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Carbon storage potential in natural fiber composites

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Abstract

The environmental performance of hemp based natural fiber mat thermoplastic (NMT) has been evaluated in this study by quantifying carbon storage potential and CO2 emissions and comparing the results with commercially available glass fiber composites. Non-woven mats of hemp fiber and polypropylene matrix were used to make NMT samples by film-stacking method without using any binder aid. The results showed that hemp based NMT have compatible or even better strength properties as compared to conventional flax based thermoplastics. A value of 63 MPa for flexural strength is achieved at 64% fiber content by weight. Similarly, impact energy values (84–154 J/m) are also promising. The carbon sequestration and storage by hemp crop through photosynthesis is estimated by quantifying dry biomass of fibers based on one metric ton of NMT. A value of 325 kg carbon per metric ton of hemp based composite is estimated which can be stored by the product during its useful life. An extra 22% carbon storage can be achieved by increasing the compression ratio by 13% while maintaining same flexural strength. Further, net carbon sequestration by industrial hemp crop is estimated as 0.67 ton/h/year, which is compatible to all USA urban trees and very close to naturally, regenerated forests. A comparative life cycle analysis focused on non-renewable energy consumption of natural and glass fiber composites shows that a net saving of 50 000 MJ (∼3 ton CO2 emissions) per ton of thermoplastic can be achieved by replacing 30% glass fiber reinforcement with 65% hemp fiber. It is further estimated that 3.07 million ton CO2 emissions (4.3% of total USA industrial emissions) and 1.19 million m3 crude oil (1.0% of total Canadian oil consumption) can be saved by substituting 50% fiber glass plastics with natural fiber composites in North American auto applications. However, to compete with glass fiber effectively, further research is needed to improve natural fiber processing, interfacial bonding and control moisture sensitivity in longer run.

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... VF has the potential to improve the mechanical properties of mortar and concrete, especially the toughness and post-cracking strength [21][22][23]. The capacity that the VF has for carbon sequestration is an important factor to be considered to slow the growth of CO 2 in the atmosphere [24]. Based on composites of polymeric matrices, composites reinforced by VF consume only 37% of the energy in their entire life cycle, when compared to a composite reinforced by glass fibers [24,25]. ...
... The capacity that the VF has for carbon sequestration is an important factor to be considered to slow the growth of CO 2 in the atmosphere [24]. Based on composites of polymeric matrices, composites reinforced by VF consume only 37% of the energy in their entire life cycle, when compared to a composite reinforced by glass fibers [24,25]. A similar reduction can be achieved for composites based on cementitious matrices [24]. ...
... Based on composites of polymeric matrices, composites reinforced by VF consume only 37% of the energy in their entire life cycle, when compared to a composite reinforced by glass fibers [24,25]. A similar reduction can be achieved for composites based on cementitious matrices [24]. ...
Article
Alkali-activated binders (AAB) are materials based mainly on silica, alumina, and/or calcium precursors, activated by an alkaline solution, and have mechanical properties equivalent to Portland cement-based matrices. However, their brittle behavior requires the use of reinforcements to make them suitable for dynamic or tensile load applications. Vegetable fibers (VF) could reinforce fragile construction materials, such as mortar and concrete, improving toughness and post-cracking strength. However, little is known about VF durability when used as a reinforcement of AAB. Thus, this work is a literature review regarding the use of VF as an AAB reinforcement, discussing the durability aspects of these fibers as well as future challenges for consideration of the composite. Mechanism of degradation of vegetable fibers in alkali-activated matrices based on sodium has been introduced. Furthermore, this review concluded that surface protection through direct treatments can be an important factor for the durability of vegetable fibers. The main effects of the degradation of composites observed were the reduction in flexural strength and the reduction of matrix/fiber adhesion.
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... Published LCAs, available for BCs, conclude that the addition of natural fibres to replace all or part of the synthetic fibres demonstrates a reduced EI for that component [13][14][15][16][17][18][19]. It has been reported that NFRPs consume around 63% less energy than glass fibre reinforced polymers (GFRPs) during their entire life cycle [19]. Whilst this provides a strong justification to consider selecting bio-based materials, there are other limitations that must be accounted for when replacing traditionally-used synthetic counterparts. ...
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Article
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... Since the 1970s, a growing concern about ecology and sustainable development, first highlighted by the United Nations Conference on the Human Environment in 1972, has drawn the attention of industries and researchers. Since then, fossil fuels such as petroleum, one of the most explored materials, have been appointed the main worldwide carbon dioxide emitter, a greenhouse gas (Pervaiz and Sain 2003). Even though, polymeric materials, obtained from petroleum, are still in use in several applications, such as in automotive, civil construction, and packaging industries, the major waste generators (Cholake et al. 2017;Geyer, Jambeck, and Law 2017;Passarini et al. 2012;Sapuay 2016). ...
... Among the well-known NFLs, the hemp fibers, extracted from the Cannabis sativa L. stalks, must be more explored by researchers from Materials Science and Engineering areas in an immediate future. Although they are one of the oldest crops used in several products, such as in clothes and ropes (Thyavihalli Girijappa et al. 2019), their application as reinforcement of polymeric matrices in place of the synthetic fiber is still in early stages commercially (Cholake et al. 2017;Geyer, Jambeck, and Law 2017;Passarini et al. 2012;Pervaiz and Sain 2003;Sapuay 2016;Yan, Kasal, and Huang 2016). Their potential performance was already evidenced in a few works, where they were used even in ballistic applications (Ribeiro et al. 2021). ...
