Cellulose nanofiber reinforced starch film with rapid disintegration in marine environments
Raghav Soni, Yu‐I Hsu, Taka‐Aki Asoh, Hiroshi Uyama
Abstract
Abstract Floating plastic debris in the ocean creates major environmental problems and threatens marine life. Conventional marine‐degradable plastics can remain in seawater for many years due to their strength and stability. In this study, we prepared a cellulose nanofiber‐reinforced starch film that rapidly degrades in marine environments. (2,2,6,6‐Tetramethylpiperidin‐1‐yl)oxyl (TEMPO) mediated oxidation was performed to prepare highly fibrillated TEMPO‐oxidized cellulose nanofiber (TCNF). The TCNF was blended with cationic starch (CS) to develop a TCNF/CS film, which exhibited adequate mechanical strength (~50 MPa) and freshwater durability. In contrast, the neat TCNF and CS films collapsed in freshwater. Results showed that the TCNF/CS film disintegrated and lost its strength and stability in seawater. The wet strength of the TCNF/CS film decreased to ~50 kPa after 28 days of seawater immersion, while that of the neat TCNF film was steady at a wet strength of ~25 MPa due to ionic crosslinking. Owing to its rapid disintegration ability in marine environments, the TCNF/CS film is a potential next‐generation packaging material that can help address the problem of floating debris.