Background and overview[1][2]
Tolyl diphenyl phosphate is a colorless and odorless transparent liquid with good compatibility, excellent oil resistance, and good insulation resistance. It has low volatility, good water stability, good flame retardancy and excellent plasticizing effect. It is a flame retardant plasticizer with low temperature resistance and good wear resistance. In addition to being widely used in PVC resin, vinyl chloride copolymer and nitrocellulose, it can also be used as a flame retardant treatment agent for fabrics. It not only has plasticity but also has good flame retardancy. It is a good flame retardant treatment agent. .
Physical and chemical properties and structure[1]
Creyl diphenyl phosphate (CDP), also known as tolyl diphenyl phosphate or phenylmethylphenyl phosphate, is a flame retardant. Its molecular formula is: C19H17O4P; CAS: 26444-49 ‑5, its relative molecular mass is 340.31; the theoretical phosphorus content is 9.10%. The physical and chemical properties of diphenyl toluene phosphate are: the industrial product is a colorless or light yellow transparent liquid; it has compatibility and low temperature characteristics; it has low volatility; relative density: (20℃) 1.191-1.212, freezing point <-30℃, Boiling point: 360℃ (760mmHg), flash point (open cup method) 220℃-230℃.
Diphenyl toluene phosphate
Apply[3]
Toluene diphenyl phosphate is an additive flame-retardant plasticizer with excellent compatibility, oil resistance, electrical insulation, good hydrolysis stability, low volatility, high plasticizing efficiency, good low-temperature characteristics and wear resistance of products. , the main plastic antibacterial agent should be suitable for PVC, VC copolymer, polyvinyl acetal, nitrocellulose, cellulose acetate, butyl cellulose acetate, natural and synthetic rubber and other flame retardants, plasticizers, gasoline and lubricants Oil additives.
Preparation[2]
Pump 430 kg of m-p-cresol and 710 kg of molten phenol into the reaction kettle at a time, and add a certain amount of calcium and magnesium catalyst; when the temperature of the material (you can stir for a while) is less than 50°C (stop stirring), add 570 kg Pump phosphorus oxychloride into it; start the normal pressure acid discharge system, start stirring, slowly feed steam into the jacket, and start heating. It takes about 1.5 hours, and the liquid temperature rises to about 70°C. Afterwards, check the reaction situation in the kettle. At a speed of about 4-5℃ per hour, raise the temperature to 95℃, balance for 1 hour, then rise to 125℃ at 4-5℃/hour, and then rise to about 140℃ at 5-7℃/hour, start negative pressure acid discharge The system takes about 1.5 hours to heat up to about 160℃, and the negative pressure is above 720mmHg for 2 hours to drain the acid. After the acid draining is completed, take a sample to measure the acid value, and add an appropriate amount of alkali (NaCO3 or NaOH) based on the result to neutralize it. The temperature is at 155± 5℃, negative pressure greater than 680mmHg, about 2 hours after exhaust, when the measured acid value is less than 4mgKOH/g, the esterification is completed to crude ester.
Pump the crude ester into the distillation pot, raise the temperature and separate by negative pressure distillation; collect low boilers, middle distillates, and finished products separately; when collecting finished products, pay attention to flow, color, acid value, liquid temperature, and vacuum degree After distillation, the finished product is filtered into a storage tank, sampled and analyzed to be qualified, filtered, packaged and stored in the warehouse.
The mass ratio of m-p-cresol:phenol:phosphorus oxychloride:calcium magnesium catalyst is 430:710:570:5;
Operational handling and storage
Closed operation. Closed operation to provide good natural ventilation conditions. Operators must undergo special training and strictly abide by operating procedures. It is recommended that operators wear self-priming filter gas masks (half masks), chemical safety glasses, anti-toxic substance penetration overalls, and chemical-proof gloves. Keep away from fire and heat sources. Smoking is strictly prohibited in the workplace. Use explosion-proof ventilation systems and equipment. Prevent vapors from leaking into the workplace air. Avoid contact with oxidants, acids, and alkalis. When handling, load and unload with care to prevent damage to packaging and containers. Equipped with corresponding varieties and quantities of fire-fighting equipment and leakage emergency treatment equipment.
Storage Notes:
Stored in a cool, ventilated warehouse. Keep away from fire and heat sources. They should be stored separately from oxidants, acids, and alkalis, and avoid mixed storage. Equipped with fire-fighting equipment of corresponding varieties and quantities of Dow Corning emulsion. The storage area should be equipped with emergency release equipment and suitable containment materials.
Main reference materials
[1] Wu Gang, Tang Fubin, Zhao Shanhong, Wang Lijun, Guo Fanglong, & Li Dan. (2014). Determination of phosphate plasticizers in textiles by accelerated solvent extraction-gas chromatography. Silk, 51(3), 29-33 .
[2] Kang���, Han Jian, Ding Xinbo, Xu Guoping, Yu Bin, & Xu Changya. (2013). Research on the influence of flame retardant plasticizers on the flame retardant properties of PVC materials. Journal of Zhejiang Sci-Tech University (Natural Science Edition), 30(5), 663-666.
[3] Ma Yongming, Wei Wenjing, Zhang Yungang, Liu Xiaochen, & Cai Yongyuan. (2013). Application progress of phosphate ester fabric flame retardants. Thermosetting Resins (4), 59-63.