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The constant concern about environmental issues has led to the growth of researches about eco-friendly materials. Among them, the natural lignocel-lulosic fibers have already presented their potential in place of petroleum-based synthetics. However, a relevant number of studies still have to deal with their disadvantages, such as the weak bond on the matrices for a composite performance and limited thermal performance. Thus, the present study analyzes a combination of alkaline treatment and graphene oxide coating in hemp fibers, an NLF applied in several products but with few investigations in engineering applications. The hemp fibers were thermally characterized with thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The GO-coating was evidenced by the Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy. Changes in crystallinity were presented by X-ray diffraction (XRD). It was observed an increase of about 4% to 11% of the crystallinity after the alkaline treatment. The thermal stability rose about 13°C in the 10 wt% NaOH-treated and GO-coated fibers, and a change of about 3.5°C was detected for the glass transition temperature. The GO-coating effect was also evidenced by changes in Raman spectra and FTIR curves and was visually detected in the scanning electron microscope (SEM). 摘要
... Natural fibres in polymer composite manufacturing could reduce the consumption of fossil fuels. It has been reported that a 50% replacement of glass fibre composites in North American auto applications with natural fibre composites could lead to a reduction in CO 2 emissions of up to 3.07 million tonnes, saving 1.19 million m 3 of crude oil [123] . Natural fibre-based composites play a critical role in the storage of carbon since they control the emission of carbon from natural fibres by reducing decay and burning of natural fibre [123] . ...
... It has been reported that a 50% replacement of glass fibre composites in North American auto applications with natural fibre composites could lead to a reduction in CO 2 emissions of up to 3.07 million tonnes, saving 1.19 million m 3 of crude oil [123] . Natural fibre-based composites play a critical role in the storage of carbon since they control the emission of carbon from natural fibres by reducing decay and burning of natural fibre [123] . However, this can only be achieved for a limited period, i.e. until the disposal of the composite material, and it cannot be adapted in all countries because of the application of varying disposal methods. ...
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Biocomposites being environmentally-friendly alternative to synthetic composites are gaining increasing demand for various applications. Hence, biocomposite development should be integrated within a circular economy (CE) model to ensure a sustainable production that is simultaneously innocuous towards the environment. This review presents an overview of the state-of-the-art technologies for the adoption of the CE concept in biocomposite development. The study outlined the properties, environmental and economic impacts of biocomposites. A critical review of the life-cycle assessment of biocomposite for evaluating greenhouse gas emissions and carbon footprints was conducted. In addition, the opportunities and challenges pertaining to the implementation of CE have been discussed in detail. Recycling and utilisation of bio-based constituents were identified as the critical factors in embracing CE. Therefore, the development of innovative recycling technologies and an enhanced use of novel biocomposite constituents could lead to a reduction in material waste and environmental footprints. This article is one of the first studies to review the circularity of biocomposites in detail that will stimulate further research in enhancing the sustainability of these polymeric materials.
... To reduce the material cost, weight and to provide sustainable solutions, natural fiber-reinforced composites have many attractive features, particularly beneficial in plastics, electronics, packaging [64], and automotive industry [65][66][67]. For consumer applications, the natural fiber reinforced hybrid composites are utilized for interior paneling, household tables, window panels, and chairs [67,68]. ...
Article
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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 along with their developing demand on the environmental sustainability of engineering materials. NFRPCs are widely applied in various engineering sustainable applications and this research field is continuously developing. However, the researchers faced numerous challenges to 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 matrices. Ecological and economic concerns are animating new research in the field of NFRPCs. Furthermore, considerable research was 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 fibers and glass fiber hybrid composites also gives good mechanical properties, As Individual fibers give good properties and it has been proved through research, hybrid composites also give good properties. From the last decade researchers focused on hybrid composites as well [4,5]. ...
Article
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Now a day’s researchers are working on various materials that are biodegradable in nature and eco friendly. In the field of engineering composite material use is increasing continuously. The Composite contains mainly Matrix and Fiber. Jute, Coir, Silk, Banana, Bamboo fibers are utilized to develop composites as it gives good strength. In recent studies, it has been observed that banana fiber showed good chemical and mechanical properties that can be used in various industries like textile and packaging industry as a raw material. The hybrid composite material can be used to produce various products that may helps farmer financially and have a good scope to create a new market for startups. In this proposed work, for preparing the composites epoxy is used as matrix and Banana fibers and coir fibers are used as reinforcement material. Laminate and specimens for testing have been fabricated by using continuous fibers. The banana and coir fibers have been treated with 5% NaOH solutions to remove lignin. The specimens have been prepared by varying coir percentages in laminate i.e 5 %,10 %, and 15 % and maintaining 10% banana fiber constant for all the specimens. The mechanical properties of specimen i.e.x tensile strength, flexural strength have been tested on Universal Testing Machine (UTM). The coir/banana hybrid composite with a weight fraction of 5% and 10% respectively shows maximum tensile strength i.e 13.06 Mpa. and Flexural strength of 32.33 Mpa.
... Pervaiz and collaborators have performed a similar study in the automotive sector, in this case replacing a PP part containing 30% glass fiber by the same PP with 65% of hemp fibers, obtaining a reduction of around 50,000 MJ per ton of composite. If the use of a vehicle is considered, further reductions in carbon dioxide emissions can be achieved, due to a 21% reduction of the weight of the part [73]. ...
