Bachtiar Erik Valentine, Kurkowiak Katarzyna, Yan Libo, Kasal Bohumil, Kolb Torsten
Centre for Light and Environmentally-Friendly Structures, Fraunhofer Wilhelm-Klauditz-Institut WKI, Bienroder Weg 54E, Braunschweig 38108, Germany.
Department of Organic and Wood-Based Construction Materials, Technical University of Braunschweig, Hopfengarten 20, 38102 Braunschweig, Germany.
Polymers (Basel). 2019 Apr 16;11(4):699. doi: 10.3390/polym11040699.
In this study, ammonium polyphosphate (APP) and aluminum hydroxide (ALH) with different mass contents were used as fire retardants (FRs) on plant-based natural flax fabric-reinforced polymer (FFRP) composites. Thermogravimetric analysis (TGA), limited oxygen index (LOI), and the Underwriters Laboratories (UL)-94 horizontal and vertical tests were carried out for evaluating the effectiveness of these FR treatments. Flat-coupon tensile test was performed to evaluate the effects of FR treatment on the mechanical properties of the FFRP composites. For both fire retardants, the results showed that the temperature of the thermal decomposition and the LOI values of the composites increased as the FR content increases. Under the UL-94 vertical test, the FFRP composites with 20% and 30% APP (i.e., by mass content of epoxy polymer matrix) were self-extinguished within 30 and 10 s following the removal of the flame without any burning drops, respectively. However, the mechanical tensile tests showed that the APP treated FFRP composites reduced their elastic modulus and strength up to 24% and 18%, respectively. Scanning electronic microscopic (SEM) for morphology examination showed an effective coating of the flax fibres with the FRs, which improved the flame retardancy of the treated composites.
在本研究中，采用不同质量含量的聚磷酸铵（APP）和氢氧化铝（ALH）作为植物基天然亚麻织物增强聚合物（FFRP）复合材料的阻燃剂（FRs）。进行了热重分析（TGA）、极限氧指数（LOI）以及美国保险商试验所（UL）-94水平和垂直试验，以评估这些阻燃处理的有效性。进行了平板试样拉伸试验，以评估阻燃处理对FFRP复合材料力学性能的影响。对于两种阻燃剂，结果表明，随着阻燃剂含量的增加，复合材料的热分解温度和极限氧指数值均升高。在UL-94垂直试验中，含20%和30%APP（即占环氧聚合物基体的质量含量）的FFRP复合材料在火焰移除后分别在30秒和10秒内自行熄灭，且无任何燃烧滴下。然而，力学拉伸试验表明，经APP处理的FFRP复合材料的弹性模量和强度分别降低了24%和18%。用于形态学检查的扫描电子显微镜（SEM）显示，阻燃剂有效地包覆了亚麻纤维，提高了处理后复合材料的阻燃性。
