Effect of hydrothermal pretreatment on solubility and formation of kenaf cellulose membrane and hydrogel

• Published in: Carbohydrate polymers 2015-01, Vol.115, p.62-68
• Main Authors: Gan, Sinyee, Zakaria, Sarani, Chia, Chin Hua, Padzil, Farah Nadia Mohammad, Ng, Peivun
• Format: Article
• Language: English
• Subjects: Alkaline aqueous solution; Autoclave; Rapid dissolution; Regenerated cellulose; Urea
• ISSN: 0144-8617; 1879-1344
• DOI: 10.1016/j.carbpol.2014.08.093

•Hydrothermal pretreatment kenaf was produced by using autoclave in hot oil bath.•As hydrothermal reaction time on kenaf increases, the molecular weight of kenaf decreases and its solubility increases.•Cellulose membrane and cellulose hydrogel were formed from hydrothermal pretreated kenaf. The hydrothermal pretreatment on kenaf core pulp (KCP) was carried out using an autoclave heated in a oil bath at 140°C for 0.5/1/3/5h. The hydrothermal pretreated kenaf (HPK) was dissolved in a LiOH/urea aqueous solution and subsequently used to produce cellulose membrane and hydrogel. The effects of hydrothermal pretreatment time on solubility, viscosity, crystallinity and morphology of the cellulose membrane and hydrogel were investigated. The hydrothermal pretreatment leads to higher cellulose solubility and higher viscosity of the cellulose solution. The formation of cellulose II and crystallinity index of the cellulose membrane and hydrogel were examined by X-ray diffraction (XRD). The pore size of the cellulose membrane and hydrogel displayed an upward trend with respect to the hydrothermal pretreatment period observed under a field emission scanning electron microscope (FESEM). This finding provides an efficient procedure to improve the solubility, viscosity and properties of regenerated cellulose products.