Article
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This paper assesses the aspects related to sustainability of polymer composites, focusing on the two main components of a composite, the matrix and the reinforcement/filler. Most studies analyzed deals with the assessment of the composite performance, but not much attention has been paid to the life cycle assessment (LCA), biodegradation or recyclability of these materials, even in those papers containing the terms “sustainable” (or its derivate words), “green” or “eco”. Many papers claim about the sustainable or renewable character of natural fiber composites, although, again, analysis about recyclability, biodegradation or carbon footprint determination of these materials have not been studied in detail. More studies focusing on the assessment of these composites are needed in order to clarify their potential environmental benefits when compared to other types of composites, which include compounds not obtained from biological resources. LCA methodology has only been applied to some case studies, finding enhanced environmental behavior for natural fiber composites when compared to synthetic ones, also showing the potential benefits of using recycled carbon or glass fibers. Biodegradable composites are considered of lesser interest to recyclable ones, as they allow for a higher profitability of the resources. Finally, it is interesting to highlight the enormous potential of waste as raw material for composite production, both for the matrix and the filler/reinforcement; these have two main benefits: no resources are used for their growth (in the case of biological materials), and fewer residues need to be disposed.
... In addition, replacing synthetic fibers with natural fibers provides significant environmental benefits (Sumrith et al., 2020;Vinod et al., 2021). It was shown that replacing 50% of glass fiber reinforced composites with natural fiber reinforced composites in North American automobiles led to a saving of 3.07 million-tons of CO 2 emissions and 1.19 million m 3 of crude oil consumption (Pervaiz and Sain, 2003). The natural fibers' merits and demerits are described in Table 2. ...
Article
The Environmental concern and awareness around the globe have led to the development of sustainable bio composites which are derived from renewable resources. Biodegradable polymers and natural fibers derived from different renewable resources have played a vital role in the manufacture of bio composites. Poly lactic acid or polylactide (PLA) is one of the versatile aliphatic linear thermoplastic biodegradable polymers obtained from fully renewable sources such as wheat, corn, rice and sweet potato, and it has unique characteristics like renewable, sustainable, biocompatible and compostable. PLA has distinct advantages like low energy consumption and emission of low greenhouse gas while production of any products from it. In addition, it can be degraded in water and can also produce CO2 at the end of their life cycle. Even though it has some demerits such as low gas and water barrier, toughness is poor and it is hydrophilic in nature, which led to its wide use in commercial applications. To enhance its commercial applications, PLA was blended with various natural fibers in order to improves the thermal, water barrier, crystallization, mechanical, antimicrobial and degradability properties. Moreover, inclusion of natural fibers not only decreases the cost of PLA products but also helps in producing good competitive commercial products which are used in different industries. Hence, this review focuses on the synthesis and degradation of PLA, its applications in various sectors and manufacturing methods involved in PLA composites. Moreover, this review discusses about the different types of natural fibers and their influence on the unique properties of PLA based natural fiber reinforced composites. The overall aim of this paper is to provide a holistic idea about PLA based bio composites to academicians, industry personnel and researchers.
... Synthetic fibers such as glass, carbon, and aramid are preferred to use as reinforcement in polymer composites (Mohd Nurazzi et al. 2017). Besides, there are few disadvantages of synthetic fibers such as limited recycling process, non-biodegradable, emission of greenhouse gases during production (Pervaiz and Sain 2003). ...
Article
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The application of a sandwich structure made with composite facesheet and honeycomb core has increased rapidly due to high stiffness to weight ratio characteristics. There is a growing interest in using natural/synthetic hybrid composite to enhance the mechanical performance of natural fiber and reduce the environmental impact compared to synthetic materials. This study investigates the mechanical properties (tensile, edgewise compression, flexural) of the honeycomb sandwich structure with the hybrid composite facesheet, reinforced with different kenaf and glass fiber ratios. Non-hybrid kenaf and glass fiber composites were fabricated for comparison. The result showed that increasing the glass fiber ratio in a hybrid facesheet significantly improved the mechanical performance of the sandwich structure. Compared to the non-hybrid kenaf composite, the hybrid composite showed improved tensile and compression strength by up to 233% and 79%, respectively. The hybrid composite (glass/kenaf/glass) achieved 76% tensile modulus and 87% compression strength of glass fiber composite when the results were normalized. The specific flexural stiffness of the hybrid facesheet using glass fiber in the outer layer exhibited comparable performance by obtaining 89% flexural stiffness of non-hybrid glass composite sandwich structure.
... Jute fibers are characterized by moderate moisture retention, good insulation properties, and, because of their high lignin content (up to 20 %), are brittle, but strong (Bledzki et al., 2015). If compared to glass fibers, frequently used as reinforcement of thermoplastics, natural fibers are 35-40 % lighter (Pervaiz and Sain, 2003), offer fewer risks to health in both manufacture and use, and are non-abrasive, thus not damaging the equipment used in manufacturing processes (Kumar and Allamraju, 2019). However, they suffer from some drawbacks, such as moisture absorption, low thermal stability, and low compatibility with nonpolar polymer matrices due to their polar nature (Bourmaud et al., 2020;del P.F.C. Lima et al., 2020). ...
Article
This paper addresses the recycling of an industrial waste of jute (Corchoruscapsularis) and polypropylene fibers from Tapetes São Carlos carpet manufacturer conducted through the manufacture of composite materials and use of polypropylene (PP), a compatibilizer (C), and nano-calcium carbonate (N). The components were mixed in a co-rotational twin-screw extruder and dumbbell-shaped specimens were produced by injection molding. A masterbatch was previously processed for improving N dispersion in the polymer matrix. The composites were exposed to accelerated aging and tested by tensile and contact angle measurements, and evaluated by visual appearance before and after accelerated aging. The morphological evaluation was conducted by scanning electron microscopy (SEM). The processing techniques used provided composites with 50 wt.% waste, good N dispersion, no thermal or mechanical degradation of fibers, and better mechanical properties than pure PP. The presence of industrial waste led to a 135 % improvement in the elastic modulus of PP matrix and decreased deformation at break from 435 % to 5 %.N acted as mechanical reinforcement and decreased wettability. 18 % and 16 % improvements were achieved in the elastic modulus of the matrix when N was incorporated through the masterbatch and by direct extrusion, respectively. The composite processed after the manufacture of the masterbatch and with no compatibilizer showed a 186 % improvement in the elastic modulus of the matrix, lowest wettability, and best average performance under accelerated aging. Accelerated aging promotes a small reduction in stiffness, but a drastic dropping in the elongation of the materials. The composites can potentially be used in several commercial applications due to their properties and processing flexibility, which are relevant from both sustainable and economic viewpoints.
