Preparation and application of nanocellulose from Miscanthus × giganteus to improve the quality of paper for bags

Abstract

We present the study of the preparation of pulp and nanocellulose from Miscanthus × giganteus to improve the quality of the paper for bags. The organosolv miscanthus pulp (OMP) was prepared by the environmentally friendly organosolv method—cooking in a solution of peracetic acid at the first stage and the alkaline treatment at the second stage. Nanocellulose was obtained by hydrolysis of never-dried OMP and subsequent ultrasonic treatment. Structural changes and crystallinity index of OMP and nanocellulose were studied by SEM and FTIR methods. X-ray diffraction analysis confirmed an increase in the crystallinity of OMP and nanocellulose as a result of thermochemical treatment. The nanocellulose had a density of up to 1.6 g/cm3, transparency up to 82%, a crystallinity index of 76.5%, and tensile strength up to 195 MPa. The AFM showed that the particles of nanocellulose have a diameter in the range from 10 to 20 nm. A TGA analysis confirmed that nanocellulose films have a denser structure and lower mass loss in the temperature range 320–440 °C compared to OMP. We established the positive effect of nanocellulose application on the physical and mechanical properties of paper for bags. The application of nanocellulose allows replacing synthetic reinforcing materials and more expensive sulfate unbleached pulp with waste paper in the production of paper and cardboard.