Click Chemistry for Linker-Free BAMO-Based Energetic Sequence-Controlled Copolymers

In the field of energetic materials (EMs), soft chains are copolymerized with energetic polymers to improve flexibility. However, this often makes it difficult to achieve simultaneous optimization of the energy level and flexibility due to the random sequence. In this study, a simple approach is presented to develop energetic sequence-controlled polymers (ESCPs), alternate copolymers poly-(3,3-bis-(azidomethyl)-oxetane-glycol) (P-(BAMO-alt-EG)) and poly-(3,3-bis-(azidomethyl)-oxetane-tetrahydrofuran) (P-(BAMO-alt-THF)), through click reactions. This approach provides the potential to design and control mechanical and thermal properties in propellant binders by introducing various segments and regulating the sequence structure. These polymers display excellent thermal stability and demonstrate that regulated shorter segmental length promoted better flexibility and less residual carbon content without compromising the energy level of the propellant. The obtained kinetic parameters prove that P-(BAMO-alt-EG) released higher heat and accelerated the thermolysis process compared to P-(BAMO-alt-THF). These results demonstrate the potential of highly alternating ESCPs as a potential energetic propellant binder.