Synthesis and Properties of HTPB/PTMG Polyurethane Elastomers

Polyurethane (PU) elastomers were prepared using hydroxy-terminated polybutadine (HTPB), polytetramethylene (PTMG), 4,4'-diphenylmethane diisocyanate, and 1,4-dihydroxybu-tane. The effects of HTPB/PTMG mass ratio and preparation methods on the mechanical properties of PUs were studied. The results showed that the tensile and tear strengths decreased with increasing HTPB/PTMG mass ratio. With the increasing of the mass ratio of HTPB/PTMG, the loss of mechanical properties of PU elastomers prepared by prepolymer method is less than that by the improved one-step method,and that of the latter is less than that by the one-step method. Dynamical mechanical properties analysis (DMA) revealed that the heat generation also decreased with increasing HTPB/PTMG mass ratio, and the microphase separation weakened.