Application | flame retardant is a substitute for halogen-type flame retardant, used in the production of halogen-free flame retardant epoxy resin, can be used for the packaging of semiconductor materials, flame retardants for printed circuit boards, led luminous tubes, etc., for products that must comply with rohs requirements, intermediates for the synthesis of reactive flame retardants, etc. |
preparation | in the master's thesis "synthesis of DOPO derivatives" of Nanjing University of Science and Technology, it is mentioned that DOPO and p-benzoquinone are used as the reaction raw materials, tetrahydrofuran is used as the reaction solvent, tetrahydrofuran recrystallization is used as the process route, toluene is used as the reaction solvent, and ethanol recrystallization is used as the process route, by comparing the above two processes, toluene was selected as the reaction solvent, and the process parameters were discussed. Synthesis and characterization of novel phosphorus-containing flame retardants (ODOPB) and fine chemical intermediates (Volume 41, Issue 5, 2011) research on the synthesis process of the new phosphorus-containing flame retardant DOPO-HQ, on the basis of the paper "synthesis of DOPO derivatives", the production of DOPO-HQ was further studied, the main research contents of the two papers are as follows: the reaction raw materials DOPO and p-benzoquinone are kept unchanged, and toluene, tetrahydrofuran and ethylene glycol monoethyl ether are used as solvents for comparison, the resulting precipitate was cooled to room temperature, filtered, washed several times with a solvent, then dried to give a crude product, recrystallized from ethanol, and dried under vacuum to give the final product. The above processes have the following problems: the process stability is poor, the product quality is good or bad, mainly in the appearance of the product (when the color is light and heavy), the purity of the crude product is between 50 and 90%, it brings great trouble to the post-treatment process; The product yield is low; The reaction process is carried out under the condition of solvent reflux, the solvent loss is large, and can not be reused; Toluene, ethylene glycol monoethyl ether and tetrahydrofuran have strong toxicity, bad smell, flammable and explosive, The environment of the process operation unit is bad and the risk is high. During The recrystallization operation, the product cannot be completely dissolved in ethanol, tetrahydrofuran and other solvents, and the purity of the product cannot be effectively improved, and the product quality is difficult to meet the standard. |