... In this context, the use of bio-based building materials becomes an unavoidable solution, as it allows us to respond to current environmental problems [4,5]. Among these bio-based materials, hemp concrete, which is a mixture of hemp shives and binder [6][7][8][9][10][11][12]. ...
Article
The aim of this paper is to analyse the impact of hemp concrete on the overall hygrothermal behaviour of the building when it used as an infill layer in the envelope of wood-frame structures. Three wall configurations were considered in different climates. Then, a hygrothermal co-simulation approach was used to integrate the model of coupled heat and moisture transfer through multilayered walls in a dynamic thermal simulation tool for the building. The material properties which constitute the input parameters for the model were determined experimentally, according to the hygrothermal state of the material. The results showed that hemp concrete significantly reduces the energy consumption of the building and has better insulation properties than the two conventional building materials: brick and aerated concrete. This is justified by the good hygrothermal properties of this bio-based material, especially its high thermal resistance of 3.08 K.m²/W compared to 0.88 K.m²/W of brick and 2.28 K.m²/W of aerated concrete. In addition, for the three climates considered, the thermal comfort of the hemp concrete envelope is significantly improved. This material also allows stabilisation of relative humidity levels in the ambient air by naturally regulating the hygrometry, to ensure better ambience. The study shows that hemp concrete has interesting hygrothermal properties. Thus, this material can be used massively in the construction field in order to meet the requirements of the current standards which aim to reduce the energy and environmental impacts of dwelling and office building.
... Its fibres can also be used to make concrete or composites (Schwarzova, Stevulova, and Melichar 2017). The annual carbon sequestration potential of industrial hemp plantation is approximately 0.67 t/ha (Pervaiz and Sain 2003) and the carbon content of hemp around 2 kgCO 2 /kg (Butkutė et al. 2015). While Jami, Rawtani, and Agraval (2016) suggest hemp concrete to be 'carbon negative technology', Pretot, Collet, and Garnier (2014) showed that in hemp concrete wall structures, the lime-based binder is accountable for the largest environmental impacts. ...
Article
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In order to reach carbon neutrality, GHG emissions from all sectors of society need to be strongly reduced. This especially applies to the construction sector. For those emissions that remain hard to reduce, removals or compensations are required. Such approaches can also be found within the built environment, but have not yet been systematically utilized. This paper presents a review of possible carbon storage technologies based on literature and professional experience. The existing technologies for storing carbon can be divided into 13 approaches. Some are already in use, many possess the potential to be scaled up, while some presently seem to only be theoretical. We propose typologies for different approaches, estimate their net carbon storage impact and maturity, and suggest a ranking based on their applicability, impact, and maturity. Our findings suggest that there is an underutilized potential for systematically accumulating atmospheric carbon in the built environment.
... (i) Reduced environmental impacts and CO 2 storage [73,93,100,90] through eco-design methods. However, using biobased constituents does not necessarily result in a reduction in environmental impact; a life cycle analysis must be performed. ...
Article
The last 80 years have seen significant changes in industrial technologies, with the development of composite materials being particularly striking. These were hardly present before the Second World War but were made possible by the availability of new polymers, fibre reinforcements and innovative manufacturing techniques. In parallel, the traditional flax farming practices for the textile industry have benefited from major improvements in seed selection, retting and fibre extraction methods. This aims of this paper are twofold; first to describe the early work to develop flax fibre reinforced composites and compare their mechanical properties with those of contemporary flax fibres. And second, to understand the impact of significant efforts made recently to improve flax fibre production. The simple substitution of synthetic fibres is no longer sufficient to justify their use; their environmental benefits must be demonstrated, through life cycle analyses to support sustainable societal choices, and these are also discussed.
... The aim of this study was to evaluate the performance of a new family of red mud/fly ash based geopolymer composites reinforced with different volume percentages of hemp fiber. Recently, hemp fiber has been receiving widespread attention since it shows rapid growth, a large degree of dry biomass production, and a high carbon storage potential [32]. ...
Article
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Novel hemp fiber reinforced geopolymer composites were fabricated. The matrix was a new geopolymer based on a mixture of red mud and fly ash. Chopped, randomly oriented hemp fibers were used as reinforcement. The mechanical properties of the geopolymer composite, such as diametral tensile (DTS) (or Brazilian tensile) strength and compressive strength (CS), were measured. The geopolymer composites reinforced with 9 vol.% and 3 vol.% hemp fiber yielded average DTS values of 5.5 MPa and average CS values of 40 MPa. Scanning electron microscopy (SEM) studies were carried out to evaluate the microstructure and fracture surfaces of the composites. The results indicated that the addition of hemp fiber is a promising approach to improve the mechanical strength as well as to modify the failure mechanism of the geopolymer, which changed from brittle to “pseudo- ductile.”
... Similarly, the use of these composite materials in the automobile industry also depicted positive effects on the environment reducing the emissions of GHG by 15 % [98]. If non-renewable energy is consumed for manufacture of glass fibre composites and hemp fibre, savings of approximately 3 ton of CO 2 can be achieved [99]. Substitution of mineral fertilizers with organic fertilizers during their cultivation can lower the carbon foot print to 650 kgCO 2 e/ton of natural fibre [93]. ...
