Brief Overview
Dioctyl terephthalate (DOTP) is a non-phthalate plasticizer that is commonly used in the production of various plastic and polymer products. It is a clear, colorless liquid that is highly resistant to heat and has a high degree of compatibility with PVC, making it an ideal replacement for traditional phthalate plasticizers. Unlike some phthalate plasticizers, DOTP is not considered a reproductive or developmental toxin and has a low potential for acute toxicity. As a result, it has been approved for use in a variety of food contact applications and medical devices.
Manufacturing Process
Esterification: The first step in the process involves the esterification of terephthalic acid with 2-ethylhexanol. This reaction is typically carried out in the presence of a catalyst, such as titanium or antimony, and produces bis(2-ethylhexyl) terephthalate (DEHT).
Transesterification: The DEHT is then subjected to transesterification with 2-ethylhexanol to produce DOTP. This reaction is typically carried out in the presence of a catalyst, such as zinc or calcium, and involves the exchange of one of the ethylhexyl groups in DEHT with an ethylhexyl group from 2-ethylhexanol.
Purification: The DOTP is then purified to remove any remaining impurities, such as catalyst residues and unreacted starting materials. This is typically done through a combination of processes, including distillation, filtration, and washing.
