A novel bio-based AB2 monomer for preparing hyperbranched polyamides derived from levulinic acid and furfurylamine†
A new AB2 type bio-based monomer (FDA-E) with two amino functional groups and one ester functional group was prepared from renewable levulinic acid and furfurylamine using a three-step reaction. The AB2 monomer underwent self-polycondensation under melt conditions to form a hyperbranched bio-polyamide. Polyamides show excellent solubility in a strong polar solvent and acidic solution. In pure water, the rigid polyamides form a stable elastic gel by absorbing water instead of dissolving in it. Their glass transition temperatures are in the range 97–102 °C and their char yields at 800 °C are greater than 40%. The XRD results indicate that the three polyamides are amorphous polymers. In addition, the hyperbranched polyamides are fluorescent polymers and their photoluminescence properties depend on molecular weight, solvent, excitation wavelength, and excitation time.