聚磷腈改性沸石咪唑酯骨架材料的制备及其在聚酯阻燃中的应用

为提高聚对苯二甲酸乙二醇酯(PET)的阻燃性能,以六水合硝酸锌和2-甲基咪唑制备沸石咪唑酯骨架材料(ZIF-8),之后用六氯环三磷腈和4,4 -二羟基二苯砜对ZIF-8进行表面修饰合成一种ZIF-8聚环三磷睛-共磺酰基双酰/(PZS)亚微米颗粒,并与PET通过熔融共混制备PET阻燃复合材料。借助热重分析仪、极限氧指数仪、垂直燃烧仪、万能材料试验机以及扫描电镜等对复合材料的热稳定性、阻燃抗熔滴性、力学性能以及阻燃机制进行分析。结果表明:添加6%的ZIF-8/PZS亚微米颗粒使PET的极限氧指数(LOI值)提高到29.2%,并通过UL-94 V-0等级,而复合材料的力学性能没有受到严重影响;ZIF-8/PZS可以在气相和凝聚相中同时发挥效用,从而赋予PET复合材料优异的阻燃性能。

Preparation and application of polyphosphazene modified zeolite imidazolate framework materials for flame retardancy of poly(ethylene terephthalate)

In order to improve the flame retardancy of poly (ethylene terephthalate) (PET), a zeolite imidazolate framework material (ZIF-8) was fabricated from zinc nitrate hexahydrate and 2-methylimidazole. The surface of ZIF-8 were modified with hexachlorocyclotriphosphazene and 4,4-dihydroxydiphenylsulfone to synthesize a ZIF-8/PZS submicron particle. PET flame-retardant composites were prepared by melt blending with PET and their flame-retardant properties were investigated. Thermogravimetric analyzer, limiting oxygen index meter, vertical combustion meter, material testing machine and scanning electron microscope were used to analyze the thermal stability, flame retardancy, melt-dripping resistance, mechanical properties and flame-retardant mechanism of composite materials. The results show that the addition of 6% ZIF-8/PZS submicron particles increases the LOI value of PET to 29.2% and passes UL-94 V-0 level. The mechanical properties of the composite materials are not severely affected. ZIF-8/PZS can be effective in both the gas phase and the condensed phase, thereby giving PET composites excellent flame-retardant properties.