This study investigates the mechanical, thermal, and wears characteristics of eco-friendly composite materials (designated as N1 to N5) with varying ratios of silicon nitride (biogenic Si3N4) and biochar along with jute and kenaf microfiber. The primary aim of this research study was to investigate the suitability of low cost biomass derived functional ceramic fillers in composite material instead of high cost industrial ceramics. Both the bio carbon and biogenic Si(3)N(4 )were synthesized from waste sorghum husk ash via pyrolysis and thermo-chemical method. Further the composites are prepared via mixed casting process and post cured at 100 degrees C for 5 h. According to results, the mechanical properties show a consistent improvement, attributed to the contributions of biogenic Si3N4. Moreover, the specific wear rate decreases progressively, with a larger biogenic Si(3)N(4 )and bio carbon filler %. The presence of biochar acts as solid lubricant and offered balanced friction coefficient. The composite N4 attained maximum mechanical properties including tensile (110 MPa), flexural (173 MPa), impact (6.1 J), hardness (82 shore-D), compressive (138 MPa) and lap shear strength (16 MPa). On contrary, the composite N5 attained least thermal conductivity of 0.235 W/mK, Sp. Wear rate of 0.00545 with COF of 0.26. Similarly, the scanning electron microscope (SEM) analysis revealed highly adhered nature of fillers with matrix, indicating their cohesive nature indicating the strong interfacial adhesion between the fillers and the matrix, attributed to the presence of biochar, which enhances mechanical interlocking and provides functional groups that promote chemical bonding with the polymer matrix, leading to improved load transfer efficiency and overall composite performance. Moreover, thermal conductivity values exhibit a marginal decline with the presence of biogenic Si(3)N(4)and biochar. Overall, the study demonstrated that biomass-derived functional fillers are capable candidates for providing the required toughness and abrasion-free surfaces, as evidenced by the increased impact strength, improved wear resistance, and enhanced durability observed in treated specimens compared to the control samples.This approach offers both economic and environmental benefits by reducing human exposure to hazardous pollutants through the utilization of biomass-derived materials, which help divert waste from landfills, lower air pollution caused by burning conventional plastics, and minimize soil contamination from non-biodegradable waste. In addition, the developed natural fiber-reinforced composites exhibited competitive mechanical performance compared to conventional industrial ceramic-reinforced composites, demonstrating comparable strength, enhanced toughness, and improved damping properties while offering the advantages of lower density, biodegradability, and cost-effectiveness. These findings highlight the potential of biomass-derived fillers as sustainable alternatives in structural applications.

The use of geo-synthetics, such as geotextiles, has the potential to enhance the inherent engineering and geotechnical properties of subgrade soils that exhibit poor conditions. The use of geotextiles in pavement construction has many advantages, including enhanced subgrade strength and the ability to construct flexible pavements that are both efficient and cost-effective since it reduces the pavement thickness. In the realm of flexible pavement system development, the significance of subgrade soils and their inherent characteristics, including permeability and strength, is well acknowledged. The study included conducting experiments to investigate the use of geo-polymeric materials like geo-textiles on improving the mechanical properties of the subgrade soils under varying moisture conditions. Geotextiles possess good tensile resistance as it is made up of good polymeric material like polyester, polypropylene and polyethylene. Geotechnical tests including grain size analysis, Atterberg limits, California bearing ratio test, and compaction tests, were conducted. CBR tests and UCS tests were conducted by placing the geotextiles in a singular arrangement at various depths and subjecting them to both soaked and unsoaked conditions to assess the soil's strength. The results demonstrate that the use of geosynthetic reinforcement in the soil effectively enhances the strength of the subgrade across various soil types. The optimal performance of geo-synthetics in relation to their placement inside the CBR mold was found to be at a distance of 1/3 of the mold's height from the top. This placement outperformed the alternative distances of 1/2 and 2/3 of the mold's height.

