Natural Fiber-reinforced Biocomposites Research Articles

Effect of Mercerization on Mechanical Properties of <i>Grewia Optiva </i>Natural Fiber Polymer Composites

The concerns towards sustainable development have triggered the need of adopting biodegradable products in different applications. The natural fibers are being widely explored in the field of composites for various applications. Sustainable architecture is also seeking the research and development of new materials to minimize the negative environmental effect of the traditional structural materials. A bast fiber obtained from Grewia Optiva (G.O.) tree is abundantly available in the sub-Himalayan terrains and is still underutilized in the field of biocomposites. The promotion of G.O. fiber in fabrication of biocomposites may give a source of income and employment to rural hilly populations. This research work utilizes the G.O. fiber collected from the Okhalkanda block of Nainital district of Uttarakhand to develop biocomposites. The effect of mercerization on the water absorption behavior and mechanical properties has been also studied. It is found that the treatment of fibers with NaOH reduces the water absorption tendency of G.O. Natural Fiber Reinforced Biocomposites (NFRB) upto 41.05% and the mechanical properties are also improved by appreciable amount. The tensile and flexural strength obtained are 141.45 MPa and 109.84 MPa respectively for mercerized fiber reinforcement. Impact strength and mode-I fracture toughness have been recorded as 11.97 KJ/m2 and 1.85 MPa√m respectively. SEM images of fractured surfaces indicate good bonding of mercerized fibers as compared to untreated fibers with epoxy matrix. Hence the Grewia Optiva biocomposites have potential to be used in different architectural applications like wall panels, false ceilings, doors, windows, etc.

Enhancing Packaging Sustainability with Natural Fiber Reinforced Biocomposites: An outlook into the future

Packaging across diverse sectors like food, FMCG products, pharmaceuticals, cosmetics, and electronics predominantly relies on petroleum-based materials. These petroleum-based non-renewable resources significantly impact the environment throughout their life cycle, emitting polluting gases, demanding energy-intensive manufacturing, and causing air, water, and land pollution during disposal. These problems can be minimized by using eco-friendly materials such as materials made from natural fibres, and agricultural waste that is biodegradable in nature. Natural fibre-reinforced biocomposite materials have a high potential to be used in sustainable packaging applications due to their lower environmental impact compared to petroleum-based materials. However, the use of biocomposites is very limited in the packaging sector and growing exponentially. Recently, agriculture waste fibres have been used for the development of various biocomposites-based packaging. In this paper, prior work has been analysed to identify the impact associated with petroleum-based packaging materials, advantages and potential of natural fiber-reinforced biocomposites in the packaging sector, manufacturing techniques, recent development, challenges, and prospects have been discussed.

Restructuring the Interface of Silk-Polycaprolactone Biocomposites Using Rigid-Flexible Agents.

Natural fiber-reinforced biocomposites with excellent mechanical and biological properties have attractive prospects for internal medical devices. However, poor interfacial adhesion between natural silk fiber and the polymer matrix has been a disturbing issue for such applications. Herein, rigid-flexible agents, such as polydopamine (PDA) and epoxy soybean oil (ESO), were introduced to enhance the interfacial adhesion between Antheraea pernyi (Ap) silk and a common medical polymer, polycaprolactone (PCL). We compared two strategies of depositing PDA first (Ap-PDA-ESO) and grafting ESO first (Ap-ESO-PDA). The rigid-flexible interfacial agents introduced multiple molecular interactions at the silk-PCL interface. The "Ap-PDA-ESO" strategy exhibited a greater enhancement in interfacial adhesion, and interfacial toughening mechanisms were proposed. This work sheds light on engineering strong and tough silk fiber-based biocomposites for biomedical applications.

Mussel-inspired reinforcement of a biodegradable aliphatic polyester with bamboo fibers

Natural fiber-reinforced biocomposites displaying light weight, low thermal conductivity and reduced environmental footprint are increasingly relevant in structural, packaging, cementitious and masonry materials. However, the poor interfacial compatibility between fibers and typical polymers has limited the development of mechanical strength and water resistance. Here, we report a green, facile and effective method inspired by nature to promote interfacial adhesion in biocomposites based on a biodegradable aliphatic polyester (polybutylene succinate, PBS). For this purpose, PBS was reinforced with bamboo fibers modified with (3-aminopropyl) triethoxysilane and polydopamine (PDA). The PDA deposition and covalent adhesion with the fibers were promoted by self-polymerization and Michael addition and/or Schiff based secondary reactions. A distinct improvement in reinforcement was achieved together with gains in performance, including tensile strength (70%), tensile modulus (25%), flexural strength (37%), flexural modulus (24%) and impact strength (63%). The results far exceeded those measured for other fiber-reinforced biocomposites while simultaneously introduced water resistance.

