Synthesis of polyamide dendrons bearing pyridine groups as multiple hydrogen bonding parts on the periphery

Abstract

Aromatic polyamide dendrons (G0-G2) having amino groups on the periphery were prepared by divergent method. Reaction of GO aromatic polyamide dendron with isonicotinoyl chloride hydrochloride gave polyamide dendron (G0-2Py) bearing two pyridine groups. The structures of polyamide dendrons were confirmed by IR, H-1, C-13 NMR, MALDI-TOF mass spectroscopy. A hydrogen-bonded G0-2Py/poly(acrylic acid) (PAA) 1/2 complex was prepared by mixing G0-2Py with PAA in methanol, followed by removing the solvent. IR spectrum of G0-2Py/PAA 1/2 complex showed characteristic absorptions at 2550 and 1950cm(-1) due to hydrogen bonding. A glass transition temperature (T-g) of G0-2Py/PAA 1/2 complex was observed at 121 degreesC by DSC measurement, whereas T(g)s of G0-2Py (137degreesC) and PAA (87degreesC) disappeared. T-g of the G0-2Py/PAA complex was dependent on the molar ratio ([Donor]/ [Acceptor]). Maximum T-g at 121 degreesC was observed at a ratio of 1.