Characterization of Paper Mulberry Bast Fiber and Cotton Linter Fiber for Nanocellulose Production

Abstract

This study investigates the suitability of non-woody fibers such as paper mulberry bast fiber (PMBF) and cotton linter mixed pulp (CLMP) as raw materials for the production of nanocellulose. PMBF, CLMP, and hardwood bleached kraft pulp (HwBKP) were used as a control, and their chemical compositions, fiber characteristics, initial freeness, crystallinity, and shape were measured. Based on these findings, an efficient method for producing various types of nanocelluloses using PMBF and CLMP was explored.BRThe chemical compositions revealed that PMBF and CLMP had higher alpha cellulose content than HwBKP, which indicates the functionality of using two non-woody fibers in the production of nanocellulose. The longest PMBF had higher initial freeness and crystallinity than CLMP and HwBKP, which indicates that a high cost for chemical or mechanical pretreatment is required to produce cellulose nanofibril (CNF) using PMBF. Additionally, the CLMP had the lowest crystallinity of the three materials due to its relatively high content of hemicellulose and lignin, as revealed in the chemical composition analysis, and it had lower initial freeness than HwBKP, which indicates that the CLMP can be easily fibrillated through mechanical treatment compared to a PMBF.BRThus, using PMBF as a raw material for cellulose nanocrystal (CNC) produced by acid hydrolysis and CLMP as a raw material for CNF produced by mechanical treatments was efficient.