A Standardization Approach to Cellulose Nanomaterials for Industrial Deployment

A coherent standardization framework is essential for the industrial deployment of cellulose nanomaterials (CNMs). Although CNMs offer attractive properties for diverse industrial applications, their distinct morphological types—cellulose nanocrystals (CNCs), individualized cellulose nanofibrils (iCNFs), and entangled cellulose nanofibrils (eCNFs)—introduce morphological complexity that hinders reproducible quality evaluation. ISO has established terminology and several test method standards; however, testing standards remain limited for CNCs and iCNFs, and are still lacking for eCNFs, leaving a significant gap between material characterization and industrial use. This study proposes a structured framework that aligns terminology, test method, testing, and specification standards along the CNM industrialization pathway. The framework highlights the essential role of testing standards as the appropriate evaluation basis for CNMs at their present developmental stage, in contrast to specification standards suited to mature materials with clearly defined applications. A complementary scenario-based methodology is also introduced to support coherent and reproducible development of individual testing standards. By positioning existing ISO CNM standards within this pathway and clarifying the evaluative and bridging functions of testing standards, this study provides an industry-oriented foundation for reliable CNM quality assessment. The conceptual approach may also support standardization strategies for other bio-based materials in similarly early stages of industrialization.