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采用高温化学发泡法制备了一种间乙炔基苯偶氮酚醛树脂泡沫(EPANF).采用傅里叶红外光谱(FTIR)、凝胶渗透色谱(GPC)、光学显微镜、扫描电子显微镜(SEM)、导热系数分析仪、临界氧指数分析仪和热重分析(TG)等表征了间乙炔基苯偶氮酚醛树脂(EPAN)结构和EPANF的泡孔结构、压缩强度、隔热性能、阻燃性能和热性能.研究结果表明,当所用发泡剂含量为18%,泡沫体的表观密度为0.179 g/cm~3时,EPANF泡孔均匀微细,闭孔率高,泡孔平均粒径为350μm左右.随着表观密度增加,泡沫体压缩强度增大,热导率系数增大,隔热性能略有下降,但其临界氧指数变大,阻燃性能提高.当表观密度为0.363 g/cm~3时,EPANF的压缩强度达到最大为5.63 MPa.EPANF的5%和10%热失重温度分别为333、381℃,其700℃的残炭率和1000℃的残炭率分别为65.8%和58.2%,耐热性和耐烧蚀性较普通线性酚醛树脂有明显提高.EPANF作为热结构材料和烧蚀材料有望在航天航空等领域应用.
An EPANF foam was prepared by high temperature chemical foaming method.FTIR, GPC, optical microscope and scanning electron microscope (SEM) , Thermal conductivity analyzer, critical oxygen index analyzer and thermogravimetric analysis (TG) were used to characterize the cell structure, compressive strength, thermal insulation and flame retardancy of EPANF and EPANF And thermal properties.The results show that when the content of foaming agent is 18% and the apparent density of foams is 0.179 g / cm ~ 3, EPANF cells are even and fine, the closed cell ratio is high, the average cell size is 350μm.With the increase of apparent density, the compressive strength of foam increased, the coefficient of thermal conductivity increased, the thermal insulation performance decreased slightly, but the critical oxygen index became larger and the flame retardancy increased.When the apparent density was 0.363 g / cm ~ 3, the maximum compressive strength of EPANF is 5.63 MPa.The 5% and 10% weight loss temperatures of EPANF are 333 and 381 ℃, respectively.The residual char yield at 700 ℃ and the char yield at 1000 ℃ are 65.8% and 58.2%, heat resistance and ablation resistance than the average phenolic resin has significantly improved.EPANF as a thermal structure Materials and ablative materials is expected in aerospace and other applications.