Study on the Correlation of Crosslink Network Structure and Tensile Properties of HTPB Binder

To study the crosslink network structure and the correlation with tensile mechanical properties of hydroxyl-terminated polybutadiene (HTPB) binder, tensile test and nuclear magnetic resonance test were introduced, the crosslink data and tensile stress-strain curves were obtained at various temperatures. The results show that the temperature has a significant effect on the crosslink density. When heating the samples from 30°C to 90°C, the crosslink density decreases and the transverse relaxation time increases. From 90°C to 130°C, the crosslink density raises at first and then becomes lower, and the transverse relaxation time keeps increasing. When the temperature rises from 30°C to 90°C, the elastic modulus and tensile strength of the binder are reduced, the elongation at break gets greater, and the tensile strength and the crosslink density has a linear relationship, which can predict the tensile strength of the binder at different crosslink densities.