Synthesis and characterization of self-coloured polyamide nanocomposites containing azo group reinforced with magnesium hydroxide nanoparticles

In this work, self-coloured nanocomposites containing Azo functional groups based on polyamide (PA) reinfoced with surface modified magnesium hydroxide nanoparticles were prepared, and their structure and properties were investigated. PA was synthesized by direct polycondensation and its structure confirmed by FTIR and NMR. The solubility test results indicated that the synthesized PA easily dissolved in aprotic organic solvents such as dimethyl formamide (DMF) at room temperature. Modified magnesium hydroxide nanoparticles (MMH) were prepared via two steps including coprecipitation reaction and then surface modification in the presence of azo dicarboxylic acid. Nanocomposites (PAN) were prepared with PA and appropriate amounts of MMH via casting solution method. The results of XRD and FE-SEM indicated that nanoparticles were uniformly dispersed in the PA matrix. Thermal properties of PA and related nanocomposites were studied by using thermogravimetric analysis (TGA). According to TGA results, MMH had a good effect on the thermal stability of polyamide. With addition of 8 mass% of modified nanoparticles in the PA matrix, T5 and T10 values increased 30ᵒC.