Optimized integration of Opuntia ficus-indica fibers for improved performance in plaster-based composites

The use of biomass is an important environmental step in the face of environmental conservation efforts and the ongoing depletion of fossil resources. From this perspective, cactus fibers are used in the manufacture of composite materials as a bio-reinforcement. In this paper, the influence of treatment with sodium hydroxide and paraffin oil on the properties of Opuntia ficus-indica fibers is studied. Then, the influence of the different treatments, using sodium hydroxide (NaOH), paraffin oil, or both combined, on the morphological characteristics of the outer surface of the fibers is studied. X-ray diffraction was performed on the natural and chemically treated fibers, which showed a higher crystallinity index for the treated cactus than for the natural cactus. FTIR spectroscopy was highly reliable along with the results of XRD and SEM analyses. In the study of the plaster-based composite reinforced with Opuntia ficus-indica, the addition of 3.75% of cactus fiber to plaster molasses resulted in an improvement of the mechanical and physical properties, with a 40% increase in flexural strength. When the double treatment was applied to the fibers, an increase in flexural strength of 53% was observed. There was also a high reduction in the density of the composite.