AbstractA click reaction of aromatic polyimide having azide groups at both chainends (2), which was obtained by an azidation of polyimide having chloromethyl groups (1), was conducted with 1-octyne, leading to the polyimide having n-hexyl groups (3). 1H NMR spectroscopic analysis for 3 reveals that the n-hexyl groups were successfully introduced into the both chain-ends of aromatic polyimide and that a number-averaged molecular weight of the resulting polymer 3 was 6000. Differential scanning calorimetry analysis for 3 exhibited 30 °C lower glass transition temperature compared to that of 1, by introducing long alkyl groups into the aromatic polyimide chain.