A novel synthetic strategy for hydroxyl-terminated polybutadiene containing high cis -1,4 contents based on a Ni(ii)-coordinated anionic initiating system.

In this study, novel hydroxyl-terminated polybutadiene (HTPB) with a high cis -1,4 content was developed using a tert -butyl dimethyl siloxy dimethyl propyl lithium (Li)-naphthenate nickel (Ni)-boron trifluoride (B) initiating system (Li-Ni-B). The effects of the material ratio and the addition sequence on the cis -1,4 content and molecular weight of HTPB were studied, and the results were discussed. The optimal Li/Ni ratio was 10 : 1, and the optimal Li/B ratio was 1 : 2. HTPB prepared by the Li-Ni-B system was characterized by Fourier transform infrared spectroscopy (FTIR), 1 H nuclear magnetic resonance ( 1 H-NMR) spectroscopy, and 13 C nuclear magnetic resonance ( 13 C-NMR) spectroscopy. The results suggested high cis -1,4 contents in HTPB synthesized using Li-Ni-B ( cis -1,4 > 95%). The comparison of the cis -1,4 contents in the HTPB samples obtained by anionic polymerization and the Li-Ni-B system revealed the advantages of the latter compared to the former.