Derived from Coir coconut waste, coir fiber offers an environmentally friendly response to ecological challenges in various industries. Its application aligns with achieving Sustainable Development Goals (SDGs), such as eliminating extreme poverty, ensuring food security, and promoting decent employment and economic expansion. It also fosters environmentally friendly consumption and production, mitigates global warming, and conserves biodiversity. The study involves a comprehensive review of current literature, examining the methodologies including extraction techniques, surface modifications, and manufacturing processes like hand layup, casting, compression molding, hot pressing, and injection molding. The analysis identifies key improvements in mechanical, thermal, and physical properties of coir fiber composites, particularly enhanced tensile strength, thermal stability, and reduced water absorption due to chemical treatments. This confirms previous findings and contributes toward enhancing our understanding that coir fiber is extensively utilized in multiple industries, including housing, construction, transportation, biomedical, wrapping, electrical power, communication technology, biofuel, and bioenergy due to their natural abundance, affordability, ease of shaping, superior durability, and eco-friendly characteristics. Another crucial practical implication is that coir fiber and its composites offer numerous advantages that have significant consequences for the development of coir fiber in various fields.

This paper presents an approach for hydrolyzing cellulose nanocrystals from oil palm empty fruit bunch (OPEFB) presented through hydrochloric acid hydrolysis under sonication–hydrothermal conditions. Differences in concentration, reaction time, and acid-to-cellulose ratio affect toward the yield, crystallinity, microstructure, and thermal stability were obtained. The highest yield of cellulose nanocrystals up to 74.82%, crystallinity up to 78.59%, and a maximum degradation temperature (T_max) of 339.82 °C were achieved through hydrolysis using 3 M HCl at 110 °C during 1 h. X-ray diffraction analysis indicated a higher diffraction peak pattern at 2θ = 22.6° and a low diffraction peak pattern at 2θ = 18°. All cellulose nanocrystals showed a crystalline size of under 1 nm, and it was indicated that the sonication–hydrothermal process could reduce the crystalline size of cellulose. Infrared spectroscopy analysis showed that a deletion of lignin and hemicellulose was demonstrated in the spectrum. Cellulose nanocrystal morphology showed a more compact structure and well-ordered surface arrangement than cellulose. Cellulose nanocrystals also had good thermal stability, as a high maximum degradation temperature was indicated, where CNC-D1 began degrading at temperatures (T₀) of 307.09 °C and decomposed (T_max) at 340.56 °C.

This research improves the strength of plastic using avocado seed starch and PLA. The effect of blending avocado seed starch and PLA was optimized using the RSM approach by using two variables: water absorption and biodegradability. Mixing them using RSM gave the best result: 1.8 g of starch and 3 g of PLA. Degradable plastic has a tensile strength of 10.1 MPa, elongation at a break of 85.8%, and a Young’s modulus of 190 MPa. Infrared spectroscopy showed that the plastic had a -OH bond at 3273.20 cm⁻¹, 3502.73 cm⁻¹, and 3647.39 cm⁻¹, a CH₂ bond at 2953.52 cm⁻¹, 2945.30 cm⁻¹, and 2902.87 cm⁻¹, a C=C bond at 1631.78 cm⁻¹, and a C-O bond at 1741.72 cm⁻¹. The plastic decomposed in the soil. It was organic and hydrophilic. Thermal tests demonstrated that the plastic can withstand heat well, losing weight at 356.86 °C to 413.64 °C, forming crystals and plastic melts at 159.10 °C—the same as PLA. In the melt flow test, the sample melted before measurement, and was therefore not measurable—process conditions affected it. A water absorption of 5.763% and biodegradation rate of 37.988% were found when the samples were decomposed for 12 days. The starch and PLA fused in the morphology analysis to form a smooth surface. The RSM value was close to 1. The RSM gave the best process parameters.

The high concentration of metallic components in the pad composite improves breaking ability at elevated temperatures and frequencies, bolstering the automobile's braking system. The brake pad operates through friction mechanisms, generating PM 10 and PM 2.5 particulate matter that is emitted into the atmosphere, adversely affecting the well-being of humans and animals. Therefore, eco-friendly materials like natural fiber and organic particles are being used as substitutes for the metal in brake pads. However, natural fibers and particles exhibit unique characteristics when interacting with other materials, presenting significant challenges in brake pad composites such as variations in physical properties, limited thermal resistance, and potential degradation at high temperatures and humid environments. These aspects play a crucial role and can affect the structural strength, wear resistance, and overall performance of composite brake pads, especially when operating under extreme braking conditions. This paper review critically discusses automotive braking systems, the benefits of non-natural fiber brake pads, the process of particle emission formation, the components and manufacturing factors of composite brake pads, and the environmentally friendly qualities of brake pads. This study provides an exciting opportunity to advance our knowledge of the presence of natural fibers and organic particles in composite brake pads, which greatly improves the performance of automotive brake systems because they have super physical and mechanical properties, as well as great tribological and thermal endurance. Moreover, eco-friendly brake pads are typically biodegradable, which helps reduce ecological damage, minimize health concerns for humans and animals, and promote a sustainable automobile sector. Furthermore, eco-friendly brake pads show great potential for further advancement in reducing pollutant emissions and enhancing performance.

Sago starch and cellulose fiber can be used as a raw material for making degradable plastics to replace commercial plastics. This research used corn cob fiber and sugarcane bagasse fiber as filler to improve the properties of degradable plastic. The research method consists of several stages, cellulose fiber preparation, degradable plastic synthesis and plastic characterization. The result showed tensile strength of plastic with corn cob and sugarcane bagasse filler was 6.37–11.5 MPa and 9.70–16.47 MPa, respectively. The compound composition test through Fourier Transformation Infra-Red (FTIR) exhibited hydrophilic behavior, hence plastic easily degraded by soil. Differential Scanning Calorimetry (DSC) shows that degradable plastic with corn cob fiber filler denoted a melting point of 163.84 ℃, while sugarcane bagasse fiber filler at 163.47 ℃. Thermogravimetric Analysis (TGA) analysis indicated degradable plastic had a good thermal stability. Scanning Electron Microscopy (SEM) exhibited few white lumps and indentations on the surface, indicating that the solubility was not homogeny and could be due to the influence of stirring process. In term of ability to absorb water, both plastic with fiber filler had a small water absorption with a range of 5–6%. Melt Flow Rate (MFR) analysis of degradable plastics with corn cob fiber and sugarcane bagasse pointed the value that was suitable for injection molding processing technique. The degradation of both plastics ranged about 50–85 days to completely decomposed naturally in soil, as supported by FTIR analysis.