•Enhancement of flame retardancy and smoke suppressant of natural fibre Elium® composite laminates using intumescent thermal resistive mats containing expandable graphite was performed ...successfully.•While higher expansion ratios of EG particles in the composite lead to greater flame resistivity and reduction of smoke, the modulus decrease proportional to the increase of EG exfoliation ratio.•The bending strength of composites was found to increase as compared to that of the Control composite and the glass transition temperature was seen to increase with EG of lower expansion ratios in the coating material.
This investigation studied the utilization of intumescent thermal resistive mats to provide surface protection to the core natural fibre-reinforced Elium® composite structural integrity. The intumescent mats contained flame retardant (FR) i.e. expandable graphite (EG) with four different expansion ratios and alumina trihydrate (ATH). All natural fibre thermoplastic composites were fabricated using a resin infusion technique. The impact of char thickness and chemical compositions on the flammability and smoke properties was investigated. It was found that surface protection significantly reduced the peak heat release rate, total smoke release, smoke extinction area and CO2 yield, and substantially enhanced UL-94 rating, time to ignition and residual char network, depending on the EG exfoliation ratio, ATH and mineral wool fibre. The glass transition temperature increased for the FR composites containing EG with lower expansion ratio. Inclusion of intumescent mats increased the strength of the composites while it had a negative effect on the modulus.
•Sisal fibre obtained by decortication from sisal plants widely found in East Africa.•It possess super engineering mechanical properties like jute and hemp fibres.•Tensile strength, modulus and ...elongation at break are comparable to jute and flax.•Adding in thermosets, thermoplastics and biopolymer improves mechanical strength.•Sisal polymer composites impart revolution in structural and building industries.
Recently, growing environmental impact associated with production, disposal and recycling of synthetic fibre based polymer composites triggers the development of ecofriendly composite for various applications such as automotive, marine, chemical, Infrastructure, sporting goods etc. Among many natural fibres like kenaf, jute, oil palm, cotton, flax, banana and hemp, sisal are gaining attention as they are abundantly available, cheaper, eco-friendly and possess remarkable and satisfactory mechanical properties to hemp, banana and jute. Sisal fibre will play a key role to fabricate a varied range of structural and non-structural industrial products with different polymer matrix. This review article deals the mechanical properties of sisal fibre and the several factors influencing the mechanical properties of its polymer composites, such as fibre loadings, fibre length, fibre architecture, chemical treatments and hybridization by incorporating different natural/synthetic fibre/fillers or additive, according to the application and strength requirements. Attempt also been made to investigate the effect of water absorption, chemical concentration, exposure time, filler weight% and individual fibre loading % in the hybrid configuration on the mechanical properties. Overall present review article was designed to explore, highlights and gathered the previous reported studies directing the mechanical properties of sisal fibre and its polymer composites to provide a perfect source of data and literature for doing future research to reveal it as construction and building materials like synthetic fibres.
Recently, scientists are facing major obstacles in terms of selecting compatible filler materials for the sake of improving the performance of polymeric composite materials. Therefore, a high ...interest has been devoted to the development of polymeric composites reinforced with nano fillers. The nano reinforced particle’ polyester matrix composites (PMCs) are widely utilized in the manufacturing industries due to their high fracture toughness, light weight, superior strength to weight ratio, high tensile properties, high fatigue resistance, and improved corrosion resistance to severe environments. This article presents a review of the different manufacturing processes and the various reinforcing elements used throughout the preparation of PMCs. The affecting conditions during manufacturing of reinforced particle PMCs are deliberated in a manner to better understand the usefulness of incorporating reinforcing particles in PMCs. The natural fibres utilized as reinforcements in polyester composite materials are thoroughly reviewed including cotton, banana, jute, kenaf, coir, hemp, and sisal. The nano particles reviewed in this paper are nano clay, carbon nano tubes, nano graphene and nano graphene oxide. The reviewed material systems forming polyester nano composites are analysed separately and jointly, showing their scientific developments. The general mechanical characteristics as tensile, compression, fatigue, hardness, and flexural strength, etc. reported by other researchers are investigated with a main objective to demonstrate the quantity of reinforcement used and the corresponding improvements achieved after processing. Finally, the presented review aims to open the horizons towards applications and possible future prospects of natural fibres reinforced polymeric nano composites.
