Preparation of Hydroxyl-Terminated Polybutadiene by the Pyrolysis Method and Its Application in Polyurethane

Hydroxyl-terminated polybutadiene with a high cis -1,4 content ( cis -HTPB) was prepared by direct oxidative cracking of cis -polybutadiene rubber (BR-9000) with periodic acid (H 5 IO 6 ). The results showed that the cis -HTPB structure contained more than 95% of the cis -1,4 structure, and the glass transition temperature ( T g ) was as low as −104.7 °C, exhibiting excellent low-temperature resistance. In addition, the optimal reaction conditions were determined by optimizing the preparation process to achieve efficient and controllable preparation of cis -HTPB. Finally, polyurethane elastomers were prepared based on cis -HTPB, and the mechanical properties of the elastomers were improved by optimizing the formulation design. The tensile strength of the elastomers was as high as 1.84 MPa and the elongation at break was 721%, which can meet the requirements of different applications. This study provides a simpler strategy for the oxidative degradation of cis -polybutadiene rubber to prepare high-value-added cis -HTPB and also provides experience for the functionalization of other types of polyolefin rubbers.