Effect of MMT on Flame Retardancy of PLA/IFR/LDH Composites

Nano filler synergistic intumescent flame retardant (IFR) system is an effective way to improve the flame retardant properties of polymer. In this study, the effects of montmorillonite (MMT) on the flame retardant properties of polylactic acid/layered double hydroxides (PLA/LDH) and PLA/IFR/LDH were investigated. The results show that both LDH and LDH/IFR can reduce the peak heat release rate (HRR) of PLA and prolong the combustion time of PLA; When a proportionate MMT is introduced into PLA/LDH and PLA/IFR/LDH systems, respectively, MMT will not only affect the degradation process of PLA composites during combustion, but also the PLA composites can form a more stable carbon layer during combustion, which could decrease the peak HRR and prolong combustion time of PLA composite. Furthermore, when 0.5 wt% MMT is incorporated, the peak HRR of LDH/ IFR/LDH composite is reduced by 16.17% and the combustion time is prolonged by about 70 s. This study can provide an opportunity to further optimize the properties of intumescent flame retardant polymer.