Purified terephthalic acid

Purified terephthalic acid, commonly abbreviated PTA, is an aromatic dicarboxylic-acid monomer used primarily in polyester manufacture. Its two para-positioned carboxyl groups react with glycols to build polymer chains. The aromatic ring supplies a rigid structural unit that contributes to the mechanical and thermal characteristics of polyethylene terephthalate and related polyesters.

The polyester-grade white powder is introduced as a reactive feedstock rather than a particulate filler in the finished polymer. Purification is important because residual intermediates and color-forming impurities can affect downstream polymer quality. PTA differs from isophthalic acid in substitution geometry and from dimethyl terephthalate in its ester functionality. The selected glycol and any comonomers establish the final polyester composition.

Typical Applications

• Bottle-grade PET resin: Used with ethylene glycol to manufacture PET for beverage and other packaging containers. The aromatic diacid forms the terephthalate portion of the polymer backbone.
• Polyester textile and industrial fibers: Used in polyester production for filament and staple fibers. Polymerization and subsequent spinning convert the monomer feedstock into fibers with the required processing and end-use properties.
• Polyester films and sheets: Used upstream in PET and related polyester resins for film and sheet manufacture. The resulting polymer is processed into packaging, electrical and other technical film products.

Specifications

Specifications describe the standard grade. Tolerance, test method and documentation package are confirmed per order.