Article
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One of the crowning glories of 20th century was the development of petroleum-based plastics. Eighty years later, with pioneering advances and series of breakthroughs in research and industrial innovations, plastics have become an integral part of our everyday life. While the applications of plastics are multifarious, their unrestricted disposal is causing damages to the ecosystem services and biodiversity. Furthermore, the plastic economy entirely relies on non-renewable, climate-changing petrochemical resources. A circular economy (CE), which aims to retain plastics at their highest value for a longest period of time in the system is one of the strategies to overcome these challenges. The present article discusses about strategies that can be employed to incorporate circularity and concepts of CE in plastics production systems. It emphasizes that although CE aims at design out waste, it needs to go a step ahead and also consider the impact of raw materials, the entire product value chain and end-of life options to achieve sustainability. It captures the emerging area of biodegradable low-carbon polymers from renewable resources with an emphasis on technical and environmental advantages that contribute to reduction in carbon footprints. Research done from a sustainability standpoint by considering CO2 emissions right from production stage to end-of-life are reviewed. Some challenges that need to be addressed for future work, the potential role of sustainability analysis in enhancing use of biopolymers are summarized. Furthermore, it sheds light on integrating a low-carbon economy with the CE to achieve a holistic and sustainable plastics production value chain.
... Pervaiz and Sain studied the carbon storage potential of hemp in natural fibre in composite with polypropylene matrix and 325 kg of carbon storage was estimated in the biomass of hemp fibres of metric ton at case of 65% of fibre content [3]. The LCA of hempcrete was carried out by Arrigoni and others [4]. ...
Article
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Hemp concrete is considered to be a carbon negative material. Hemp absorbs CO 2 during the growth and lime needs CO 2 for carbonation. The material, which has good thermal insulation properties, is used as a non-bearing wall material or plaster. For such use the hygrothermal properties of a material must be well known especially when indoor insulation is in focus. In the current study hemp concrete produced in two different ways was in focus and following the hygrothermal properties of hemp concrete as a building material were studied: water absorption (EN 1015-18), water vapour sorption (EN 12571), water vapour permeability (EN 12572) and thermal conductivity (EN 12667). The results of the study can be used in hygrotheramal calculations and modelling.
... Another feasible way to use hemp fibers is to prepare mats to be utilized in buildings with thermo acoustic insulation functions. Pervaiz and Sain (2003) studied mechanical characteristics and environmental performances of natural and glass fiber thermoplastics mats. Their results revealed that natural hemp fibers have higher potential as sustainable "sink'" for CO 2 and can be used to save non-renewable energy resources. ...
Article
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Rising human population has increased the utilization of available resources for food, clothes, medicine, and living space, thus menacing natural environment and mounting the gap between available resources, and the skills to meet human desires is necessary. Humans are satisfying their desires by depleting available natural resources. Therefore, multifunctional plants can contribute towards the livelihoods of people, to execute their life requirements without degrading natural resources. Thus, research on multipurpose industrial crops should be of high interest among scientists. Hemp, or industrial hemp, is gaining research interest because of its fastest growth and utilization in commercial products including textile, paper, medicine, food, animal feed, paint, biofuel, biodegradable plastic, and construction material. High biomass production and ability to grow under versatile conditions make hemp, a good candidate species for remediation of polluted soils also. Present review highlights the morphology, adaptability, nutritional constituents, textile use, and medicinal significance of industrial hemp. Moreover, its usage in environmental conservation, building material, and biofuel production has also been discussed.
... 24 Moreover, the production of flax composite material reinforcements produces much less CO 2 than synthetic fibres. 25,26 In fact, the CO 2 produced during the manufacturing of flax fibre reinforcements can be offset by the CO 2 absorbed during the growth of the flax plants. 27 ...
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With growing restrictions on the exploitation and trade of current stringed musical instruments fingerboard materials such as ebony and rosewood, for economical and ethical reasons, instrument makers are looking for alternative materials. The present work describes the development of a homogeneous 60% bio-based flax fibre composite material with physical properties similar to commonly used fingerboard woods. As a proof of concept, prototype guitar neck was built using the material, demonstrating its compatibility with existing guitar manufacturing techniques.
... 205,206 It has long been suspected that the replacement of glass fibre-reinforced polymers with natural fibres such as hemp fibres could lower CO 2 emissions and decrease crude oil consumption because natural fibres have outstanding mechanical properties along the fibre axis. 207 In a recent study, the use of jute fibres instead of glass fibres was studied for buggy bonnets. 208 This study revealed that the use of jute had moderate environmental benefits that were essentially due to weight savings and to the production stage. ...
Article
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Cellulose in particular and phytomass in general are at the heart of our food system. They are also a central energy vector and a vital source of materials. In this article, a multiscale approach to the complex issue of lignocellulose sustainability is developed. Global thermodynamic concepts help to place current biomass exploitation in a global energetic context. In particular, the notion of entropy appears pivotal to understand energy and material fluxes at the scale of the planet and the limits of biomass production. Entropy is, however, best described at the microscopic scale, despite its large-scale consequences. Recent advances in entropy-driven colloid assembly parallel nature's choices and lignocellulose assembly at the nanometric scale. The functional concept of exergy is then developed and a few examples of its concrete use in photosynthesis and biorefinery research are given. In a subsequent part, an evaluation of the relative importance of biomass is performed with respect to non-renewable materials. This discussion helps to explain the interdependence of resources, including ores and fossil fuels. This interdependence has important consequences for current and future biomass uses. Some of these dependences are then quantitatively discussed using life cycle analysis (LCA) results from the literature. These results are of importance to different technological fields such as paper, biobased insulation, construction wood, information and communication technologies, and biobased textiles. A conclusion is then drawn that exposes the research tracks that are the most likely to be sustainable, including self-assembly, exergetically favourable options and low tech solutions.
