论文部分内容阅读
To minimize the loading level of the char-forming phosphorus based flame retardants in the poly(lactic acid)(PLA) with reduced flammability, we have developed the flame-retarded PLA nanocomposites by melt blending method incorporating organically modified montmorillonite(OMMT) and aluminium diethylphosphinate(AlPi) additives. The influence of AlPi and OMMT on flame retardancy and thermal stability of PLA was thoroughly investigated by means of the limiting oxygen index(LOI), UL94 test, cone calorimeter, X-ray diffraction(XRD), thermogravimetric analysis and scanning electronic microscopy(SEM). The experimental results show that the PLA/AlPi/OMMT system has excellent fire retardancy.The LOI value increases from 19% for pristine PLA to 28% for the flame-retarded PLA. Cone calorimeter analysis of the PLA/AlPi/OMMT exhibits a reduction in the peak heat release rate values by 26.2%. Thermogravimetric analysis and SEM of cone calorimeter residues indicate that OMMT significantly enhances the thermal stability, promotes char-forming and suppresses the melt dripping. The research of this study implies that the combining of the flame retardant and organoclay results in a synergistic effect. In addition, the flame-retarded PLA nanocomposite also exhibits notable increase in the impact strength and the elongation at break.
To minimize the loading level of the char-forming phosphorus based flame retardants in the poly (lactic acid) (PLA) with reduced flammability, we have developed the flame-retarded PLA nanocomposites by melt blending method incorporating organically modified montmorillonite (OMMT) and aluminum The influence of AlPi and OMMT on flame retardancy and thermal stability of PLA was thoroughly investigated by means of the limiting oxygen index (LOI), UL94 test, cone calorimeter, X-ray diffraction (XRD), thermogravimetric analysis The experimental results show that the PLA / AlPi / OMMT system has excellent fire retardancy. The LOI value increases from 19% for pristine PLA to 28% for the flame-retarded PLA. Cone calorimeter analysis of the PLA / AlPi / OMMT exhibits a reduction in the peak heat release rate values by 26.2%. Thermogravimetric analysis and SEM of cone calorimeter residues indicate that OMMT significantly enhances the thermal stability, promotes char-forming and suppresses the melt dripping. The research of this study implies that the combining of the flame retardant and organoclay results in a synergistic effect. In addition, the flame-retarded PLA nanocomposite also exhibits not not increase in the impact strength and the elongation at break.