P-Phthalic acid CAS 100-21-0

P-Phthalic acid, also known as terephthalic acid, is an aromatic dicarboxylic acid with the chemical formula C₈H₆O₄ and a CAS number of 100-21-0. It is characterized by the presence of two carboxylic acid groups attached to a benzene ring at the para positions (1,4). This compound appears as a white crystalline solid and is primarily utilized in the production of polyester fibers and resins, which are essential in various industries including textiles, packaging, and automotive applications.
Chemical Properties and Uses
Chemical Structure: Terephthalic acid is a benzenedicarboxylic acid, specifically with carboxyl groups at the 1 and 4 positions on the benzene ring. This structural arrangement contributes to its properties and applications in polymer chemistry.
Applications: The primary use of terephthalic acid is as a precursor in the synthesis of polyethylene terephthalate (PET), a widely used polymer in the production of plastic bottles, containers, and synthetic fibers. Additionally, it serves as a key ingredient in the manufacture of various coatings, films, and engineering plastics due to its excellent thermal stability and chemical resistance.
Production: Terephthalic acid is typically produced through the oxidation of p-xylene or naphthalene, followed by hydrolysis to yield the acid. The purity of the final product is crucial for its effectiveness in industrial applications, necessitating stringent quality control measures during production.
Safety and Handling
Terephthalic acid is generally considered safe for use in industrial applications; however, it can cause irritation to the skin, eyes, and respiratory tract upon exposure. Proper handling and safety measures should be observed to minimize any potential health risks associated with its use.
In summary, p-phthalic acid (terephthalic acid) is a vital chemical compound in the production of various materials, particularly in the plastics and textiles industries, owing to its favorable chemical properties and versatility.