Studies On Preparation And Property Of DOPO Retarded Epoxy/CNTs Nanocomposites

MBTBA functionalized and PDA functionalized MWCNTs were prepared using simple ultrasonic process.Then epoxy/CNT composites, DOPO retarded epoxy resins and DOPO retarded epoxy/CNT composites were prepared using PDA as curing agents, their mechanical properties, thermal properties and flame-retardant properties were investigated.FT-IR and EDS analysis showed that there are some amine groups and carboxyl existed on the surface of MWCNTs after modification.Mechanical analysis showed that the tensile strength and bending strength of retarded samples was increased apparently with MBTBA functionalized MWCNTs, increasing by15%and24%respectively,compare to neat epoxy. After the addition of MBTBA functionalized MWCNTs, the impact strength of composites was increased by140%.DMA tests showed that Tg were decreased by4-6℃after adding0.5wt%MBTBA functionalized MWCNTs. DOPO has negative effect on Tg.FE-SEM tests showed that the dispersion of functionalized MWCNTs is better than that of unfunctionalized CNTs.TGA tests showed that the addition of DOPO can decrease the initial decomposition temperature as well as help the formation of char residue.CONE tests showed that CNT and DOPO have proper flame retardant effects, the sample which contains both DOPO and CNT has the best flame retardant effects, pkHRR was decreased by30.7%compare to neat epoxy, THR was decreased by22%.