To date, the literature has focused on synthetic fibre-reinforced composites, but it has not adequately addressed the unique properties that differentiate natural from synthetic fibres, such as their ...natural variation in microstructure and composition across species. This review paper proposes a critical overview of the current state of 3D printing of natural fibre-reinforced composites or biocomposites for mechanical purposes, as well as an overview of their role in 4D printing for stimuli-responsive applications. The paper is structured as follows: after the first part recalling the specificities of natural fibres and their associated composites, the two main sections are each divided into two parts presenting an analysis of the available data to provide fundamental understandings and a discussion and outlook for the future.
Natural discontinuous fibre-reinforced polymers exhibit moderate mechanical properties compared to composites manufactured by conventional processes due to specific factors of the 3D printing process, such as high porosity, low fibre content, and a very low fibre-aspect ratio (L/d). Hygromorph BioComposites (HBC) are categorized into a new class of smart materials that could be used for 4D printing of shape-changing mechanisms. Fibre content, fibre orientation control, and fibre continuity are outlined in relation to known challenges in actuation performance.
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•The current state of the art on 3D and 4D printing of biocomposites based on natural fibres was achieved.•The 3D printing data was delivered from the production of the filaments to the tensile properties of the printed biocomposite.•The 4D printing data of biocomposites were analyzed in terms of actuation characterization.•The relationship between slicing/printing parameters, microstructure and mechanical or actuation performance was analyzed.•The future prospects on 3D/4D printing of biocomposites based on natural fibres were discussed.
Conventional methods of enhancing the creep resistance of polyvinyl chloride (PVC) often compromise its resilience. This study proposes a novel strategy to achieve a balance between creep resistance ...and resilience in PVC-matrix composites by incorporating epoxidised soybean oil-modified collagen fibres (MCFs). A comparative analysis of creep and recovery behaviour was conducted among MCF/PVC, pure PVC, and other conventional modified systems. Results revealed that MCF/PVC exhibited a lower total creep strain (12.82%) than pure PVC and a higher recoverable deformation (10.80%) than the other conventional modified systems. Moreover, MCF/PVC had the longest predicted creep lifetime among all the modification systems, which was 103 times longer than that of pure PVC. These improvements were attributed to the natural multidirectional and hierarchical structure of MCF, which hindered the movement of PVC chains and provided sufficient gaps for recoverable deformation. This work provides a new perspective on developing resilient creep-resistant modifications of polymers by leveraging the structural advantages of natural products.
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•The balance between creep resistance and resilience in composites was achieved.•Collagen fibres (CFs) with a multidirectional and hierarchical structure were prepared.•MCF/PVC was successfully prepared by blending PVC with modified CF (MCF).•The mechanism of resilient creep-resistant modification of PVC was revealed.•MCF/PVC exhibited good comprehensive performance and promising application prospects.
Recently, interest has been increasing in natural fibres as composite reinforcing fillers for polymer-based filaments manufactured with the Fused Deposition Modeling (FDM) process, despite their ...moderate mechanical properties compared to pure polymer.
An innovative way was proposed in the present work to optimize the mechanical properties of biocomposites. It was based on novel continuous flax fibre/PLA (cFF/PLA) composite filaments made with a customized co-extrusion process and printed with a simple and affordable printing machine. The microstructure of the printed cFF/PLA biocomposite evidenced a homogeneous distribution of yarn within the cross section, while the twisted flax yarn led to fibre-rich areas at mesoscale. The cFF/PLA showed tensile modulus and strength values that exceeded the only available published result on continuous natural fibre printed composites by >4.5 times. Tensile properties were in the same range as those for continuous glass fibre/PolyAmide (PA) printed composites, paving the way for the use of biocomposites in structural applications. Their weakest point was their transverse properties that remained poorer than similar flax/PLA thermocompressed composites.
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•Fused Filament Fabrication of Continuous flax fibre/PLA biocomposites was performed.•Microstructure of filaments and printed samples was characterized.•Longitudinal and transverse mechanical behaviour and properties were evaluated.•Outstanding longitudinal mechanical properties were obtained compared to current printed biocomposites.
► Nature of the fibres controls the mechanical and the tribological behaviour of the composites. ► There is no remarkable correlation between the mechanical and tribological performance of major ...polymeric composites. ► Natural fibre polymeric composites suffer from high friction coefficient. ► The use of water as lubricants deteriorate the wear performance of synthetic fibre/polymer composites.
