The invention belongs to the technical field of applied engineering plastics, and in particular, relates to a preparation method of a low-triphenyl phosphate engineering plastic halogen-free flame retardant. The method comprises the steps: under the action of a Lewis catalyst, carrying out a reaction of phenol with phosphorus oxychloride, reducing the pressure and distilling out excess phosphorusoxychloride, to obtain a mixture intermediate; carrying out a condensation reaction of the mixture intermediate and p-dihydroxybenzene, carrying out a reaction of the mixed intermediate with a properamount of p-dihydroxybenzene firstly, after a part of p-dihydroxybenzene is completely reacted, carrying out high vacuum dehydrochlorination, then adding triethylamine and the remaining p-dihydroxybenzene at relatively low temperature, and carrying out a reaction, wherein increase of the content of triphenyl phosphate is greatly reduced, toxicity to human bodies is reduced, and at the same time, the purity and the yield of the product are improved; and the preparation method has the advantages of simple process operation, short production cycle, economy and environmental protection, can satisfy the requirements of industrial scale production, and is suitable for industrialized popularization and application.

Preparation method of low-triphenyl phosphate engineering plastic halogen-free flame retardant

The present invention relates to a preparing method of a high yield bisphenol polycondensation phosphate, through the bisphenol compounds and phosphorus oxychloride reaction to obtain bisphenol polycondylated phosphorus acetyl chloride, then thionyl chloride can be added as a hydroxyl scavenger, the hydroxyl-containing phosphorus oxychloride presented by water can be re-converted to phosphorus oxychloride, thus sharply reducing the content of hydroxyl phosphate in the crude product of polycondensated phosphate ester reaction, and then through the distillation to remove excess phosphorus oxychloride, reacts with the unit phenolic compounds, the bisphenol polycondensated phosphate ester with low hydroxyl phosphate can be obtained, which will improve the yield of the product, and the product colors of polycondensation of polycondensated phosphate ester will not be affected due to the appliance of thionyl chloride as the hydroxyl group scavenger.

Preparing method of bisphenol polycondensated phosphate ester with high product yield

The invention relates to an industrialized preparation method for resorcinol phenyl-group polycondensation phosphate (RDP) low in triphenyl phosphate (TPP) content. The preparation method includes the steps that first, part of resorcinol and excessive phosphorus oxychloride react under catalyst presence to generate resorcinol phosphorus oxychloride polycondensate containing the excessive phosphorus oxychloride; under the vacuum action, most excessive phosphorus oxychloride is removed through distillation; then under the vacuum action, remaining bisphenol A is continuously added into obtained resorcinol phosphorus oxychloride polycondensate containing little phosphorus oxychloride; finally, the obtained resorcinol phosphorus oxychloride polycondensate containing a trace of phosphorus oxychloride and phenol react to prepare a resorcinol phenyl-group polycondensation phosphate (RDP) crude product, the RDP crude product is dissolved in methylbenzene and other dissolvent, and after acid pickling, alkaline washing and rinsing, the dissolvent and water are removed through reduced pressure distillation to obtain the RDP product. The preparation technology is simple, and the RDP low in TPP content is obtained on the premise of not additionally arranging production equipment and changing original production equipment.

Wang Qiuwei

Papers

Industrialized preparation method for resorcinol phenyl-group polycondensation phosphate (RDP) low in triphenyl phosphate (TPP) content