This research aims to analyze the biodegradation dynamics of a tertiary composite blend, including High-Density Polyethylene (HDPE), starch and linen fiber, and their combined effect on decay processes in authentic environmental settings. It investigates the relationship between fiber content and decomposition rates, details the biodegradation mechanisms, and evaluates the reactive profiles of the involved constituents. Decay kinetics and the biodegradation mechanism of three formulations: HDPE60S40, HDPE60S20F20, and HDPE60S30F10, representing composites with 60 % HDPE, complemented by 40 %, 20 % starch and 20 %, 10 % linen fiber, respectively, are examined. HDPE60S30F10 is noted for its superior biodegradation rates, showing a 1.2 % weight loss in soil and 9.89 % in marine conditions and an increased resistance to shearing forces, whereas HDPE60S40 recorded a weight loss of 0,63 % in soil and 2.59 % in seawater against 1,7 % and 6.64 % in soil and seawtaer, respectively recorded with HDPE60S20F20. Density Functional Theory (DFT) and Molecular Dynamics (MD) simulations complement these findings, presenting HDPE60S40 as the most rigid, HDPE60S20F20 as the most ductile with a bulk modulus of 13.34 GPa, and HDPE60S30F10 exhibiting the best shear resistance with a shear modulus of 12.48 GPa. Scanning Electron Microscopy (SEM) and Fourier-Transform Infrared Spectroscopy (FTIR) analyses confirm microbial involvement and significant surface erosion, particularly indicating particularly starch degradation. The results suggest that integrating linen fiber into the composites enhances biodegradation.

This study investigates the potential of utilizing green chemically treated spent coffee grounds (SCGs) as micro biofiller reinforcement in Poly-3-hydroxybutyrate- co -3-hydroxyvalerate (PHBV) biopolymer composites. The aim is to assess the impact of varying SCG concentrations (1 %, 3 %, 5 %, and 7 %) on the functional, thermal, mechanical properties and biodegradability of the resulting composites with a PHBV matrix. The samples were produced through melt compounding using a twin-screw extruder and compression molding. The findings indicate successful dispersion and distribution of SCGs microfiller into PHBV. Chemical treatment of SCG microfiller enhanced the interfacial bonding between the SCG and PHBV, evidenced by higher water contact angles of the biopolymer composites. Field Emission Scanning Electron Microscopy (FE-SEM) confirmed the successful interaction of treated SCG microfiller, contributing to enhanced mechanical characteristics. A two-way ANOVA was conducted for statistical analysis. Mass losses observed after burying the materials in natural soil indicated that the composites degraded faster than the pure PHBV polymer suggesting that both composites are biodegradable, particularly at high levels of spent coffee grounds (SCG). Despite the possibility of agglomeration at higher concentrations, SCG incorporation resulted in improved functional properties, positioning the green biopolymer composite as a promising material for sustainable packaging and diverse applications.

Growing concerns over the threat to the geoenvironment from the disposal of municipal solid waste and industrial byproducts created an alarming situation. Hence, their utilization as Anthropogenic (manmade) Resources (read as AnthRes), especially those being generated in millions of tons, such as landfill-mined-soil-likefractions (LFMSF) and red mud (RM), become unavoidable. However, the existing utilization pathways raise questions over their environmental sustainability as they would not control the leaching of microplastics, salts, and heavy metals from these materials. To overcome this situation, the utilization of LFMSF and RM as fillers in manufacturing the polymer composites, which can isolate them from the outside environment, was proposed. In this context, the influence of the most significant parameters like (i) filler content (FC) and (ii) melt-mixing processes on the mechanical, thermal, and morphological characteristics of polypropylene composites were investigated. It was observed that FC and the presence of fiber-like organic matter in LFMSF would significantly influence the mechanical properties of the composites. Subsequently, mathematical models that can be employed for predicting the influence of the above-mentioned parameters on the mechanical properties were developed. Moreover, batch experiments were performed to obtain the leaching characteristics, which revealed that the concentrations of leachable elements from the composites reduced by over 98% as compared to their respective fillers indicative of effective bonding between the polypropylene matrix and filler particles. Hence, the present study established that the LFMSF and RM can be utilized as AnthRes in polymer composites for sustainable development without harming the geoenvironment.