Recyclable cellulose nanofibers reinforced poly (vinyl alcohol) films with high mechanical strength and water resistance.

ABSTRACT

Sargasso cellulose nanofibers (CNFs) and polyvinyl alcohol (PVA) components were composed to generate novel KCNF/PVA films by a simple and benign crosslinking strategy. Sargasso CNFs are a potential reinforcement material due to its extremely long length (15-20 µm) and natural nanostructure. The low water resistance of PVA limits their use in humid and watery environments. However, the chemical cross-linking between sargasso CNFs and PVA consumes a large number of hydrophilic hydroxyl groups, the resulting KCNF/PVA films exhibited outstanding water resistance (water contact angle 119°). Especially, the wet strength of KCNF/PVA films (50 MPa) was raised by 92 times when compared to that of pristine PVA films (0.54 MPa). Furthermore, these KCNF/PVA films could be dissolved and recycled easily. The regenerated films also show outstanding mechanical performance.