Study On Chemical Analysis And Preparation Of Flame Retardant Epoxy Resin Casting Materials

Epoxy resin casting system has excellent mechanical properties,heat resistance,stability and uniqueness,and has a wide range of applications in aerospace,aviation,electrical packaging,construction,insulation materials and other fields.Under certain specific engineering application conditions,such as high-voltage insulation packages and dry-type transformers,there are specific industry standards for flame retardant performance.In order to follow up the advanced flame retardant epoxy resin castables in the market,in this paper,through chemical separation,chromatographic analysis and spectral analysis,a preliminary composition analysis of a company's flame-retardant epoxy resin castable was made.On this basis,the corresponding insulating castable was simulated,and its mechanics and resistance were tested Ignitability.The main research contents of this paper are as follows:First,the sample was preliminarily separated by conventional chemical methods,and the inorganic filler and organic resin were disassembled and separated,Comprehensive analysis by infrared spectroscopy(FTIR),gas chromatography mass spectrometry(GC-MS),liquid chromatography(HPLC),nuclear magnetic resonance(NMR),X-ray diffraction(XRD),scanning electron microscope(SEM),and energy spectroscopy(EDS),confirmed that the organic resin in the sample is roughly EP828,and neopentyl glycol diglycidyl ether(678).In addition,various chromatograms and spectra show that the curing agents are Methyltetrahydrophthalic anhydride and neopentyl glycol.The sample also contains a mixture of carbon black,silica,decabromodiphenylethane(DBDPE),and antimony trioxide(Sb₂O₃),Secondly,on the basis of chromatographic and spectroscopic analysis,epoxy resin castables were designed and formulated,and the viscosity,mechanical properties,glass transition temperature of the casting system were investigated using rotary viscometer,DSC,universal tensile machine and other test methods(T_g)and gel time,and optimize the casting glue formula.Through performance comparison,the optimized basic formula is:EP828 resin 100pbw(parts by weight),MTHPA anhydride curing agent 97pbw,PEG400-PPG400 18pbw as a toughening agent,benzyl dimethylamine(BDMA)0.3pbw and tetrabutyl Ammonium bromide(TBAB)0.9pbw as a promoter and 400 mesh silica filler 215pbw,the entire epoxy resin casting system at 150?gelation time reached2.49min,flexural strength of 100MPa,flexural modulus of 0.978 GPa,glass transition temperature is 92.3?.Finally,try the reactive organic flame retardant(phosphorus/bromine),additive organic/inorganic flame retardant(DBDPE/Sb₂O₃)and additive inorganic material(Si O₂)in the basic ingredients of the optimized formula.When the weight fraction of brominated epoxy/triphenyl phosphate added is 40/5 pbw,the limiting oxygen index value is 28.2,and UL-94 vertical combustion reaches the V-1 level.When the weight part of DBDPE/Sb₂O₃ added is 25/8.33 pbw,the LOI value is 27.5,and UL-94 vertical combustion reaches the V-1 level.