... Hemp binds CO 2 from the atmosphere in the photosynthesis process in the growth phase: dry hemp contains approx. 50% carbon [30], which means that 1 t sequestrates approx. 1.8 t of CO 2 . ...
Article
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The present paper presents results of a study on hemp-lime composite – a novel building material which is gaining attention thanks to its pro-ecological values, as well as interesting hygrothermal characteristics. The thermal conductivity and vapour permeability tests were performed on composites which varied in terms of composition and density as a result of use of various binders, different proportions of ingredients in a mixture and different compaction level during manufacturing with the use of the tamping method. The results obtained, indicating low thermal conductivity and very high vapor permeability, were tabulated with results of compressive strength obtained in the previous study on the same types of composites. The conclusions emphasise supreme importance of apparent density on properties of material, rather than binder composition – which exerts a significant effect only on compressive strength. The results of the performed tests were applied for determination of external walls’ construction, which were subjected to analysis of risk of interstitial water vapor condensation according to Glaser method. For locations in all Polish climatic zones, no condensation or only a small amount thereof, in which case it does not accumulate in subsequent years, was found.
... Differences in the consumption of plastic bags, electrical energy, and lubricating oil/grease are the direct major factors in this study. Composites made from natural fibers on average can reduce energy consumption by 60% per ton compared to glass fiber composites according to Pervaiz and Sain [72]. This study also showed the production and shipping of one truckload of wood flour consumed lesser NRE sources and more RE sources compared to the one truckload of wood pellets. ...
Article
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This study is expanding the previous studies that were focused on the material properties and transportation costs of the two alternative feedstocks for manufacturing wood-plastic composites (WPCs): wood flour and pellets. Besides the material properties and cost analysis, life-cycle assessment (LCA) is equally important to assess the environmental impacts of these two alternative wood feedstocks to manufacture WPCs and gain the knowledge of influences from the manufacturing and transportation processes. The main goal of this study was to compare the environmental impacts from the production and transportation of wood flour and pellets utilized in WPC manufacture. The environmental impacts on air, water, soil and human health, as well as the cumulated energy consumption for one tonne and one truckload of the two wood feedstocks were compared. The case-study was based on a commercial wood pellet manufacturer in the state of Maine (ME). The cradle-to-gate approach was considered including the processing of mill residues, manufacturing of the two feedstocks and transporting them to commercial WPC manufacturers. LCA analysis showed that transportation of both feedstocks had the highest impact on the environment as opposed to the inputs associated with production. The global warming potential (GWP) from one tonne production and shipment of wood flour was higher by 8% compared to the pellets. One tonne production and shipment of wood pellets appears more environmentally friendly. Normalization results of one truck load of wood flour (22 tonnes) and pellets (30 tonnes) showed similar environmental impacts. Based on this study, from an environmental perspective, it is inferred that besides use as bio-fuels, wood pellets could be a better alternative feedstock for the manufacture of WPCs.
... The carbon sequestration rate of fibre-based hemp crops can surpass both urban and forest tree plantations. However, the main solution in maintaining good quality and better yield of hemp is 'crop rotation' [95]. According to [57], biomass provides a long-term solution to Ireland's energy needs while also addressing greenhouse gas mitigation in the agriculture sector. ...
Article
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There may be unrecognised environmental and economic benefits in cultivating industrial hemp for CO2 sequestration in Ireland. By using a Systems Thinking approach, this study aims to answer how industrial hemp, which can sequester between 10 to 22 million Mt CO2 per hectare, has been helpful towards carbon sequestration efforts. A mixed-methods design combining qualitative and quantitative secondary material is used to inform Behaviour over Time Graphs (BoTGs) to illustrate the data from 2017 to 2021. In 2019 the total CO2 emissions from agriculture was 21,151.24 million Mt, and the total land cultivated with hemp was 547 hectares which represented 0.0079% of total land use and 0.0123% of agricultural land use. Based on a sequestration rate of between 10 and 22 million Mt of CO2, industrial hemp had the potential to sequester between 5470 Mt and 24,068 million Mt of CO2, this represents nearly quarter to potentially all the CO2 from agriculture and equates to a carbon tax equivalent of between €109,400 and €481,360 for that year. The total amount of CO2 sequestrated between 2017 and 2021 was between 14,660 million Mt and 64,504 million Mt of CO2. This represents an estimated contribution in carbon tax equivalent of between €348,805 and €1,534,742, respectively.
... Hemp needs large amounts of carbon dioxide to grow. One ton of dry matter in hemp yield can store 1000-2900 kg of CO 2 [1,[5][6][7]. The straw as raw material has therefore a highly negative carbon footprint. ...
Article
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The article presents the results of studies concerning raw hemp shives obtained from the Polish crop of industrial hemp as a loose-fill thermal insulation material. The study focuses mainly on the measurements of the pore size distribution, thermal conductivity and air permeability of material. An increase in the value of the thermal conductivity coefficient (0.049–0.052 W/(m·K)) was demonstrated with an increase in the bulk density. The porosity of the individual pieces of shives is 78.7% and the predominant number of pores is in the diameter range of 0.9–3 μm. The paper also presents an example of the use of the tested material as thermal insulation of the wooden frame wall. The heat flow analysis was performed in various wall variants (insulation thickness: 100, 200 and 300 mm and pressure difference 0, 5, 10 and 15 Pa). A clear influence of the variables on the temperature distribution was observed.
... Natural mposites also gives good Individual fibers give good proved through research, hybrid composites also give good properties. From the last decade composites as well [4,5]. ...
