Study On The Synthesis Of Bis(4-carboxylphenyl) Phenyl Phosphine Oxide

The main work of the article was to synthesize a suitable monomer, bis(4-carboxyphenyl)phenyl phosphine oxide (BCPPO), as the retardant for poly(ethylene terephthalate) (PET) fibre. The procedures were divided into three steps: dichloride phenyl phosphine oxide (DCPP) was synthesized and bis(4-methyl phenyl)phosphate oxide(BMPPO) was prepared from DCPP by Friedel-Crafts reaction. BCPPO was produced by two steps of oxidizing BMPPO with KMnO4 and O2.The procedures were improved and optimized by reviewing different factors effects. The product was identified by elements analysis, DSC analysis, MS analysis, GAS chromatogram, infrared chromatogram, acid number and so on. The physical constants of products were measured, which provided evidences for experiment and industrialization plan.Some improvements were made in this synthesis method. First, sodium chloride was adopted as the separation reagent in the process of DCPP synthesis, which had approving effect and the reaction is easy to control. The environment pollution was decreased and production cost was reduced. Second, the H2O2 and 67 were substituted for KMnO4 as oxidant in the oxidation process. Third, acetic acid was adopted as solvent, which made environment pollution reduced and production cost decreased, too.