WOOD RESEARCH Volume 68, Number 1, 2023
Nduduzo Khumalo, Masulubanye S. Mohomane, Linda Z. Linganiso, Cebisa E. Linganiso, Sandile Songca, and Motaung E. Tshwafo

Effect of acid hydrolyses on properties of cellulose/poly furfural alcohol (PFA) composites from maize stalk

The study investigated morphology and thermal properties of cellulose/poly furfural alcohol (PFA) composites prepared from maize stalk through acid mixtures. The cellulose nanocrystals (CNCs) were extracted from maize stalk via acid hydrolysis using mixtures of various acids. The prepared CNCs were encapsulated in a PFA matrix via in situ polymerization process using p-toluene sulfonic acid as catalyst. The properties of untreated maize stalk, cellulose and their nanocomposites were analysed by scanning electron microscope (SEM), X-ray diffraction (XRD), Fourier transmission infrared (FTIR) and thermogravimetric analysis (TGA). The crystallinity of maize stalk was generally increased after an acid hydrolysis dominated by H2SO4/HNO3 and H2SO4/HCl. The same trend was observed from TGA, except that H2SO4/H3PO4 and H2SO4/HClO4 dominated thermal stability trailed by H2SO4 hydrolysed CNC nanocomposite. The surface breakage of fibers observed in SEM images was depended on the strength of acids used to hydrolysed the CNC. There was also evidence of aggregation and cracked PFA surface with addition of acid hydrolysed CNCs, dependent on the acids strength. The H2SO4/HClO4 hydrolysed CNC/PFA displayed a fairly good dispersion of CNCs in the PFA matrix with no surface breakage.

WOOD RESEARCH Volume 62, Number 6, 2017
Samson M. Mohomane, Linda Z. Linganiso, Thuli Buthelezi, and Tshwafo E. Motaung

Effect of extraction period on properties of sugarcane bagasse and softwood chips cellulose

This work evaluates the extraction of sugarcane bagasse (SCB) and soft wood (SW) celluloses with alkali treatment followed by bleaching process using sodium chlorite at different time. The influence of extraction time (2 hrs and 4 hrs) on the thermal, crystallinity and morphological properties was investigated. The extracted celluloses were analysed by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transmission infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). The aromatic skeletal vibrations of lignin and hemicellulose confirmed the extraction of cellulose which varied extraction time. TGA analysis shows that the untreated SCB degrade earlier than their respective celluloses and the prolonged treatment affects the onset of main degradation. XRD results showed that extracted celluloses had greater crystallinity index, and was affected at prolonged time due to long range destruction of cellulose crystals. The SW revealed a complex behaviour due to the dominated lignin content as revealed from chemical composition analyses.

WOOD RESEARCH Volume 64, Number 6, 2019
Silungile H. Ngceza, Linda Z. Linganiso, Setumo V. Motloung, Lehlohonolo F. Koao, Ella C. Linganiso, and Tshwafo E. Motaung

The effect of silver salts on the properties of sugarcane bagasse cellulose

In this study, X-ray diffraction (XRD), thermogravimetric analysis (TGA), and Fouriertransform infrared spectroscopy (FT-IR) methods were used to study the structure and the thermal degradation of the cellulose modified with silver nitrate, silver sulphate and silver borate. The absorption of the nitrate derivative is more intense followed by the borate. All the cellulose derivatives showed two degradation steps, except for bromate derivatives which indicated the third peak that is related to a nature and chemistry of a derivative presence. The modification seems competent for an application for modified fillers in polymer composites.

WOOD RESEARCH Volume 64, Number 4, 2019
Thulani Shabangu, Linda Z. Linganiso, Tshwafo E. Motaung, Motloung V. Setumo, and Lehlohonolo F. Koao

Comparison of fibre from maize stalk domains and sugar cane bagasse

The aim of this study is to investigate properties of pulverised cellulosic material from parts of maize stalks and sugar cane bagasse (SCB). Both materials were foremost subjected to a cutting mill before boiling with water. The chemical compositions and mechanical properties of the maize stalk residues and sugar cane bagasse were performed using a TAPPI standard. Optical microscope, Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA) and Ultraviolet-visible spectroscopy (UV-Vis) were used to characterise the materials. Rind displays thinner and longer fibres, which are less unequal and almost quadrangular. In fact, it has a highest crystallinity trailed by nodes and sugar cane bagasse in sequence. Interestingly, thermal stability of SCB is dominating followed by rind and nodes.

WOOD RESEARCH Volume 64, Number 2, 2019
Linda Z. Linganiso, Thuli Buthelezi, and Tshwafo E. Motaung

A comparative study of sugarcane bagasse and soft wood

This article investigated properties of different lignocellulosic biomasses. Both acidified and non-acidified sodium chlorite were used to treat wood chips and sugar cane bagasse. Images were part of characterizations that included X-ray diffraction (XRD), thermogravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FT-IR). Interestingly the results indicated that biomasses followed the similar crystallinity trend while thermal stability and functional groups on the cellulose surface seemed to differ. All the FT-IR spectra showed 8 main peaks but spectra of bagasse have an additional peak. Stretching vibrations of the O-Hand the C-H stretching group in cellulose molecules were clear for all biomasses. The treatment clearly removed most of aromatic compounds normally attributed to lignin and hemicellulose.