In this article, a comprehensive literature review on the mechanical and tribological behaviour of polymeric composites based on natural fibres is introduced. The effects of volume fraction, orientations, treatments and physical characteristics of different types of natural fibres on the mechanical and tribological properties of several thermoset and thermoplastic polymers are addressed. The effects of the tribological operating parameters (applied load, sliding velocity and sliding distance) on the frictional and wear performance of natural fibre polymer composites are demonstrated. The collected date and analyses revealed that volume fraction, orientations, type of treatment and physical characteristics of the natural fibres significantly influence the mechanical and tribological behaviour of composites. The most influence key in designing natural fibre/polymer composite is the interfacial adhesion of the fibre with the matrix. NaOH chemical treatment found to be the most useful treatment method to enhance the interfacial adhesion of the natural fibres with the matrix, while other techniques exhibited either no effect or deterioration on the fibre strength. Frictional characteristics of the natural fibre composites are poor and solid lubricants are recommended to reduce the friction coefficient of the materials.
Flax fibres offer performance capabilities comparable to glass fibres, thereby enhancing their potential in the biobased composites industry. However, these fibres have morphological defects ...affecting their mechanical features. In the present work, flax elementary fibres geometries with defects assessed by synchrotron X-ray microtomography were meshed to simulate a tensile test using finite element analysis. For the first time, the distribution of stresses in the vicinity of defects is revealed. The geometrical irregularities at the surface of the fibre and the delamination of cellulose layers within fibre cell wall turned out to concentrate stress up to 7.5 times compared to defect-free regions. These results demonstrate why flax fibres cannot reach their full potential in comparison to what could be expected from a structure mainly constituted from crystalline cellulose microfibrils, and why fracture in a composite is likely to initiate in those defect zones.
•Contribution of plant fibers in altering behavior of reinforced concrete (RC) is evaluated.•Wheat straw in concrete having varying flexure and shear rebars are considered.•To start with, practical ...implications of concrete pavements are taken into account.•Wheat straw in RC delayed crack initiation and enhanced its load capacity (up to 7.5%).•Concrete pavement with wheat straw can yield comparable design and better behavior.
Plant fibers (especially, wheat straw) are available surplus to requirements in sub-tropical regions. Many researchers have studied these fibers for non-structural applications. However, for civil engineering structural applications, in depth behavior of wheat straw reinforced concrete (WSRC) with steel rebars is not known. For this purpose, WSRC needs to be explored in detail for load bearing structures. This paper presents the contribution of plant fibers (i.e. wheat straw) in improving the behavior and capacity of reinforced concrete for structural applications. Reinforced concrete beam-lets with varying flexure and shear rebars, without and with inclusion of wheat straw, are experimentally investigated for studying the altered behavior due to fibers. In addition, to start with the practical implications, concrete pavements are considered. The study is concluded with an increase in flexural strength (up to 7.5%), energy absorption (up to 30.4%), and toughness indices (up to 11.1%) along with better crack arresting mechanism by incorporation of wheat straw in reinforced concrete. Also, concrete pavement containing wheat straw has comparable design with likely more durable and sustainable structure.
► Advancement in food packaging materials expected to grow. ► Natural fibre/nanoclay hybrid system have potential in food packaging. ► Hybrid composites for environmentally compatible food packaging ...materials.
The increasing demand for new food packaging materials which satisfy people requirements provided thrust for advancement of nano-materials science. Inherent permeability of polymeric materials to gases and vapours; and poor barrier and mechanical properties of biopolymers have boosted interest in developing new strategies to improve these properties. Research and development in polymeric materials coupled with appropriate filler, matrix-filler interaction and new formulation strategies to develop composites have potential applications in food packaging. Advancement in food packaging materials expected to grow with the advent of cheap, renewable and sustainable materials with enhanced barrier and mechanical properties. Nanoparticles have proportionally larger surface area and significant aspect ratio than their micro-scale counterparts, which promotes the development of mechanical and barrier properties. Nanocomposites are attracting considerable interest in food packaging because of these fascinating features. On the other hand, natural fibres are susceptible to microorganisms and their biodegradability is one of the most promising aspects of their incorporation in polymeric materials. Present review article explain about different categories of nanoclay and natural fibre based composite with particular regard to its applications as packaging materials and also gives an overview of the most recent advances and emerging new aspects of nanotechnology for development of hybrid composites for environmentally compatible food packaging materials.
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