Application of cellulose nanofibrils in polyvinyl alcohol composite films

Fenton cellulose nanofibrils (F-CNF) were prepared by Fenton oxidation with the followed homogenization and then F-CNF /PVA composite films with the F-CNF additives from 1% to 20% were prepared by solution casting method. Scanning electron microscopy (SEM), confocal laser scanning microscope (CLSM), Fourier transform infrared spectroscopy (FTIR), universal tensile testing machine, swelling property detection, thermogravimetric analysis and soil burial degradation rate test were used to characterize the microstructure, chemical structure, mechanical properties, hygroscopicity, thermal stability and biodegradability of the composites. The results showed that a large number of hydrogen bonds were formed between F-CNF and PVA molecules and an acetal reaction occurred. F-CNF can be uniformly dispersed in PVA matrix, and both have good interfacial compatibility. After the addition of F-CNF, the tensile strength and elastic modulus of the composite films were significantly improved, the water absorption of the composite material was reduced, and its thermal stability was improved. When the amount of F-CNF was 15%, the tensile strength and Young’s modulus of the composite films were 65.27 MPa and 1460.32 MPa, respectively, which were 217.77% and 830.69% higher than those of pure PVA.