A series of flame-retardant waterborne polyurethane (AWPU-X) compounds with core–shell structures were synthesized by encapsulating hexaphenoxycyclophosphazene (HPCTP) with WPU. AWPU-X, melamine (MA), and AO₁₀D₃-WPU (a flame-retardant WPU self-made in the lab) were synergistically used to prepare flame-retardant microfiber synthetic leather by a two-step method, and the relevant properties of AWPU-X and the microfiber synthetic leather were characterized. The results showed that AWPU-X formed a core–shell structure and had good emulsion stability and film thermal properties. The limiting oxygen index (LOI) value of AWPU-11 reached 27.5% when the HPCTP addition was 11% by mass. The mechanical properties of the flame-retardant microfiber synthetic leather were improved, while the hand-feel of the leather was not affected. When the mass ratio of AWPU-11/MA/AO₁₀D₃-WPU was 60 : 20 : 20, the flame retardancy of the microfiber synthetic leather was the best, with the LOI value of 27.6%, no after-flame, and a damage length of only 0.5 cm in the vertical flame test. At the same time, the peak heat release rate (PHRR) and total heat release (THR) in the cone calorimeter test were reduced by 42% and 30%, respectively. Although the introduction of flame-retardant components decreased the thermal performance of the microfiber synthetic leather, the thermal decomposition residual carbon rate was significantly improved. Based on the results of SEM-EDS, TG-IR, and Raman tests, it was speculated that the flame retardancy of the microfiber synthetic leather was primarily attributed to the joint action of the flame-retardant components in both the gas and condensed phases.

中文翻译：

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核壳结构阻燃水性聚氨酯的制备及其在阻燃超细纤维合成革中的应用


通过将六苯氧基环磷腈（HPCTP）与WPU封装，合成了一系列具有核壳结构的阻燃水性聚氨酯（AWPU-X）化合物。 AWPU-X、三聚氰胺（MA）和AO ₁₀ D ₃ -WPU（实验室自制的阻燃WPU）协同制备阻燃微纤维采用两步法制备合成革，并对AWPU-X和超细纤维合成革的相关性能进行表征。结果表明，AWPU-X形成核壳结构，具有良好的乳液稳定性和薄膜热性能。当HPCTP添加量为11质量%时，AWPU-11的极限氧指数（LOI）值达到27.5%。阻燃超细纤维合成革的机械性能得到改善，同时皮革的手感不受影响。当AWPU-11/MA/AO ₁₀ D ₃ -WPU质量比为60:20:20时,超细纤维合成革的阻燃性能最好, LOI值为27.6%，无余焰，垂直火焰测试损伤长度仅为0.5厘米。同时，锥形量热仪测试中的峰值放热量（PHRR）和总放热量（THR）分别降低了42%和30%。阻燃成分的引入虽然降低了超细纤维合成革的热性能，但热分解残碳率却得到显着提高。根据SEM-EDS、TG-IR和拉曼测试结果推测，超细纤维合成革的阻燃性主要归因于气相和凝聚相阻燃组分的共同作用。