiene and maleic anhydride. This reaction, a cornerstone of organic synthesis, allows for the efficient formation of cyclic compounds with specific stereochemistry. In the case of THPA, the reaction yields the cis isomer, which is the commercially relevant form. The presence of the anhydride functional group makes THPA highly reactive towards nucleophiles, such as alcohols and amines, which is key to its function as a curing agent and its utility in subsequent synthetic steps.

Key physical properties of THPA include a melting point of approximately 98°C and a boiling point around 234.6°C. It exhibits limited solubility in water, reacting with it to form the corresponding dicarboxylic acid, cis-1,2,3,6-Tetrahydrophthalic acid. However, it is soluble in organic solvents like benzene and toluene. Its stability is generally good under dry conditions, but its sensitivity to moisture necessitates careful storage in sealed containers in a cool, dry environment.

The synthesis of THPA primarily involves the Diels-Alder cycloaddition reaction. In a typical laboratory or industrial preparation, maleic anhydride is reacted with 1,3-butadiene, often in a suitable solvent. The reaction is exothermic and requires controlled conditions to optimize yield and purity. After the reaction, the product is usually isolated through crystallization or other separation techniques to achieve the desired high purity, commonly 99% or more.

From a functional perspective, THPA's role as an epoxy resin curing agent is critical. When mixed with epoxy resins, the anhydride ring opens and reacts with the epoxy groups, forming ester linkages and cross-linking the polymer chains into a rigid, thermoset network. This process results in materials with enhanced mechanical properties, excellent thermal stability, and superior chemical resistance, making them suitable for demanding applications in coatings, adhesives, and composites.

For researchers and developers, understanding these chemical properties is crucial for optimizing formulations and synthesis strategies. When you are looking to buy THPA, sourcing from a reputable chemical manufacturer or supplier ensures you receive a product with consistent quality and well-defined specifications. The price of THPA is influenced by the purity and scale of production, but its value in enabling high-performance materials is undeniable.

As a specialist in fine chemicals, we are committed to providing high-quality THPA. Whether you are engaged in epoxy resin formulation, polymer modification, or complex organic synthesis, our product can meet your needs. We encourage you to contact us to learn more about the chemical and physical properties of our THPA and to discuss how we can fulfill your procurement requirements for this essential chemical intermediate.