In this work, the adhesion behavior of chemically treated banana and coir Colombian fibers embedded in polylactic acid (PLA) and unsaturated polyester resin (UPR) matrices was investigated. Both types of fibers were treated with a 5 wt.% sodium hydroxide solution for one hour. The properties of treated and untreated fibers were determined by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and tensile tests. To evaluate the adhesion behavior of the fibers in PLA and UPR matrices, pull-out tests were performed, and the percentage of broken fibers was determined. The results showed that alkaline treatment improved the fibers’ physicochemical, mechanical, and thermal properties. In addition, the alkaline treatment was able to improve the adhesion behavior of coir and banana fibers to PLA and UPR matrices. The banana fibers showed a percentage of broken fibers of 100%, while the coir fibers showed a slight increase in IFSS value. This behavior is attributed to the improvement in surface roughness due to the removal of non-cellulosic composites and impurities.

This study investigated the impact of drying temperature on the physicochemical and mechanical properties of banana pseudostem fibers sourced from the Cordoba region in Colombia. Banana fibers (BFs) were extracted through mechanical decortication from the banana pseudostem (BP) of the plant and subsequently oven-dried at temperatures of 40 °C and 90 °C. Six mathematical models were employed to analyze the drying behavior of the fibers. The density of the BFs was determined using the apparent density method, and their chemical composition was evaluated via bromatological analysis. Fiber diameter was measured using optical microscopy (OM). The BF samples were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TG), contact angle measurements, and tensile testing. The results indicated that noncellulosic materials were removed from the fibers when dried at 90 °C, as evidenced by alterations in thermal degradation and fiber surface morphology observed through TG and SEM, suggesting a reduction in lignin content. While drying temperature did not affect fiber stiffness or ductility, a correlation with fiber diameter was noted. Thinner fibers, ranging from 148 to 250 μm, exhibited increased tensile strength and Young’s modulus, attributed to a more compact microfibril arrangement.

In the present study, the influence of drying temperature, mercerization, and epoxy coating on the physicochemical and mechanical properties of Colombian CFs and their interfacial adhesion with a PLA matrix were studied. CFs were extracted from the mesocarp of Cocos nucifera husks by retting. The fibers were oven-dried at two drying temperatures, 40 °C and 90 °C. These samples were then mercerized and coated with epoxy resin. Pullout tests were performed to assess the bonding between the fibers and the PLA matrix. The results revealed that drying at 90 °C significantly enhanced fiber stiffness, yielding a Young’s modulus of 1.99 ± 0.48 GPa. Scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) revealed that the mercerization treatment partially removed lignin from the surface of the fibers, increasing their roughness and facilitating mechanical interlocking. The subsequent epoxy resin coating introduced functional groups that can enhance the wettability of PLA. Compared with the untreated fibers, the combination of the mercerized and polymeric coatings resulted in a 62% increase in the Young’s modulus (3.57 ± 0.95 GPa) and a 43% increase in the tensile strength (108.43 ± 35.72 MPa). Additionally, single-fiber pull-out tests revealed that mercerized and coated fibers (CM-PLA) had double the interfacial shear strength (0.916 MPa) of untreated fibers, demonstrating improved fiber‒matrix adhesion.

In this work the microstructure, texture and mechanical properties during different stages of reverse cold rolling (RCR) process on aluminium alloy AA1100-H14 were analysed. Microstructure was observed using optical and electron scanning microscopy. Texture was analysed using X-ray diffraction (macrotexture) and electron back-scattering diffraction (microtexture) techniques. Tensile test and microhardness measurements were carried out. Results showed that a high deformation using RCR was obtained in samples of annealed state leading to maximum values of tensile strength and hardness, along with a reduction of ductility. Intensity of -fibres decreased producing unstable textures {112} while microstructure exhibited refinement of grain, with enlarged morphology.

This study explores the use of banana pseudostem fibers from Córdoba, Colombia, as reinforcement in polymer composites manufactured through vacuum-assisted resin transfer molding (VARTM). The fibers were decorticated, oven-dried at 40 °C, and subjected to mercerization and epoxy coating treatments. Plain-weave fabrics were produced using continuous yarns composed of 10 and 15 fibers, both treated and untreated. Experimental analyses included pull-out tests, thermogravimetric analysis, fourier-transform infrared spectroscopy, winding speed, surface twist angle, and tensile strength tests for yarns, as well as tensile load, adhesion, and permeability tests for fabrics and tensile and flexural strength tests for composites. Treated yarns exhibited a slight increase in diameter and a lower extraction (25%) compared to untreated yarns (33%). Although treated fabrics showed enhanced permeability and improved resin infiltration, untreated fabrics demonstrated superior mechanical performance, with a tensile load of 2.33 kN in comparison to 1.37 kN for treated yarns. The highest tensile strength of 76.56 MPa was achieved in composites reinforced with three layers of untreated fabric, while the best flexural strength of 86.93 MPa was observed in single-layer composites with the same configuration. These results emphasize the potential of untreated banana fiber fabrics as promising reinforcement in structural composite applications.