Hardiansyah Tambunan

This study aims to evaluate the properties of poly(propylene) or PP composite reinforced with coconut coir fibers, and how these vary with fiber length and composition ratio. This innovative thermoplastic composite material was manufactured using a low-tech process from only PP, coconut coir fibers, and xylene (dissolution agent). Therefore, this process is widely accessible whilst both reusing/recycling waste plastic and making use of waste fiber material to produce a useful material that can fulfill demand for wood products, which has many environmental benefits. In this research, the coconut coir fibers are used as reinforcement, as well as the filler of the composite. Nine variations in composite material were produced from three length categories of fibers (2–5 mm, 10–20 mm, and 30–40 mm) and three composition ratios (60:40, 70:30, and 80:20) of predominant plastics of PP and fibers. Physical properties of the respective composite, such as density, moisture content, and thickness swelling, were fulfilled to the Japanese Industrial Standard (JIS) for particleboard. Mechanical properties of the composites showed that both modulus of elasticity (MoE) and modulus of rupture (MoR) decreased as the length of the fibers used increased. Conversely, an increase in the proportion of PP resulted in a stronger composite. However, statistically, the interaction between the amount of PP and the length of coir fibers within the biocomposite did not influence their quality. These results demonstrate that a low-cost process for manufacturing composite from waste materials can meet most industry standards and indicate that further refinement of the process, building on these findings, could achieve an innovative thermoplastic composite with widespread structural applications whilst delivering environmental benefits.

The development and utilization of wood briquettes is one of the efforts to reduce dependence on fossil fuels, including to fulfill overseas market need. This study aimed to evaluate the properties of wood briquettes made of the branches of three mangrove species and to analyze the effect of different wood species of mangrove branches, and the types of starch adhesive, on the quality of wood briquettes. The wood briquettes made in this study were 3 cm × 4 cm in a cylindrical shape using three wood species of mangrove branches, namely mata buaya (Bruguiera sexangula), buta-buta (Excoecaria agallocha), and bakau minyak (Rhizophora apiculata), while the adhesives used were tapioca starch, maize starch, and potato starch. The results showed that the moisture, ash content, and calorific value of the wood briquettes mostly met the ISO 17225-3:2-2020 class A2 standard and the specification and quality standards of wood briquettes for Grade A2 issued by the Korea Forest Research Institute, except the density. Wood briquettes made of mata buaya by using the three types of starch adhesives generally had better properties than all other types of wood briquettes. The interaction of mangrove wood species and the types of starch adhesive had a significant effect on the properties of wood briquettes, except for volatile matter and calorific value for which they had no significant effect. The use of wood briquettes from mangrove wood branches contributes to sustainable forest management and maintains the ecological function of mangrove forests while providing environmentally friendly alternative energy for households as a source of fuel/energy. Furthermore, future research is needed, such as investigating the optimal pressing pressure needed to achieve higher density of the wood briquettes.

The utilization of renewable energy derived from biomass is one of the initiatives in producing alternative energy to lessen reliance on fossil fuels. Wood briq