Click Chemistry Reactions between Hydroxyl‐Terminated or Alkynyl‐Terminated Polybutadiene and Benzyl Azide

Abstract

AbstractAlkynyl‐terminated polybutadiene (ATPB) may be as a new type of propellant binder through click chemistry reaction between alkynyl and azide group. In this paper, The reactions between ATPB and hydroxyl‐terminated polybutadiene (HTPB) with benzyl azide, respecfively, were tracked by 1H‐NMR, 13C‐NMR, FTIR, and Elemental analysis measurements. The results show that the azide group and C=C of HTPB undergo 1,3‐dipolar cycloaddition reaction to form a 1,2,3‐triazoline ring without the catalyst. Both terminal C≡C and middle C=C bonds of ATPB can react with azide groups, and the reactivity of the C≡C bond is significantly higher than that of the C=C bonds. With the copper (I) catalyst, the reaction between the azide group and the C=C bonds of HTPB is significantly weakened, that is the copper (I) can not catalyze the reaction between C=C and ‐N3. these results are very meaningful for the design of the ATPB and azide system as the binder of solid propellant.