One of the big problems in Indonesia currently is waste management, especially plastic waste.Plastic that comes from food packaging is a source of environmental problems because it is difficult to decompose naturally.Therefore, it is necessary to look for alternative materials to replace petroleum-based plastic packaging, with other materials based on renewable and biodegradable materials.This study aims to determine the properties of cellulose films with the addition of glycerol and lemongrass oil based on the characterization of mechanical tests, water and vapor resistance tests, and functional groups using FTIR-ATR spectrophotometer and the possibility of their use as packaging.Cellulose film was fermented from coconut water and coated sequentially by glycerol (5,10,15 and 20 % w/w) and lemongrass oils.Coating method with lemongrass oil was done for 0, 1, 3, 5, 7, and 14 days.The cellulose film was characterized using tensile strength, water resistance test, water vapor test and FTIR-ATR.The results showed that glycerol and lemongrass oil can affect the physic and mechanic cellulose film.The cellulose film with a concentration of glycerol of 5% and coated by lemongrass oil for 5 days has the best elongation and modulus Young 230.39 MPa.The cellulose film with concentration of glycerol 5% and coated by lemongrass oil for 14 days has the best water vapor resistance and water resistance value of 88.298% and 49.93 respectively and shows an increase in function group intensity of C=O.Thus, the film of cellulose-glycerollemongrass is an alternative packaging material.
Metal matrix composites (MMC) are gaining relevance in many load-bearing applications due to their low density and high stiffness.Compared to traditional monolithic metals, MMC offers exceptional mechanical and tribological properties.Boron carbide is a preferred reinforcement material for MMC due to its lower density, higher hardness, strong refractoriness, and high elastic modulus than other ceramic reinforcements.This paper provides a comprehensive review of the processing, properties, and microstructure of B 4 C-reinforced MMCs, emphasizing the potential use of aluminum LM6 alloy as a matrix material.The incorporation of B 4 C in aluminum LM6 alloy offers improved strength and stiffness, reduced weight, and increased resistance to wear and fatigue.The review presents a detailed analysis of the properties of B 4 Creinforced aluminum LM6 MMCs, including tensile strength, hardness, wear resistance, and fatigue life, and the importance of the microstructure and interfacial bonding between the reinforcement and matrix.The paper explores current developments and opportunities for the use of B 4 Creinforced aluminum LM6 MMCs in various fatiguerelated applications, providing an insight into the future development and opportunities of this class of materials.Need for further research to optimize the processing and properties of these composites is featured.
The increasing use of metal oxide materials has met with equal concern as regards associated health risks and environmental transference.NMC-family (LiNi x Co y Mn z O 2 , where x+y+z=1) energy storage materials are complex transition metal oxides that are being rapidly deployed as replacements to the conventional lithium-ion batteries (LiBs) in the electric vehicle industry.Sustainable catalysis is another area of increasing study since multi-component oxides have a high propensity for cleaving strong chemicals such as the carbon-fluorine bond.NMC materials are mostly synthesized through different thermomechanical processes, with the final composition depending on the required properties in the derived nanostructures.The biological impact of NMC-type materials has been found to be dependent not just on the overall mass, but also on the mass distribution which could be in the form of micro or nanostructures.This study therefore assesses the toxicity effect of NMC-family nanoscale material for energy storage and catalysis, with a view to determining possible safety levels as regards the composition of constituent materials.Preliminary toxicity studies were conducted on inoculated S. oneidensis, B. subtilis and D. magna substrates exposed to NMC materials for time intervals ranging from 0 to 72h and found a direct relationship between the ease of release of Ni and Co ions and cellular respiration and growth.The chemical transformation of NMC nanomaterials was however found to favor an ion release of the order Li > Ni > Co > Mn, although this is an entirely slow process.Altering the configuration of NMC materials through Mn enrichment was also found to significantly reduce its dissolution and could be an important approach to preventing its release into the environment.
Comprised of biopolymer matrix and/or bio-fiber reinforcement, bio-composites are environmentally friendly, lightweight, sustainable, and normally biodegradable.Their unique characteristics have enabled them an alternative material for replacing conventional metallic materials and other composites such as glass fiber reinforced composites.This work is focused on developing and characterizing a novel bio-composite that combines a natural fiber reinforcement with a unique α-resorcylic acid-based epoxy bio-resin.Kenaf fiber mats are impregnated with the epoxy bio-resin and compression molded into a bio-composite.Thermal properties of the bio-composite are characterized with differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA) and thermogravimetric analysis (TGA).Indentation testing in a micro-scale is conducted on the bio-resin matrix and the fiber cross sections.The elastic modulus of the fiber transverse cross section is found to be 7.8 GPa, higher than that of the bio-epoxy resin, 4.3 GPa.Furthermore, the tension performance of the bio-composite is evaluated and compared with that of a conventional epoxy composite with similar kenaf fiber percentage.The bio-epoxy composite has comparable tensile modulus and strength with the conventional epoxy composite.Finally, the fracture surface of the tested samples is characterized using scanning electron microscopy (SEM) and different failure modes, such as fiber fracture, fiber pullout, fiber defibrillation, and matrix fracture, are observed.It is concluded that this novel bio-composite has a great potential to replace conventional epoxy resin based composite for semi-structural applications.
