Interstitial solid solution formation in nitrocellulose: providing a route for low- temperature processing and material design

This work investigates the structural transformations and mechanical properties of nitrocellulose (NC, cellulose nitrate) modified with an azido plasticizer. Contrary to the traditional paradigm assuming amorphization, our wide-angle X-ray diffraction (WAXD) data reveal that its phase state is best described as an interstitial solid solution. The retention of chain orientation within the NC crystalline domains enabled low-temperature (~ 60°C) aqueous processing. This approach allows for the fabrication of monolithic materials, in particular films and membranes, with enhanced strength characteristics and pronounced structural anisotropy. The presented approach provides a basis for the energy-efficient and safe production of high-strength anisotropic materials based on nitrocellulose.