Research
Now a day's researchers are working on various materials that are biodegradable in nature friendly. In the field of engineering, composite is increasing continuously. The Composite contains mainly Matrix and Fiber. Jute, Coir, Silk, Banana, Bamboo fibers are utilized to develop composites as it gives good strength. In recent studies, it has been observed that banana fiber showed good chemical and mechanical properties that can be used in various industries like textile and packaging industry as a raw material. The hybrid composite material can be used to produce various products that may helps farmer financially and have a good scope to create a new market for startups. In this proposed work, for preparing the composites epoxy is used as matrix and Banana fibers and coir fibers are used as reinforcement Laminate and specimens for testing have been fabricated by using continuous fibers. The banana and coir have been treated with 5% NaOH solutions lignin. The specimens have been prepared by varying coir percentages in laminate i.e 5 %,10 %, maintaining 10% banana fiber constant specimens. The mechanical properties tensile strength, flexural strength have Universal Testing Machine (UTM). The hybrid composite with a weight fraction of 5% and 10% respectively shows maximum tensile strength Mpa. and Flexural strength of 32.33 Mpa.
... Flax is the natural fiber that has shown outstanding potential to replace synthetic reinforcement materials such as glass fibers. The important properties of flax include its low cost per weight, low cost per length of minimum fiber material required to resist 100 kN, low production energy consumption, and high tensile strength [6][7][8]. The increasing use of flax composites in the design of structural parts necessitates the separate assemble of various sections. ...
Article
The influence of conventional drilling (CD) and abrasive water jet (AWJ) machining on the mechanical behavior of hybrid carbon/flax composites was investigated. The specimens were manufactured using woven carbon fiber (C) and unidirectional flax fiber (F) in three configurations: unidirectional [0-90C2/0F6]S, cross-ply [0-90C2/(0/90)F6]S, and angle-ply [0-90C2/(±45)F6]S laminates. The examination of the hole surface revealed severe damage in the form of peel-up, push-out, and secondary delamination of AWJ machined holes, and only push-out delamination at the exit side of the CD drilled hole. A delamination factor was developed to quantify the delamination at the hole surface. The specimens were subjected to quasi-static load-unload tensile tests to assess their damage response and surface fracture. Unidirectional and angle-ply specimens drilled with AWJ accumulated a higher damage compared to CD specimens. This correlates with the delamination factor, indicating that the delamination at the entry and exit of the hole and secondary delamination greatly affect the damage evolution of the laminates.
... Natural mposites also gives good Individual fibers give good proved through research, hybrid composites also give good properties. From the last decade composites as well [4,5]. ...
Article
Full-text available
Now a day's researchers are working on various materials that are biodegradable in nature friendly. In the field of engineering, composite is increasing continuously. The Composite contains mainly Matrix and Fiber. Jute, Coir, Silk, Banana, Bamboo fibers are utilized to develop composites as it gives good strength. In recent studies, it has been observed that banana fiber showed good chemical and mechanical properties that can be used in various industries like textile and packaging industry as a raw material. The hybrid composite material can be used to produce various products that may helps farmer financially and have a good scope to create a new market for startups. In this proposed work, for preparing the composites epoxy is used as matrix and Banana fibers and coir fibers are used as reinforcement Laminate and specimens for testing have been fabricated by using continuous fibers. The banana and coir have been treated with 5% NaOH solutions lignin. The specimens have been prepared by varying coir percentages in laminate i.e 5 %,10 %, maintaining 10% banana fiber constant specimens. The mechanical properties tensile strength, flexural strength have Universal Testing Machine (UTM). The hybrid composite with a weight fraction of 5% and 10% respectively shows maximum tensile strength Mpa. and Flexural strength of 32.33 Mpa.
... An amount of 1.84 kg of CO2 per kg of dry hemp is stoichiometrically calculated to be sequestered via photosynthesis, considering that a kilogram of hemp stems contains 0.5 kg of carbon (Pervaiz and Sain, 2003). Since the uptake of CO2 by the plant is a strictly physical quantity, this flow is massallocated. ...
Conference Paper
Hempcrete is a natural building material obtained mixing hemp shives (i.e., the woody core of the hemp plant) with a lime-based binder and water. Hempcrete as construction material is gaining increasing interest as the EU aims to achieve net zero emissions by 2050. This material has, in fact, the ability to uptake carbon dioxide from air (i.e., via carbonation) and to store carbon for long time. The goal of the present work is to deeper analyze the environmental profile of hempcrete, in order to assess its potentials in reducing emissions of construction sector. Specifically, Life Cycle Assessment (LCA) of a non-load-bearing wall made of hempcrete blocks is carried on. The analysis encompasses the whole life cycle from the extraction of raw materials to the end of the service life. The analyzed blocks are produced by an Italian company. Only aerial lime is used as binder, microorganisms are added to the blocks to accelerate carbonation. The impact on climate change is assessed through the GWP 100 method proposed by IPCC. Preliminary results reveal a nearly neutral carbon budget.
Article
The development of a thermal form-active composite, based on Oak-Paulownia-Flax materials is presented, including new knowledge and methods for material-driven responsive envelopes in an architectural scale. The study investigates, examines, and propose an experimental wood-textile structure that directly address questions on reducing embodied and operational energy in the built environment by a novel use of CO2 absorbing regenerative materials. Thermal-active wood bi-layers are combined with organic textiles to create a responsive and modular envelope element. This element is nested into a new lightweight load bearing BoxBeam-Zollinger structure, with flax textile surface connections. Both form active composite and load bearing structure is inspired by skin-on-frame material-structural concepts observed in vernacular boat cultures. The structure alone is measured to 1 kg/m2, with a combined weight of the entire responsive envelope of 4.3 kg/m2. The studies are based on experimental prototypes and computational simulation studies before a full-scale demonstrator project is constructed to test and disseminate the knowledge and methods for designing material efficient, thermally active architectural envelopes.
