碳纳米管与蒙脱土在尼龙6阻燃中的协同效应

The Synergistic Effects Between Carbon Nanotubes and Montmorillonite in Enhancing the Flame Retardancy of Polyamide 6

纳米技术为聚合物阻燃提供了新思路,以碳纳米管(CNT)和有机改性蒙脱土(MMT)为阻燃剂,通过两者之间的协同效应改善尼龙6(PA6)的阻燃性能。通过熔融共混法制备了尼龙6/碳纳米管/蒙脱土纳米复合材料,系统研究了碳纳米管与蒙脱土在改善尼龙6阻燃性能时的协同效应,并通过炭层结构、微观形貌、热稳定性等对两者的协同机理进行分析。结果表明,当添加4%的碳纳米管和1%的蒙脱土时,PA6的氧指数由22.0%提高到了24.5%,热释放速率峰值由1 000.2 kW/m^2降低到421.1 kW/m^2;碳纳米管和蒙脱土可以提高尼龙6的热稳定性和最终的残炭量,而且,碳纳米管对PA6还有增强作用,主要在固相中发挥协同阻燃作用。

Nanotechnology provided new opportunities for improving the flame retardancy of polymers. The flame retardaney of polyamide 6 （PA6） was enhanced by the synergistic effect between carbon nanotubes （CNT） and organic montmorillonite （MMT）. Nylon 6/carbon nanotubes/montmorillonite nanocomposite was prepared by melt blending method. The synergistic effect of carbon nanotubes and montmorillonite on the flame retardaney of nylon 6 was studied systematically. The appearance and thermal stability of the two mechanisms were analyzed. The research results showed that optimal flame retardant＇ properties could be obtained at the presence of only 4% CNT and 1% MMT. The limiting oxygen index reached from 22.0% up to 24.5% , and the peak heat release rate decreased from 1 000.2 kW/m^2 to 421.1 kW/m^2. Carbon nanotubes and montmorillonites could improve the thermal stability and the final amount of carbon residue of nylon 6, and carbon nanotubes could also enhance PA6. The amount of residue char increased after loaded with CNT and MMT, which mainly took effects in condensed phase.