Rigid-rod aramids incorporating polymethylated monomers

The design and synthesis of a series of aromatic polyamides incorporating aminobenzoyl-, aminobenzoyl- and aminophenoxy-derivatives of durene (1,2,4,5-tetramethylbenzene) is described. A number of these polyaramids exhibited good solubility in polar organic solvents. Solutions of these polyaramids were amorphous exhibiting no lyotropic liquid crystalline behaviour. Proton nuclear magnetic resonance (NMR), carbon-13 NMR, and nuclear overhauser effect spectroscopy (NOESY) were used to investigate the structure of these polymers. The physical properties of these polyaramids were determined by differential scanning calorimetry (DSC), thermogravimetry (TG) and X-ray diffraction (XRD).