In the contemporary world, natural fibers reinforced polymer composite (NFRPC) materials are of great interest owing to their eco-friendly nature, lightweight, life-cycle superiority, biodegradability, low cost, noble mechanical properties. NFRPCs are widely applied in various engineering applications and this research field is continuously developing. However, the researchers are facing numerous challenges regarding the developments and applications of NFPRCs due to the inherent characteristics of natural fibers (NFs). These challenges include quality of the fiber, thermal stability, water absorption capacity, and incompatibility with the polymer matrices. Ecological and economic concerns are animating new research in the field of NFRPCs. Furthermore, considerable research is carried out to improve the performance of NFRPCs in recent years. This review highlights some of the important breakthroughs associated with the NFRPCs in terms of sustainability, eco-friendliness, and economic perspective. It also includes hybridization of NFs with synthetic fibers which is a highly effective way of improving the mechanical properties of NFRPCs along with some chemical treatment procedures. This review also elucidates the significance of using numerical models for NFRPCs. Finally, conclusions and recommendations are drawn to assist the researchers with future research directions.

Natural fiber reinforced composites: Sustainable materials for emerging applications

Novel biopolymer-based sustainable composites for food packaging applications: A narrative review

4D printing of shape memory polymer composites: A review on fabrication techniques, applications, and future perspectives

Advancements in polymer science and engineering have helped the scientific community to shift its attention towards the use of environmentally benign materials for reducing the environmental impact of conventional synthetic plastics. Biopolymers are environmentally benign, chemically versatile, sustainable, biocompatible, biodegradable, inherently functional, and ecofriendly materials that exhibit tremendous potential for a wide range of applications including food, electronics, agriculture, textile, biomedical, and cosmetics. This review also inspires the researchers toward more consumption of biopolymer-based composite materials as an alternative to synthetic composite materials. Herein, an overview of the latest knowledge of different natural- and synthetic-based biodegradable polymers and their fiber-reinforced composites is presented. The review discusses different degradation mechanisms of biopolymer-based composites as well as their sustainability aspects. This review also elucidates current challenges, future opportunities, and emerging applications of biopolymeric sustainable composites in numerous engineering fields. Finally, this review proposes biopolymeric sustainable materials as a propitious solution to the contemporary environmental crisis. • Use of biopolymers has emerged as a new paradigm of the ecological conservation. • Biopolymeric composites are easily degraded under the possible source of degraded environment. • Biopolymers have found their applications in biomedical, food, electronics, cosmetics and other emerging fields. • Further understanding on their mode of action through this comprehensive review will imparts knowledge. 

Biopolymeric Sustainable Materials and their Emerging Applications

The research interest in sustainable and eco-friendly materials based on natural sources has increased dramatically due to their recyclability, biodegradability, compatibility, and nontoxic behavior. Nanocellulose contains chains of glucose residue and is an abundantly available green material. Recently, nanocellulose-based green composites are under extensive exploration and gained popularity among researchers owing to their lightweight, lost cost, low density, excellent mechanical and physical characteristics. These materials have also shown tremendous potential for applications in biomedical and numerous engineering fields. The mechanical properties of these materials play a vital role in effective utilization and their exploration for future applications. This review article comprehensively presents current developments, results, and findings in the arena of green and sustainable materials. Currently, the main problem is the large variability in their properties and qualities. Nanocellulose properties are influenced by various factors, including the fiber type, ecological conditions, manufacturing methods, and any alteration of the fiber surface. Finally, the review incorporates future challenges and opportunities in the field of nano cellulosic materials.

Recent advances in nanocellulose-based different biomaterials: types, properties, and emerging applications

The aircraft industry is always seeking materials with excellent mechanical properties and good strength to weight ratio. Fiber metal laminates (FMLs) are the emerging class of hybrid composite materials consisting of fiber-reinforced polymers (FRP) plies and metal sheets. Aircraft parts are subjected to different types of mechanical loading during operation. Combining the properties of FRPs and metals provides excellent resistance to impact as well as improves the fatigue performance of the aircraft. In this study, aluminum 7075-T6 sheets were used to fabricate FMLs with varying fiber reinforcements. These sheets were treated with different surface and chemical treatment processes. The short beam shear test is utilized in this work that gives practical information on interlaminar shear strength (ILSS) and it can also be employed in real design applications. The results indicated that the ILSS of carbon fiber reinforced aluminum laminates (CARALL) was higher than glass-reinforced aluminum laminates (GLARE) and aramid-reinforced aluminum laminates (ARALL) at all displacement rates. The reason for the higher ILSS of CARALL is due to the stifness of carbon fiber and the strong adhesion of carbon with aluminum metal. However, ILSS for all three types of FMLs did not change significantly which shows that it is independent of displacement rates.

