The influences of plasticizer B2 mass fraction on the performances of CAB/B2 polymer composite materials: Combining experiments and simulations

Cellulose acetate butyrate (CAB)/B2 (50 wt% bis(2,2-dinitropropyl)-acetal and 50 wt% bis(2,2-dinitropropyl)-formal) polymer composite material is a commonly used binder system to prepare polymer bonded explosives (PBXs). However, few literature report the influence of plasticizer B2 mass fraction on the performance of CAB/B2 polymer composite binder systems. In this study, experiment measurements and computer simulations are utilized to explore the influences of B2 mass fraction on the glass transition temperature, mechanical property, and thermal decomposition of CAB/B2 polymer composite materials. The results show that, with an increase in B2 content, the glass transition temperature and fragility of CAB/B2 are decreased, and the plasticity and ductility of CAB/B2 are enhanced. Moreover, the thermal decomposition mechanism, decomposition products, and decomposition path of CAB/B2 are unchanged with the increase in B2 content. Besides, the researchers also demonstrate that the addition of B2 is positive to the formability of CAB/B2 systems and is negative to the thermal stability of CAB/B2 systems, whereas the content of B2 has little influences on the thermal stability of CAB/B2 systems. The results obtained from this work can provide some guidance for the designs of high-energy density PBXs.