Problem definition and objectives: The use of modern technologies, such as the application of nanoparticles in improving the quality of durable paper production, has opened up a new horizon. This study investigates and compares durable papers made from cotton and bottom combers pulp with a combination of nanocellulose fibers and lignocellulosic nanofibers. The main objective of this research is to evaluate the impact of nanofibers on the physical and mechanical properties of the papers made from cotton and bottom combers pulp, as well as to identify the potential for enhancing their quality and performance.
Methodology: In this study, refined paper pulp of cotton fibers, bottom combers fibers, cellulose nanofibers, lignocellulosic nanofibers was obtained from a durable paper factory and then 60 gm-2 grams handsheets paper was made. Finally, the morphology of the fibers and the physical and mechanical properties of the manufactured papers were evaluated.
Results: The obtained results showed that the tensile strength index of the paper prepared from the combination of 5% cellulose nanofibers and 1% starch was about 83% higher than the paper prepared from 100% bottom combers pulp. Burst strength index of in the combination of 5% cellulose nanofibers and 1% starch was 75% higher than the combination of 100% bottom combers pulp. Tear strength index of the paper prepared from the combination of 5% cellulose nanofibers and 1.0% polyacrylamide was 17% higher than the combination of 5% cellulose nanofibers and 0.1% polyacrylamide pulp. The surface smoothness of the paper prepared from the combination of 5% lignocellulosic nanofibers and 0.1% polyacrylamide of the bottom combers pulp was about 28% higher than the combination of 5% lignocellulosic nanofibers and 1% starch. The porosity of the paper prepared from the combination of 100% paper pulp obtained from bottom combers cotton fibers was about 433% higher than the combination of 5% lignocellulosic nanofibers and 1% starch. The opacity of the paper prepared from the combination of 5% of lignocellulosic nano fibers and 0.1% of polyacrylamide was 6% higher than the combination of 100% paper pulp obtained from cotton fibers. The brightness of the paper prepared from the combination of 5% cellulose nanofibers and 1% starch was 18% higher than the combination of 5% lignocellulosic nanofibers and 1% starch.
Conclusion: This study showed that the combination of nanofibers with cotton and bottom combers pulps can significantly improve the physical and mechanical properties of durable papers. The results indicate that the tensile strength and burst resistance in papers containing cellulose nanofibers were notably higher than those made solely from bottom combers pulp. Additionally, the tear resistance improved with the use of a combination of cellulose nanofibers and polyacrylamide, demonstrating the effectiveness of this mixture in enhancing paper strength. On the other hand, the surface smoothness and opacity of papers containing lignocellulosic nanofibers were improved compared to other combinations, which could enhance the aesthetic quality and printability of the paper. The porosity of papers produced from bottom combers pulps was significantly higher than that of the nanofiber combinations, potentially affecting ink absorption and other functional characteristics. Furthermore, the brightness of the papers increased with the use of cellulose nanofibers, which could impact specific applications such as printing and packaging. Overall, this research emphasizes that integrating nanofibers in paper production can lead to the creation of higher quality and more durable papers. In general, this research emphasizes that the durable paper made from underfelt possesses suitable characteristics, and its use as a complete or significant portion of the pulp needed for the production of various types of durable papers is recommended.