[Chemical Knowledge]：The nature, use, upstream and downstream raw materials, storage methods of dioctyl phthalate, is dioctyl phthalate toxic

Properties of Dioctyl Phthalate

Dioctyl phthalate (Dioctyl Phthalate, or DOP) is a colorless, odorless liquid chemical. Its chemical formula is C24H38O4 and its molecular weight is 390.56g/mol. DOP has a high volatility, with a boiling point of 386°C, a flash point of 216°C, and a density of about 0.985g/cm³(20°C). Due to its chemical structure, DOP has excellent flexibility and plasticity, making it an extremely important plasticizer, especially in the plastics industry.

Use of dioctyl phthalate

The most important use of DOP is as a plasticizer, which can improve the flexibility, durability and plasticity of materials. Widely used in polyvinyl chloride (PVC) products, such as PVC flooring, wallpaper, artificial leather, wire and cable sheath, etc. DOP is also used in rubber, cellulose, resin and other products to improve its processing performance and the flexibility of the final product. DOP is also used as a solvent in coatings, adhesives and paints to reduce viscosity and improve coating performance.

Dioctyl phthalate upstream raw material

The production of DOP involves a variety of upstream feedstocks, the most critical of which are phthalic anhydride (Phthalic Anhydride) and 2-ethylhexanol (2-Ethylhexanol). Phthalic anhydride is mainly produced from o-xylene (o-Xylene) by oxidation, while 2-ethylhexanol is synthesized from acetaldehyde and hydrogen. In order to obtain high-purity DOP, these raw materials must have high purity, and the reaction conditions need to be strictly controlled during the reaction process to ensure product quality and production efficiency.

Dioctyl Phthalate Downstream Products

As an important plasticizer, DOP's downstream products cover many plastic products in daily life. Specifically, PVC products are the largest application area of DOP, and almost all PVC products that require flexibility will use DOP plasticization. For example, sheaths for cables and wires, hoses, leather products, plastic films, and artificial leather. DOP is also used in the manufacture of toys, medical equipment, automotive interiors and building materials, etc., to provide good performance and long service life.

Production Process of Dioctyl Phthalate

The production process of DOP mainly includes esterification reaction and purification process. In the esterification reaction, phthalic anhydride is reacted with 2-ethylhexanol in the presence of an acid catalyst such as sulfuric acid or p-toluenesulfonic acid to form DOP. This reaction is usually carried out at about 180 ° C., and strict control of temperature and reaction time is required to avoid the formation of by-products. After the reaction is completed, the product needs to undergo purification steps such as distillation and dehydration to remove unreacted raw materials and by-products to obtain high-purity DOP.

Dioctyl Phthalate Storage Method

DOP should be stored in a cool, dry, well-ventilated warehouse, away from direct sunlight and high temperature environment. Storage containers shall be made of opaque and well-sealed materials to prevent volatilization and oxidative deterioration of DOP. The warehouse shall be equipped with proper ventilation equipment to prevent the accumulation of DOP volatile gas. Because DOP is corrosive to a certain extent, contact with acid and alkali substances should be avoided during storage and transportation to avoid chemical reactions that may cause container damage or product quality degradation.

Dioctyl Phthalate Safety and Environmental Problems

Although DOP is widely used in industry, its safety and environmental protection issues cannot be ignored. DOP is considered to be a potentially hazardous substance that may have an impact on human health and the environment. Prolonged exposure to DOP may cause skin and eye irritation, and even damage to the liver, kidneys and other organs. The volatilization and leakage of DOP may cause pollution to the environment, especially difficult to degrade in water, and may have toxic effects on aquatic organisms after accumulation. Therefore, in the process of production and use of DOP, it is necessary to strictly abide by relevant safety and environmental regulations, and take effective protective measures to reduce its harm to the human body and the environment.

Dioctyl Phthalate Market and Prospect

As the demand for plastic products continues to grow, the market demand for DOP continues to rise. The vigorous development of the global plastics industry, especially the increasing demand for PVC products in emerging market countries, has promoted the growth of DOP consumption. Due to the health and environmental issues of DOP, many countries are looking for safer and environmentally friendly alternatives to plasticizers, such as dioctyl phthalate without o-benzene plasticizers (e. g., DINCH, DOTP, etc.). Therefore, the DOP market may face certain challenges in the future, but it also provides opportunities for the research and development of alternatives and market development.

Conclusion

As an important plasticizer, dioctyl phthalate is widely used in the plastics industry, and its properties and excellent plasticizing properties make it an indispensable chemical raw material. Despite the challenges of safety and environmental issues, the DOP industry still has broad market prospects through technological improvements and the development of alternatives. In the process of production and use, strict safety and environmental protection measures are essential to ensure its sustainable application in industry.