Natural fibers could serve as viable and abundant alternatives to the expensive and non -renewable synthetic fibers as reinforcement in thermoplastic composites. The potentiality of banana stalk fiber at reinforcing a low density polyethylene matrix was examined in this study. Fibers were extracted from the stalk of banana plant and characterized for its chemical composition and fiber contents. The fibers were modified by pulping with caustic soda to increase it wettability. The fiber dimension was measured using a binocular light microscope. FTIR spectra was used to identify the functional groups of modified and unmodified fibers. The composites were produced using a single -screw extruder, pelletized and then processed into test specimen samples by injection molding. The fiber volume in the polymer matrix was varied from 5.4 to 20 %. The effects of chemical treatment and increasing fiber content on the moisture absorption and mechanical properties of the composites were examined. The results showed that fiber of banana plant were characterized by medium to long fiber length (2.84 mm). The lignin content (7.99 %) was relatively low indicating a lower value of chemical consumption in the modification step. The SEM micrograph of the composite cross section showed good fiber/matrix interfacial bonding. The water absorption capacity of the composites increased with increase in fiber loading while the treated fibers showed a reduction in hydrophylicity of the composites. The treated fibers showed improved tensile strength and can thus be utilized in the production of composites with better properties

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Binderless fiberboards were made from oil palm (Elaeis guineensis) empty fruit bunches with two treatments: steam explosion and Fenton reagent oxidation. Fiberboards were prepared with a targeted density of 1.20 g/cm 3 and a thickness of 4 mm. A factorial experimental design 2 2 with two center repetitions and one repetition was applied for each treatment. The oil palm waste was oxidized with Fenton reagent using a H 2 O 2 /Fe 2+ ratio of 2%/0.2% to 4%/0.4% and a pressing temperature of 170 to 190 °C. Steam explosion was carried out at a severity factor of 3.5 to 4.0 at the same pressing temperature. Both treatments were examined under two major response variables: mechanical properties (modulus of rupture, MOR, and modulus of elasticity, MOE) and physical properties (thickness swelling, TS, and water absorption, WA). Steamexploded samples developed better physico-mechanical properties than those that underwent Fenton reagent oxidation. The best results were obtained from fiberboards treated with the highest steam explosion design conditions (severity 4 and pressing temperature 190 °C) to give optimum values of MOE 3100.09 MPa, MOR 28.49 MPa, TS 11.80%, and WA 22.74%. Binderless fiberboards made from steam explosiontreated pulp satisfied favorably well the Colombian Standard NTC 2261.

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Plants have very high potential as alternative source of bio-reducing and capping agents in nanoparticles (NPs) synthesis. Silver nanoparticles (AgNPs) were synthesized from Tetrapleura tetraptera leaf extract. The UV-vis spectrophotometer was used to observe the formation of the NPs at various time intervals and ratios of leaf extract to AgNO3 solution. The properties of the AgNPs synthesized were characterized by FTIR and Scanning Electron Microscope (SEM) equipped with Energy Dispersive X-ray Spectroscopy (EDX). Antimicrobial activities of the AgNPs synthesized were evaluated against ten human pathogens using agar well diffusion method. The rate of formation of the AgNPs was shown to increase with respect to time and ratio of leaf extract to AgNO3 solution. The EDX result showed signal energy peak for silver atom at 3.0-3.8 KeV. The AgNPs was characterized with FTIR peaks around 3280, 1620, 1400 and 1040 cm−1 assigned to O-H, C=O, C–O–H and C-C groups respectively, as possible stabilizing and capping groups. The AgNPs showed maximum inhibitory activity against Staphylococcus aureus, Escherichia coli and Salmonella sp.