Improving Flame Retardancy of Epoxy Resin Nanocomposites by Carbon Nanotubes Grafted CuAI-Layered Double Hydroxide Hybrid

To solve the issues of the poor dispersion performance of the inorganic flame retardant filler in epoxy resin (EP) matrix, the three-dimensional (3D) hybrid carbon nanotubes-copper aluminum (sodium dodecyl sulfate) -layered double hydroxide (CNTs-OLDH) is designed and synthesized by co-precipitation. The results indicate that the CNTs-OLDH hybrid with 3D-structure is successfully fabricated and well dispersed in EP matrix. The thermostability of EP/CNTs-OLDH nanocomposites is raised and the residue is obviously increased. When the amount of CNTs-OLDH is only 4 wt%, limit oxygen index value of EP/CNTs-OLDH nanocomposites reaches 28.5. Compared with pure EP, the heat release, smoke and gas of EP/FePP nanocomposites are inhibited by CNTs-OLDH hybrid, and the PHRR, THR and SPR values of EP/4CNTs-OLDH nanocomposites decrease by 41.7%, 27.8% and 31.7%. The improved fire retardant performances and thermal stability are attributed to the excellent homogeneous dispersion, the network structure formed by the 3D hybrid in the matrix and the outstanding flame retardant effect of CNTs and OLDH.