A facile strategy for preparing of cross‐linkable natural fibers based on a Schiff base reaction

Abstract

The exploitation and utilization of natural fibers still face many challenges due to their high crystallinity and extensive hydrogen bond network. Therefore, sustainable and effective modification strategies are currently essential. In this work, we investigate the processing and mechanical performances of natural fibers modified by combining sodium periodate oxidation and subsequent Schiff base reaction. Steam‐exploded hemp fibers (HFs) were firstly oxidized with sodium periodate, and subsequently grafted with 1,10‐diaminodecane. A decrease in the glass transition temperature of oxidized‐aminated HFs (OAHFs) from 225 to 150°C was achieved as the dosage of periodate increased. Admirable mechanical properties were achieved despite a lower dosage of periodate due to melt bonding and chemical cross‐linking between the fibers during heat processing. Particularly, dynamic compression molding was applied to heat processes and effectively improved the melt bonding and the chemical crosslinking, which increased flexural strength from 58.2 to 69.9 MPa. This strategy was moderate and low cost. The resulted material has good processing performance and excellent mechanical properties, which have large industrial application prospects and potential in the field of biodegradable environment‐friendly materials.