Abstract
Hyperbranched aromatic polyamides from 3,5-diaminobenzoic acid and G1 aromatic polyamide dendrons with terminal phenylethynylphthalimide groups were synthesized, and solubility and thermal properties of the resulting polymers were examined. Molecular weights of the resulting hyperbranched polyamides could be controlled by the copolymerization of 3,5-diaminobenzoic acid and m-phenylenediamine. All resulting polymers with imide groups were soluble in aprotic polar solvents such as DMAc and NMP. Tgs of the polymers having phenylethynyl groups cured at 370°C for 1h were not detected below 400°C by DSC. Thermal decomposition temperatures of the polymers with terminal imide groups were higher than those of terminal amino groups and benzamide groups. Furthermore, and the first generation (G1) polyamide dendrons having phenylethynyl groups and the additive polyimide “TriA-PI”, which was prepared from 2,3,3’,4’-biphenyltetracarboxylic anhydride, 4,4’-oxydianiline and 4-phenylethynylphthalic anhydride, were blended and cured. The blends had good processability and clear films were obtained. The blends of the additive polyamide dendrons exhibited higher Tg than that of TriA-PI. However, the elongation at break was decreased with the increase in the ratio of the polyamide dendrons.
