Cellulose of sisal fibers integration in papermaking: mechanical and thermal characterization

Over the past few years, natural fibers have attracted the attention of various researchers due to their different properties like their durability and biodegradability as well as their large range of applications in several sectors. Sisal fibers, in particular, derived from the Agave sisalana plant, are characterized by their mechanical strength and versatility, making them particularly suitable for producing paper and composite materials. This study presents an in-depth investigation of the mechanical and thermal properties of natural sisal fibers and cellulose extracted from these fibers for papermaking applications. The main results show that sisal fibers exhibit impressive tensile strengths ranging from 80 to 220 MPa and Young’s modulus of 125 GPa. In contrast, the extracted cellulose exhibits a tensile strength of 40–75 MPa and an exceptional Young’s modulus of 530 GPa, indicating superior stiffness. The crystallinity index was measured to be 60.0% for sisal fibers and 64.5% for cellulose, indicating a better structural organization of the extracted cellulose. In addition, thermogravimetric analysis indicates improved thermal stability for cellulose, with a mass loss of only 31.5% at 615 °C compared to 45% at 605 °C for natural fibers. Finally, paper made from extracted cellulose exhibits remarkable mechanical properties, with a tensile strength of 1665 kN/m and a Young’s modulus of 4504 GPa. These results highlight the considerable potential of cellulose from sisal fibers for producing high-performance papers and open up promising avenues for improving the stability and mechanical performance of the final products.