基于聚磷酸铵的乙烯基酯树脂的阻燃机理研究

乙烯基酯树脂(VER)因其具有良好耐腐蚀性能和优异的物理性能被广泛应用于诸多领域,然而由于VER极易燃,限制了其使用范围.为了提高VER的阻燃性,本文将聚磷酸铵(APP)作为阻燃剂引入VER中,制备得到阻燃乙烯基酯树脂固化物;采用热重分析仪(TGA)表征了VER的热稳定性;扫描电子显微镜(SEM、SEM-EDX)研究了VER燃烧后残炭的微观形貌,表面元素组成及分布;利用极限氧指数(LOI)、垂直燃烧测试(UL-94)、锥形量热(CCT)对其阻燃性能进行测试;采用热重红外光谱联用仪(TG-FTIR)等手段分析APP在VER中的阻燃机理.研究结果表明,当APP的引入量为30 wt%时,乙烯基酯树脂的极限氧指数达到30.3%,通过UL-94 V-0级别. APP在凝聚相和气相中共同发挥阻燃作用.

Research on the flame retardant mechanism of vinyl ester resin based on ammonium polyphosphate

Vinyl ester resin (VER) is a widely used material due to its good corrosion resistance and excellent physical properties. However, its extreme flammability limits its use in many fields. To improve the flame retardancy of VER, the authors of this paper introduce ammonium polyphosphate (APP) as a flame retardant, and prepare flame retardant cured vinyl ester resin. The following methods are used to test the flame retardant properties of the prepared compounds: thermogravimetric analyzer (TGA) to characterize thermal stability; scanning electron microscope (SEM, SEM-EDX) to investigate the microscopic morphology, composition and distribution of surface elements of residual carbon after burning of VER; limiting oxygen index (LOI), vertical burning test (UL-94), and cone calorimetry (CCT) to test the flame retardant properties; thermogravimetric infrared spectrometer (TG-FTIR) to analyze the flame retardant mechanism of APP in VER. The results show that when the content of APP reaches 30 wt%, the limiting oxygen index of vinyl ester resin reaches 30.3%, and passes the UL-94 V-0. APP plays a flame retardant role in both condensed phase and gas phase together.