温敏性水凝胶制备及阻燃性能研究

Preparation and flame retardant properties of temperature-sensitive hydrogels

采用甲基纤维素(MC)、聚乙二醇(PEG)、氯化钠(NaCl)为原料制备温敏性水凝胶,并在该体系中添加阻燃剂聚磷酸铵(APP),优选出材料体系质量分数配比为MC∶PEG∶NaCl∶APP=1.3∶5.0∶5.0∶1.5。采用试管倒置法测得其LCST为58℃。利用傅里叶红外光谱仪(FT-IR)表征产物结构,借助热重分析仪和锥形量热仪分别测试水凝胶的热稳定性以及阻燃性能。实验结果显示,材料配比组分体系没有发生化学作用。对比未处理和水浸泡过的木板,经温敏性水凝胶浸泡后的木板点燃时间和热释放速率峰值出现时间均明显延迟。与未处理木板相比,经温敏性水凝胶浸泡后的木板点燃时间延迟76 s,第一次和第二次热释放速率峰值出现时间分别延迟83 s和269 s,表明制备的温敏性水凝胶具有良好的阻燃性能。

The temperature-sensitive hydrogels were prepared by methyl cellulose(MC),polyethylene glycol(PEG)and sodium chloride(NaCl)as raw materials,and the flame retardant ammonium polyphosphate(APP)was added to this system.The mass fraction ratio of the material system was optimized as MC∶PEG∶NaCl∶APP=1.3∶5.0∶5.0∶1.5.LCST was measured at 58℃by tube inversion method.The structure of hydrogels was characterized by Fourier infrared spectroscopy(FT-IR),and the thermal stability and flame retardancy of hydrogels were measured by thermal gravimetric analysis(TG)and cone calorimeter.Experimental results showed that there is no chemical action in the mixture system of materials.Comparing with untreated boards and water-soaked boards,the initiation time and peak occurrence time of the heat release rate of the board soaked in the temperature-sensitive hydrogel were significantly delayed.Compared with untreated wood,the ignition time of wood boards immersed in temperature-sensitive hydrogel was delayed by 76 s,the peak time of the first and second heat release rate was delayed by 83 s and 269 s,respectively,indicating that the temperature-sensitive hydrogel under the preparation system had good flame retardant performance.