Study On Interfacial Compatibility And Thermal Degradation Of Zn-MpolyP Flame Retarded And Glass Fiber Reinforced PA66 Composites

Nowadays, composites already are indispensable material in national economy and daily life, and the research of glass fiber reinforced composites is the most perfect, at the same time the application of composites reinforced glass fiber is also most broad. Glass fiber reinforced PA66 has more practical applications, such as automobile, electric, electronic etc, due to enhanced softening point and mechanical performance. But the glass fiber reinforced nylon was quite difficult to flame retardanted because of the "candlewick effect" of the glass fibers. Traditional halogen-containing flame retardant and glass fiber reinforced nylon is very important, but it was bad for environment, and released noxious air at burning. Therefore, the research of halogen-free flame retardant glass fiber reinforced nylon is very important. In order to improve the high-performance of halogen-free flame retardant glass fiber reinforced nylon, the interfacial interaction and compatibility are most important, issues that researchers have been paied attention to.In the paper, the flame retarded and glass fiber reinforced PA66 composites(PA66/GF/FR) were prepared with glass fiber and the flame retardant of (MpolyP) or Zn-MpolyP. The Morphological structures, mechanical properties, crystallization and melting behavior, thermal degradation behavior, and Surface properties of the components of the composites were studied. According to the results, the interfacial interaction and compatibility of PA66/GF/FR were discussedSurface properties of the components of the composites were analyzed by inverse gas chromatography (IGC).The results show that the sorption of Lewis acid-base is stronger between Zn-MpolyP and nylon 66 or Glass fiber than MpolyP and nylon 66 or Glass fiber. This result is probably due to the strong complex between Zn²⁺ in Zn-MpolyP and lone pair electrons at O and N atoms of PA66 and Glass fiber.The mechanical properties of flame retarded and glass fiber reinforced PA66 composites were investigated. The results show that the tensile strength, flexural strength and Notched Izod impact strength of Zn-MpolyP flame retarded and glass fiber reinforced PA66 composites (PA66/GF/Zn-MpolyP) were much higher than these of MpolyP flame retarded and glass fiber reinforced PA66 composites(PA66/GF/MpolyP).Morphological structures of the flame retarded and glass fiber reinforced PA66 composites were observed by SEM. The results show the interfacial interaction and compatibility between PA66 and glass fiber were not good. However the flame retardants, MpolyP and Zn-MpolyP, could obviously improve the interfacial interaction and compatibility between PA66 and glass fiber. The effect of Zn-MpolyP was much better than that of MpolyP. The non-isothermal crystallization of PA66/GF/FR were investigated by DSC. The results show that MpolyP and Zn-MpolyP could clearly enhance the enthalpy (â–³H_c) and temperature(T_C) of PA66 crystallization in the composites, because the flame retardants present the good nucleation function in PA66. The enthalpy (â–³AH_c) of PA66 crystallization in PA66/GF/Zn-MpolyP was higher than that in PA66/GF/MpolyP. It further proved that the flame retardants, especially Zn-MpolyP, could improve the interfacial interaction and compatibility among components in the composites.The thermal degradation behavior of PA66/GF/FR composites was studied by thermal gravimetric analysis (TGA). The results show that the flame retardants of MpolyP and Zn-MpolyP changed the thermal degradation behavior of PA66, and improved the char residue formation. The T_initial , T_1peak and T_2peak of Zn-MpolyP flame retarded and glass fiber reinforced PA66 composites(PA66/GF/ Zn-MpolyP) were higher than MpolyP flame retarded and glass fiber reinforced PA66 composites(PA66/GF/ Zn-MpolyP).