硅橡胶材料兼具有机材料柔韧性和无机材料的热稳定性,已经在各个领域取得了显著的增长。通过低温法制备了具有优异阻燃性能、较好力学性能、低成本、泡孔结构丰富的可膨胀石墨(EG)/硅橡胶泡沫复合材料,其可有效提高硅橡胶泡沫的阻燃性能。结果表明:添加10% EG可以提高硅橡胶泡沫的拉伸强度、断裂伸长率和硬度等力学性能指标,同时硅橡胶泡沫的密度增加,回弹性有所降低。锥型量热仪(CCT)测试表明,EG的添加有助于延迟点火时间(TTI),降低热释放速率(HRR)和总热释放量(THR)等参数,且有助于提高抑烟性能。适量添加EG可以改善硅橡胶泡沫的热稳定性,过量会导致产生“飞灰”现象。这些特征结合在一起预示着EG/硅橡胶泡沫复合材料由于出色的阻燃性质可在阻燃材料领域得到广泛的应用。
Silicone rubber material combines the flexibility of organic materials with the thermal stability of inorganic materials and has achieved significant growth in various fields.Here,we employed a low-temperature method to prepare expandable graphite (EG)/silicone rubber foam composite materials with excellent flame retardancy,good mechanical properties,low cost,and rich cellular structure,which could effectively improve the flame retardancy of silicone rubber foam.The results revealed that adding 10wt% EG could improve the mechanical properties of silicone rubber foam,including tensile strength,elongation at break,and hardness,while the density of the silicone rubber foam increased and the rebound resilience decreased.Cone calorimeter (CCT) testing showed that the addition of EG helped to delay time to ignition (TTI),reduce the heat release rate (HRR) and total heat release (THR),and improve the smoke suppression performance.Adding EG properly could enhance the thermal stability of silicone rubber foam,but excessive addition could lead to the phenomenon of “fly ash”.These characteristics collectively indicated that the expandable graphite (EG)/silicone rubber foam composite material could be widely used in the field of flame retardant materials due to its excellent flame retardancy.
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