Preparation Of ZIF-67 Hybrid And Its Effect On Flame Retardancy Of Epoxy Resin

Epoxy resin has been used in all walks of life because of its excellent performance.But epoxy resins are flammable and can produce toxic fumes,making people more likely to be exposed to fumes,thus limiting their use.Therefore,in this paper,a series of different flame retardants were synthesized and added to the epoxy resin to reduce the combustion risk of epoxy resin and the toxic smoke produced during the combustion of epoxy resin,so as to improve its application value and protect the safety of human body,mind and property.1.First,ZIF-67/g-C₃N₄(ZC)hybrid material was prepared by electrostatic adsorption of ZIF-67 on carbon nitride(g-C₃N₄).Then,ZIF-67/g-C₃N₄@Si O₂(ZCS)hybrid material was prepared by coating Si O₂ on ZC surface by sol-gel method.Infrared spectroscopy,X-ray diffractometer(XRD),and scanning electron microscopy(SEM)were used to investigate the structure and morphology of ZCS.It was proved that the ZCs were successfully prepared.And ZCS was added to the epoxy resin by physical stirring to test its properties.It has been found that the potential fire hazard of EP can be reduced by adding ZCS hybrids.EP composites with 3wt%ZCS content have better fire safety than EP.Cone calorimetry results revealed that the heat release and smoke emission of EP composites were reduced to varying degrees,particularly their peak heat release rate,total heat release rate,peak smoke production rate,and total smoke production were reduced by 46.8%,21.7%,45.2%,and19.3%,respectively.2.In the first step,urea and Fe-MMT are mixed and calcined in a certain proportion by the high-temperature calcination method to prepare g-C₃N₄/Fe-MMT(CM)compound.In the second step,g-C₃N₄/Fe-MMT@ZIF-67(CMZ)hybrid material was prepared by loading ZIF-67 on CM surface by electrostatic action.And the prepared CMZ hybrid material was added into the epoxy resin to explore its influence on the thermal stability,flame retardant and smoke suppression properties of the epoxy resin.The results of thermogravimetry analysis(TGA)showed that the thermal stability of the epoxy resin composites was significantly enhanced with the addition of CMZ,and the carbon residue rate was increased by nearly 47.8%.It was also found by cone test that the peak heat release rate and smoke release rate of the composites were significantly reduced when the amount of CMZ introduced into the epoxy resin was 6wt%.It was also found by digital photo,SEM,Raman and other test results that the addition of CMZ could make EP form a more dense carbon layer,thus improving the epoxy resin safety performance.3.CS@ZIF-67 hybrid material was synthesized by simple blending precipitation preparation method.First,FTIR,XRD and other characterization were used to prove the successful preparation of CS@ZIF-67.Secondly,CS@ZIF-67 was used to improve the flame retardant and smoke suppression properties of epoxy resin.The properties of the composites were tested and analyzed by vertical combustion test(UL-94),Limiting oxygen index test(LOI),cone calorimeter test(CC),scanning electron microscope and Raman test.The results of UL-94 and LOI showed that CS/ZIF-67 could improve the UL-94 grade and LOI value of EP.The results of cone calorimetry showed that the heat release rate and smoke release rate of CS@ZIF-67/EP composite were decreased compared with that of epoxy resin,and the carbon residue was increased.The SEM and Raman results showed that the addition of CS@ZIF-67 made EP can form a more dense carbon layer,which has a positive effect on the carbon formation of the polymer.Figure[39]table[19]reference[101]...