Preparation Of Three-dimensional Structure Complex And Its Effect On Flame Retardancy And Thermal Conductivity Of Silicone Rubber

Silicone rubber has the characteristics of high and low temperature resistance,aging resistance and electrical insulation,but it also has the defects of flammability and low thermal conductivity.In this work,different three-dimensional nanohybrids were synthesized and added to methyl vinyl silicone rubber（MVQ）to prepare MVQ composites;the effects of different hybrids on the flame retardancy and thermal conductivity of MVQ were studied.The specific research contents are as follows:1.Three-dimensional modified boron nitride-iron oxyhydroxide hybrids（BN-β-Fe OOH）were prepared by hydrothermal method and MVQ composites were prepared,and the effect of BN-β-Fe OOH on the properties of MVQ composites was studied.The results show that the addition of BN-β-Fe OOH can increase the limiting oxygen index（LOI）of MVQ,reduce the heat release of MVQ during combustion and improve the thermal conductivity of MVQ.When 3 phr by mass of BN-β-Fe OOH were added,the LOI of the MVQ composites increased to 29.8%,and the peak heat release rate（p HRR）and total heat release（THR）decreased by 29.8%and 34.5%,respectively.The possible flame retardant mechanism is proposed by analyzing the combustion products.2.Three-dimensional structure modified carbon nanotube hybrid（KH550@CNTs-β-Fe OOH）was prepared by in-situ growth and organic grafting,and MVQ composite was prepared.The effect of KH550@CNTs-β-Fe OOH on the properties of MVQ composites was studied.The results show that the KH550@CNTs-β-Fe OOH join,make MVQ composite maximum decomposition temperature and 700℃when the residue increased significantly.When only 1 phr by mass of KH550@CNTs-β-Fe OOH was added,the LOI of the MVQ composite was increased to 31.0%,and the thermal conductivity was also increased by 15.2%.3.The three-dimensional structure Fe₂O₃@C-N-CNTs was obtained by high temperature carbonization and surface grafting,and the MVQ composite was prepared.The results showed that when the mass fraction of Fe₂O₃@C-N-CNTs was 3 phr,the p HRR and THR of MVQ composite decreased by 37.0%and 29.6%,respectively.At the same time,the addition of Fe₂O₃@C-N-CNTs can effectively reduce the volume resistivity of MVQ.When the mass fraction of Fe₂O₃@C-N-CNTs is 3 phr,the volume resistivity of MVQ decreases to 4.6×10~8Ω·cm,which is of great significance for improving the antistatic ability of MVQ composites.Figures[58]Tables[23]References[88]...