Liang Tianxiang, Cai Jianan, Liu Shumei, Lai Hualin, Zhao Jianqing
School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China.
Shenzhen Halcyon New Materials Co., Ltd., Shenzhen 518116, China.
Materials (Basel). 2019 Jul 10;12(14):2217. doi: 10.3390/ma12142217.
A way to suppress the deterioration in mechanical properties of polyamide 6 (PA6) is required, especially with high loading of flame retardants in the matrix. In this study, a novel aromatic Schiff base diepoxide (DES) was synthesized. It exhibited an efficient chain extension effect on PA6 and a synergistic flame-retardant effect with aluminum diethylphosphinate (AlPi) for PA6. The PA6 composite with 16 wt.% AlPi only passed UL-94 V-0 rating at 1.6 mm thickness, while the combination of 1.5 wt.% DES with 13 wt.% AlPi induced PA6 to achieve a UL-94 V-0 rating at 0.8 mm thickness. The tensile, flexural, and Izod notched impact strengths were increased by 16.2%, 16.5%, and 24.9%, respectively, compared with those of V-0 flame-retarded PA6 composites with 16 wt.% AlPi. The flame-retarded mechanism of PA6/AlPi/DES was investigated by cone calorimetry and infrared characterization of the char residues and pyrolysis products. These results showed that DES had a synergistic effect with AlPi in condensed-phase flame retardation by promoting the production of aluminum phosphorus oxides and polyphosphates in the char residues.
需要一种抑制聚酰胺6（PA6）机械性能恶化的方法，尤其是在基体中高负载阻燃剂的情况下。在本研究中，合成了一种新型芳香族席夫碱二环氧化合物（DES）。它对PA6表现出有效的扩链作用，并与二乙基次膦酸铝（AlPi）对PA6具有协同阻燃作用。仅含16 wt.% AlPi的PA6复合材料在1.6 mm厚度时仅通过UL-94 V-0等级，而1.5 wt.% DES与13 wt.% AlPi的组合使PA6在0.8 mm厚度时达到UL-94 V-0等级。与含16 wt.% AlPi的V-0级阻燃PA6复合材料相比，拉伸强度、弯曲强度和悬臂梁缺口冲击强度分别提高了16.2%、16.5%和24.9%。通过锥形量热法以及对残炭和热解产物的红外表征研究了PA6/AlPi/DES的阻燃机理。这些结果表明，DES通过促进残炭中铝磷氧化物和聚磷酸盐的生成，在凝聚相阻燃中与AlPi具有协同作用。
