Hydroxyl-terminated polybutadiene (HTPB) is a liquid rubber with a long non-polar carbon chain. Because of its low glass transition temperature, high elasticity, high water resistance, and hydrophobicity, HTPB is widely used in adhesives, foam, rocket propellant, and other fields. HTPB is a commonly used binding polymer in industry to produce polyurethanes. HTPB synthesis via allylic radical propagation leads to varied compositions and conformations that govern this polymer's bulk physical and mechanical properties. The low surface energy and flexibility at low temperatures of HTPB-based polyurethane elastomers have been extensively studied [1-2].
