Thermal Stability and Flame Retardancy of Polypropylene/NiAl Layered Double Hydroxide Nanocomposites

NiAl layered double hydroxide (NiAl-LDH) was synthesized by co-precipitation method. And sodium dodecyl sulphate (SDS) as modifier was utilized to enlarge the d-spacing of NiAl-LDH to obtain SDS-NiAl-LDH. PP/SDS-NiAl-LDH nanocomposites were prepared with different amount of SDS- NiAl-LDH and PP by melt intercalation method. The results of XRD and TEM confirmed that intercalated and exfoliated-intercalated structures were formed. Compared with pure PP, PP/SDS- NiAl-LDH nanocomposites exhibited high thermal stability and residual to the presence of barrier effect of NiAl-LDH layers. Cone calorimetry analysis indicated that incorporation of SDS-NiAl-LDH obviously improved flame retardancy and smoke suppression properties of PP. With the addition of 5 wt% SDS-NiAl-LDH, the peak heat release rate (PHRR), the total heat release (THR) and smoke production rate (SPR) peak values reduced 32.4%, 16.0%, and 61.5% compared with those of pure PP, which were attributed to the barrier effect and excellent charing performance of SDS-NiAl-LDH.