The properties of untreated sugar cane bagasse (SCB) and soft wood (SW) and their respective celluloses were investigated. The celluloses indicated improved crystallinity index values and decreased concentration of lignin and hemicellulose compared to their untreated counterparts. Three degradation models, Kissinger-Akahira-Sunose (KAS), Flynn-Wall-Ozawa (OFW), and Kissinger (KGR) methods were employed to determine apparent activation energy values. Generally, the thermal degradation processes of both sugarcane bagasse and soft wood included dehydration, degradation of hemicellulose and cellulose, whereas the lignin degraded from the degradation temperature of hemicellulose to the end of the cellulose. The apparent activation energy values obtained from the OFW and KAS models vary with the degree of conversion, and showed similar trends. The activation energies obtained by KGR were relatively lower than those obtained from the KAS and OFW methods.

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"The potential utilization of cellulose nanocrystals (CNCs) as reinforcing materials has lately attracted significant research attention. This is mainly due to their versatility and suitability for various applications in fields such as food packaging, cosmetics, biomaterials and pharmaceuticals. Several methods have been reported in the literature for isolating CNCs from plant sources, including acid hydrolysis, mechanical treatment and enzymatic hydrolysis, resulting in CNCs with different dimensions, crystallinities and thermal stabilities. However, acid hydrolysis using sulphuric acid (H2SO4) remains the favourite, as it requires shorter time and produces a stable suspension, with high crystallinity, compared to other methods. Sulphuric acid hydrolysis is generally performed with 64% acid concentration, with varying acid to fibre ratios, at temperatures around 45-50 °C, for 30-75 min duration under vigorous stirring. It typically produces needle-like structures, with the diameter and length in the range of 4–25 nm and 100–300 nm, respectively. This review analyses the results reported in the literature regarding the influence of hydrolysis parameters on the extraction of CNCs from various cellulosic materials. The study examines various hydrolysis parameters, specifically extraction time, temperature and acid concentration, to isolate CNCs with controlled morphology, crystallinity and thermal stability."

In this study, composite materials from agricultural biomass and polypropylene (PP) thermoplastic were produced by melt compounding using a melt mixer. The chemical interaction of sugarcane bagasse (SCB)-PP and soft wood (SW)-PP composites and corresponding cellulose were verified by Fourier-transform infrared spectroscopy (FTIR) analysis, X-ray diffraction (XRD) and Scanning electron microscopy (SEM). The cellulose composites were more crystalline than PP, trailed by PP/SCB and PP/SW composites. It was found that among composite materials, PP/SCB were least thermally stable compared to PP/ SW. The addition of extracted cellulose decreased the thermal stability of PP/SCB composites at higher filler content due to poor interfacial bonding as compared to PP/SW composites. SEM results confirmed a rough morphology and the presence of many voids resulting from fibre pull-out in composites, especially for the ones with higher fibre content. Dynamic mechanical analysis (DMA) of both PP/SCB and PP/SW composites indicated improvement in the storage modulus compared with neat PP.