Interlaminar shear strength (ILSS) characterization of fiber metal laminates (FMLs) manufactured through VARTM process

Polystyrene (PS)/sepiolite clay nanocomposites were prepared via the melt extrusion technique using vinyl tri-ethoxy silane (VTES) as the compatibilizer and cross-linking agent. Mechanical, thermal, and flame-retardant properties of the newly developed polystyrene-based nanocomposites were determined. Surface morphology was investigated using scanning electron microscopy (SEM), examining the distribution of the filler in various compositions of fabricated composites. Structural analysis of the samples was carried out using the Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) techniques. Thermal stability was determined by thermal gravimetric analysis (TGA), showing a maximum 30.2 wt.% increase in residue by adding sepiolite clay. The results obtained from the dynamic mechanical analyzer (DMA) in terms of the storage modulus, loss modulus and damping factor exhibited better stress transfer rate and effective interfacial adhesion between the filler and the matrix. The higher filler loaded sample showed greater flame retardancy by decreasing the burning rate up to 48%.

/pdf/polystyrene-sepiolite-clay-nanocomposites-with-enhanced-ijlyvltx.pdf

Polystyrene-Sepiolite Clay Nanocomposites with Enhanced Mechanical and Thermal Properties

The article reports an experimental study on a non-tracking compound parabolic collector (CPC) with nanofluid and hybrid nanofluids (NFs). An experimental setup was fabricated having a concentration ratio of 4.17, 0.828 m2 collector area, 24° of half acceptance angle, and an evacuated tube receiver having 1.85 m length. Fluids like water and NFs have been investigated in CPC performance improvement, but current research deals with NFs and hybrid NFs in a CPC as rare studies are found on a CPC using NFs. The 0.010 and 0.015 wt% concentration were used of nanofluids (NFs) which were silica/water + ethylene glycol (SiO2)/(H2O + EG), and hybrid nanofluids of magnesium oxide + carbon black/water (MgO + CB/H2O) and carbon black + graphene nanoplatelets/water (CB + GNPs/H2O) at flow rates of 0.020, 0.015, and 0.010 kg/s. The experimentation was performed under real climate conditions of Taxila, Pakistan, and solar irradiance and ambient temperature were measured to determine the performance of the CPC in comparison to a simple base fluid which was water. The experimental results revealed that a maximum temperature difference of 8.5°C with an around thermal efficiency of 38.51% was achieved for hybrid pair of MgO + CB at a flow rate of 0.010 kg/s and volumetric concentration of 0.015 wt%. The efficiency variation using NFs (SiO2/EG + H2O) varies from 12.8% to 59.1% from lowest 0.010 kg/s to highest 0.020 kg/s flow rates, and volumetric concentrations (0.010 and 0.015 wt%) of nanoparticles. For similar experimental conditions, efficiency variation for (CB + GNPs) pair varies from 14.2% to 65.6% for aforementioned conditions. Efficiency variation from 15.3% to 66.3% was attained using MgO + CB in the base fluid of water for said flow rates and volumetric concentrations of nanoparticles. In addition, an efficiency enhancement of 24.3%, 30.8%, and 31.5% was observed for SiO2/EG + H2O, CB + GNPs/H2O, and MgO + CB/H2O, respectively, at maximum flow rates and volumetric concentration of nanoparticles as compared to water. Therefore, the usage of hybrid-based NF in the CPC is beneficial in terms of efficiency enhancement, and it will bring young research workers to get deep into this field to bring revolution in the area of solar energy.

/pdf/performance-evaluation-of-compound-parabolic-solar-collector-3omrydb7.pdf

Muhammad Ihsan Shahid

Papers

Interlaminar shear strength (ILSS) characterization of fiber metal laminates (FMLs) manufactured through VARTM process

Polystyrene-Sepiolite Clay Nanocomposites with Enhanced Mechanical and Thermal Properties

Performance evaluation of compound parabolic solar collector using different nanofluids: An experimental study