One-pot synthesis of supramolecular polymer containing quadruple hydrogen bonding units

A facile, efficient technique was built to synthesize a supramolecular material containing quadruple hydrogen bonding sites. The current approach presented here involves a single-step reaction between the amine of precursor, e.g. methyl isocytosine (MIC) and the epoxy group of polymer, e.g. poly(ethylene glycol diglycidyl ether) (PEG DGE, M_n = 526 g/mol, as verified using ¹H NMR and FT-IR spectroscopy. Wide angle X-ray scattering (WAXS), UV/visible spectroscopy and differential scanning calorimeter (DSC) clearly show that the product is not a simple mixture of two components, but the supramolecular polymer containing quadruple hydrogen bonding sites. Complex melt viscosities reveal that mechanical properties of the supramolecular polymer are enhanced by more than 10⁴ times compared to the pristine low molecular weight polymer, giving rise to the significant change of physical state from liquid to solid. Current approach also illustrates an advantageous route because it does not need the selective use of monofunctionalized precursor and not produce a dead, difunctionalized precursor.