DBDPE-Sb2O3协同阻燃沥青的性能与机理

为分析DBDPE-Sb2O3协同阻燃沥青的性能及其阻燃机理,采用动态剪切流变仪试验、弯曲梁流变试验、限氧指数试验、锥型量热仪试验和热重-热差试验的方法,研究了DBDPE-Sb2O3阻燃剂对SBS改性沥青路用性能、阻燃性能与热稳定性的影响。结果表明:DBDPE-Sb2O3阻燃剂提高了SBS改性沥青的稠度和高温抗变形能力,降低了SBS改性沥青的塑性和低温抗开裂性能;DBDPE或Sb2O3单独使用对SBS改性沥青极限氧指数和最大烟密度延缓时间提高的不明显,但DBDPE-Sb2O3复配使用显著提高了SBS改性沥青的极限氧指数和最大烟密度延缓时间,显著降低了SBS改性沥青路面的热释放速率、总释放热量和总烟产量;沥青分解全过程,DBDPE与Sb2O3反应生成的高密度气态SbBr3隔离了燃烧区氧气,有效抑制了SBS改性沥青的热解与氧化;DBDPE-Sb2O3阻燃剂提高了SBS改性沥青的高温性能和阻燃抑烟性能,降低了SBS改性沥青的低温性能,其掺量为4%~8%时,可使SBS改性沥青具有较好的路用性能和阻燃抑烟性能;DBDPE与Sb2O3协同对SBS改性沥青起气相阻燃作用,复配使用显著提高了SBS改性沥青的阻燃性能,且对SBS改性沥青路面起到了良好的阻燃效果。

Performance and Flame Retardant Mechanism of Coordinated Flame Retardant Asphalt with DBDPE and Sb2O3

To analyze the performance and flame retardant mechanism of DBDPE-Sb₂O₃ flame retardant asphalt, its effects on road performance, flame retardancy, and thermal stability of SBS modified asphalt were studied using a dynamic shear rheometer test, bending beam rheological test, limiting oxygen index test, cone calorimeter test, thermo gravimetric test, and differential thermal test. Even though the DBDPE-Sb₂O₃ flame retardant improves the consistency and high temperature anti-deforming capability of SBS modified asphalt, it reduces the plasticity and low temperature cracking resistance. DBDPE or Sb₂O₃ flame retardant has little effect on the increase of the limit oxygen index and delay time of maximum smoke density of SBS modified asphalt. However, the composite flame retardant of DBDPE and Sb₂O₃ can significantly improve the limit oxygen index and delay time of maximum smoke density. Moreover, it can considerably reduce the heat release rate, total heat release, and amount of smoke release of the SBS modified asphalt pavement. Throughout the asphalt decomposition process, the high density gas SbBr₃ is formed by the reaction of DBDPE and Sb₂O₃, thereby separating the oxygen in the combustion zone and effectively inhibiting the pyrolysis and oxidation of SBS modified asphalt. Research shows that the DBDPE-Sb₂O₃ flame retardant improves the high temperature performance, flame retardancy, and smoke suppression performance of SBS modified asphalt but reduces the low temperature performance. When the content of the DBDPE-Sb₂O₃ flame retardant is 4%-8%, SBS modified asphalt yields good road performance, flame retardancy, and smoke suppression performance. The combination of DBDPE and Sb₂O₃ exhibits synergistic flame retardant behavior and can significantly improve the flame retardant performance of SBS modified asphalt and have an effective vapor flame retardant effect on SBS modified asphalt pavement.