Environmental impact and sustainability of nanocellulose-based nitrated polymers in propellants.

Nanocellulose-based nitrated polymers derived from cellulose nanofibrils (CNFs), cellulose nanocrystals (CNCs), and bacterial nanocellulose (BNC), represent a significant innovation in the field of propellant materials. These renewable and biodegradable materials align with sustainability goals, offering reduced environmental impact compared to traditional synthetic propellants. This review highlights key findings on their environmental advantages, emphasizing greener synthesis methods, efficient production processes, and life cycle benefits. CNFs, CNCs, and BNC demonstrate competitive energetic properties while reducing reliance on non-renewable resources and minimizing harmful byproducts during production. Advances in enzymatic pretreatments, acid recovery systems, and renewable feedstocks have improved resource efficiency and scalability. Moreover, these nanocellulose-based nitrated polymers provide an opportunity to balance high-performance requirements with environmental priorities, addressing a critical challenge in modern propellant technology. Despite their promise, challenges such as performance optimization, regulatory compliance, and cost-effective scalability remain. This review calls for further research to develop safer nitration techniques, optimize production processes, and conduct comprehensive life cycle assessment (LCA). Collaborative efforts among researchers, industry, and policymakers are essential to overcome these barriers and establish nanocellulose-based nitrated polymers as sustainable alternatives for propellant applications.