Poly(amide-imide)/organoclay nanocomposites using glycine as a natural amino acid: study on fire and thermal behavior

Abstract

In the present study, new functional poly(amide-imide)/organoclay nanocomposite films were successfully fabricated through the solution intercalation technique. New poly(amide-imide) (PAI) containing glycine was synthesized via solution polycondensation of 1,1',3,3'-tetraoxo(5,5'-biisoindoline-2,2'-diyl)diacetic acid with 4,4′-diaminodiphenylsulfone. The synthesized PAI was characterized by 1H NMR, Fourier transform infrared (FTIR) spectroscopy, gel permeation chromatography, elemental analysis and inherent viscosity. Then, PAI/organoclay nanocomposite films containing 4 and 8 wt% of organoclay were prepared via solution intercalation through blending of organoclay 30B with the PAI solution. The nanostructures and properties of the PAI/organoclay were investigated using FTIR spectroscopy, XRD, transmission electron microscopy (TEM), TGA, DSC and microscale combustion calorimetry. XRD and TEM revealed the good dispersion of organoclay in the polymer matrix. TGA indicated that the addition of organoclay into the PAI matrix increases the thermal decomposition temperatures and char yields of the nanocomposites. Organoclay shows a positive effect in improving the flame retardancy of the PAI, reflecting the decrease in heat release rate, the total heat release and the heat release capacity of the PAI nanocomposites, while the thermal stability of the PAI nanocomposites only increased slightly compared with the neat polymer. © 2013 Society of Chemical Industry