Effects of HTPB with Different Molecular Weight on Mechanical Properties of HTPB/TDI System

Abstract

t is found that the molecular weight of Hydroxy-terminated polybutadiene (HTPB) influences curing behaviors of HTPB/2,4-toluene diisocyanate (TDI) system and the mechanical properties of PBXs. Effects of the molecular weight of HTPB on the viscose viscosity,the cure time, and mechanical properties of polymer were studied by brookfield viscometer, hardness tester and tension test with the molecular weight of HTPB varying from 1500~4000.The experimental results show that the viscose viscosity increases slowly and the cure time is extended obviously,tensile strength decreases and elongation at break increases when the molecular weight of HTPB increases. Dynamic mechanical studies show that glass transition temperature and dynamic storage modulus decrease with the molecular weight of HTPB increasing.