Exploring the possibilities of FDM filaments comprising natural fiber-reinforced biocomposites for additive manufacturing

<abstract> In recent years, with the recent advancements in the field of additive manufacturing, the use of biobased thermoplastic polymers and their natural fiber-reinforced biocomposite filaments have been rapidly emerging. Compared to their oil-based counterparts, they provide several advantages with their low carbon footprints, ease of reusability and recyclability and abundancy, and comparable price ranges. In consideration of their increasing usage, the present study focused on the development and analysis of biocomposite material blends and filaments by merging state-of-the-art manufacturing and material technologies. A thorough suitability study for fused deposition modeling (FDM), which is used to manufacture samples by depositing the melt layer-by-layer, was carried out. The mechanical, thermal, and microstructural characterization of birch fiber reinforced PLA composite granules, in-house extruded filaments, and printed specimens were investigated. The results demonstrated the printability of biocomposite filaments. However, it was also concluded that the parameters still need to be optimized for generic and flawless filament extrusion and printing processes. Thus, minimal labor and end-products with better strength and resolutions can be achieved. </abstract>

Surface Modification of Flax Fibers for Manufacture of Engineering Thermoplastic Biocomposites

The aim of this feasibility study is to develop application-oriented natural fiber-reinforced biocomposites with improved mechanical and durability performance. The biocomposites were manufactured via a film-stacking process of epoxy-coated flax textiles and polyamide 6 (PA6). The fabricated biocomposites were subjected to thermo-oxidative ageing for 250, 500 and 1000 h and tested with regard to tensile properties. The results show that the biocomposites with epoxy-coated flax fibers possess considerably higher tensile properties compared with the reference specimens under all tested conditions.

Effect of the Polyethyleneimine Coating on the Bending Properties of the Natural Fiber-Reinforced Biocomposites

Effect of the Polyethyleneimine Coating on the Bending Properties of the Natural Fiber-Reinforced Biocomposites

Properties of natural fiber-reinforced biobased thermoset biocomposites: Effects of fiber type and resin composition

Four biobased thermosets were used as matrices for manufacturing natural fiber-reinforced biocomposites with high performance and biobased contents. The thermosets included acrylated epoxidized soybean oil (AESO), AESO with methacrylated isosorbide (MI) as a comonomer (MI-AESO), methacrylated AESO with MI (MI-MAESO), and MI resins. Bamboo fibers (BFs) and hemp fibers (HFs) were chosen as representatives for natural fibers in the biocomposites. The synergistic effects of fiber type and resin composition on the obtained composites were revealed through analyses of characteristics of the fibers and the resins as well as measurements of densities, flexural properties, dynamic mechanical properties, and water absorption of the composites. Results indicated that resin composition, chemical structure, and crosslinking density of the matrices were closely associated with the performance of the biobased thermosets and hence the resulting biocomposites. The HF-reinforced composites achieved much superior flexural strengths, flexural moduli, and water resistance than the BF-reinforced composites.

Mechanical, Dynamic Mechanical and Thermal Properties of Banana Fiber/Recycled High Density Polyethylene Biocomposites Filled with Flyash Cenospheres

This study presents the preparation of Natural fiber-reinforced biocomposites based on Recycled High Density Polyethylene (RHDPE)/Banana Fiber (BF)/Fly ash Cenospheres (FACS) and aims to increase the economic value of these waste materials. Maleic anhydride grafted HDPE (MA-g-HDPE) was used as a compatibilizer to increase the dispersion of fibers into the polymer matrix as well as to increase the compatibility between the matrix and fillers. Variation in mechanical, thermal and dynamic mechanical properties with the addition of FACS in RHDPE/BF composites was investigated. It was observed that 7.5 wt% FACS, 30 wt% BF and 3 wt% MA-g-HDPE within RHDPE matrix resulted in an increase in tensile strength to 17%, tensile modulus to 188%, flexural strength to 38%, flexural modulus to 159% and hardness to 37% as compared with the RHDPE matrix. Significant enhancement in the thermal stability of the RHDPE/BF biocomposites was also observed in presence of FACS under thermogravimetric analysis. The morphology of the prepared biocomposites has been examined by using scanning electron microscopy. Dynamic mechanical analysis tests revealed an increase in storage and loss modulus of the biocomposite system. The use of such recycled material, agricultural and industrial wastes increased the properties of the final product suggesting their use to be a good alternative in the production of polymeric composites.

Biocomposites: Their multifunctionality

During the last decade, tissue engineering has shown a considerable promise in providing more viable alternatives to surgical procedures for harvested tissues, implants and prostheses. Due to the fast development on nano- and biomaterial technologies, it is now possible for doctors to use patients' cells to repair orthopaedic defects such as focal articular cartilage lesions. In order to support the three-dimensional tissue formation, scaffolds made by biocompatible and bioresorbable polymers and composite materials, for providing temporary support of damaged body and cell structures, have been developed recently. Although ceramic and metallic materials have been widely accepted for the development of implants, their non-resorbability and necessity of second surgical operation (like for bone repair), which induce extra pain for the patients, limit their wide applications. The development of different types of biocomposites for biomedical engineering applications is described. These biocomposites include (i) basic biomaterials; (ii) natural fiber-reinforced biocomposites and (iii) nanoparticle-reinforced biocomposites. Their multifunctionality is discussed in terms of the control of mechanical properties, biodegradability and bioresorbability.