Liu Botong, Jin Gaoling, Dong Zhenfeng, Zhang Xiuqin, Zhu Zhiguo, Bing Linhan, Ma Chaohui, Wei Jianfei, Wang Rui
School of Materials Design and Engineering, Beijing Institute of Fashion Technology, East Yinghua street, Chaoyang District, Beijing 100029, China.
China Chemical Fibers Association, 18 Chaoyangmen North Street, Chaoyang District, Beijing 100020, China.
ACS Omega. 2025 Jul 5;10(27):29856-29865. doi: 10.1021/acsomega.5c04482. eCollection 2025 Jul 15.
Polyhexamethylene adipamide (PA66), a prominent engineering thermoplastic and chemical fiber material, plays a crucial role in industrial applications and daily life. However, its inherent flammability accompanied by substantial heat release during combustion presents significant fire safety hazards. To address this limitation, we developed a reactive flame-retardant modification strategy using 4-formylbenzeneboronic acid (FBA) through simple melt blending with PA66. It is revealed that incorporating 4 wt % FBA effectively enhanced the flame retardancy, achieving a limiting oxygen index (LOI) of 28%. Notably, this formulation demonstrated a 49.9% reduction in peak heat release rate (pHRR) and an 8.3% decrease in total heat release (THR) compared with pristine PA66. Mechanistic investigations indicated that FBA primarily functions via condensed-phase flame retardation. Specifically, FBA facilitates the formation of a compact carbonaceous char with improved structural regularity and graphitization degree. This enhanced char layer architecture effectively impedes heat and oxygen transfer while exhibiting superior thermal shielding capability and structural stability.
聚己二酰己二胺（PA66）是一种重要的工程热塑性塑料和化学纤维材料，在工业应用和日常生活中发挥着关键作用。然而，其固有的可燃性以及燃烧过程中大量的热释放带来了重大的消防安全隐患。为了解决这一局限性，我们通过与PA66简单熔融共混，采用4-甲酰基苯硼酸（FBA）开发了一种反应性阻燃改性策略。结果表明，加入4 wt%的FBA有效地提高了阻燃性能，极限氧指数（LOI）达到28%。值得注意的是，与原始PA66相比，该配方的热释放峰值速率（pHRR）降低了49.9%，总热释放（THR）降低了8.3%。机理研究表明，FBA主要通过凝聚相阻燃起作用。具体而言，FBA促进形成具有改善的结构规整性和石墨化程度的致密碳质焦炭。这种增强的焦炭层结构有效地阻碍了热和氧的传递，同时表现出优异的热屏蔽能力和结构稳定性。