Article
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Substitution of flax fibres for synthetic fibres in fibre-reinforced polymer (FRP) composites has recently been considered an effective step towards achieving more sustainable industrial practices, enabled by the fact that flax fibre has mechanical properties that are comparable to that for glass fibre. Three flax FRP (FFRP) pipes with the same length and internal diameter but having variations in the wall thickness were manufactured. The pipes had a fixed end and had a free end and were tested for 54 harmonic excitations with various dynamic properties when the pipes were buried or were unburied. The effect of shaking frequency, peak ground acceleration, wall thickness and soil cover on the dynamic response of the FFRP pipes was investigated. Finite element modelling was also used to verify the experimental results and to study the pipe behaviour when subjected to harmonic excitations. Results showed that while for the unburied pipes, the maximum pipe strain occurred at the cross-section next to the fixed end; for buried pipes, the largest strain developed at various cross-sections along the pipe length.
Article
Hemp, or industrial cannabis, is on a massively growing trend as a natural additive for high-performance bio-based building materials. However, thousands of stems from vernacular cannabis cultivation in developing countries, such as Morocco, are overlooked and regarded as biomass waste used for rural household purposes. The objective of this paper is to assess the potential use of Moroccan cannabis fibers in the manufacture of local bio-insulating plasterboards. Firstly, the study focuses on the mineralogical, morphological, and chemical characterization of used fibers using X-ray diffraction (XRD), thermogavimetric analysis (TGA), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). Secondly, the impact of fiber addition on the thermal performance of plaster was experimentally studied using Hot Disk and flash methods. For this study, one hundred local fibro-plasterboards were developed by adding Moroccan Hemp Fibers (MHFs) to local plaster at different weight replacement ratios: 0, 2, 4, and 6% in order to evaluate the effect of fiber content on the thermal insulation quality of plaster and the variation of the thermal capacity of developed bio-composites. The experimental tests demonstrate the effectiveness of Moroccan hemp stems in improving the thermal transport properties of plaster and making it more thermally efficient. The incorporation of 6% in weight of MHFs in plaster matrix considerably reduced the density, enhanced the thermal insulation and slowed the heat transfer rate respectively by 24.5%, 31.3% and 8.5% when compared to plaster without fibers. The addition of 2% in weight of MHFs showed the best results in terms of thermal heat capacity. Finally, to evaluate the energy performance of developed plasterboards at building scale, annual simulations using EnergyPlus for a residential building located in two different semi-arid climates of Morocco were carried out. The results indicate that buildings with 40 mm Moroccan hemp plasterboard (MHP) have a considerable potential to reduce the energy consumption of buildings and provide passive thermal comfort for occupants, especially during summer periods. Therefore, non-industrial hemp is a good candidate for the development of local lightweight low-environmental impact (LLL) construction materials with contributions for building energy efficiency.
Chapter
Due to the alarming rise in environmental regulations and ecological threats, research on natural fiber-based biodegradable polymer composites has burgeoned. One such polymer which has received a plethora of attention in recent years is Poly-Lactic Acid (PLA). Natural fibers possess distinct physical, chemical, and mechanical properties. In addition, it is recyclable, less expensive, and easily available. However, natural fibers have some drawbacks like moisture absorption, subsequent swelling, poor chemical resistance, and poor interfacial interactions with polymer matrices. These shortcomings can be overcome through surface modification techniques which include the usage of plasma technology and chemical agents such as sodium chloride, silane, stearic acid, etc. This paper presents a review of the mechanical properties of PLA based natural fiber composites. This review also demonstrates the influence of fiber surface treatment and manufacturing methods on the properties of PLA composites.
Article
Energy shortages and climate change call for the development of clean and sustainable energy. The development of green materials for clean energy storage and conversion is conducive to promoting the widespread use of clean energy. Conjugated microporous polymers (CMPs) have been synthesized with various structures and properties, which offer designability for the molecular structures and nanopores of conjugated skeletons. The research of CMPs in clean energy technologies is significant for the improvement of CMP-based materials and their application in energy and environmental engineering. CMPs have shown great potential for challenging energy and environmental issues such as gas adsorption, photocatalysis, solar energy conversion, and electrical energy storage and conversion. This review aims to summarize the advances of synthesis and design on CMPs, computer simulations on CMPs, and the applications of CMPs in the clean energy technologies including hydrogen evolution and storage, the adsorption and conversion of carbon dioxide, rechargeable batteries, supercapacitors, fuel cells, and photovoltaic cells. We also propose the challenges and potential chances of the synthesis and the clean energy applications of CMPs.
Article
This paper evaluates two types of concrete with hemp fibres as natural aggregates prepared with inorganic binders, based on reactions (Si-Na) and (Si-Ca). It also was tested two states of conservation of the hemp: 1) fresh and 2) preserved in moist conditions for six months. The results indicate that the changes induced by wet preservation, above all the increase in the percentage of cellulose, improve the mechanical properties of the concretes and is equivalent to other pretreatments conducted to improve the conditions of the hemp fibres confirmed by performing compositional, mineralogical and physical studies of the raw materials and the concretes. The dosages used in this study provided high quality concretes in comparison with other studies with similar dosages.
Article
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This research is aimed at developing the sandwich structure with a hybrid composite facesheet and investigate its mechanical properties (tensile, edgewise compression, and flexural). The combination of renewable and synthetic materials appears to reduce the weight, cost, and environmental impact compared to pure synthetic materials. The hybrid composite facesheets were fabricated with different ratios and stacking sequence of flax and glass fibers. The nonhybrid flax and glass composite facesheet sandwich structures were fabricated for comparison. The overall mechanical performance of the sandwich structures was improved by increasing the glass fiber ratio in the hybrid composites. The experimental tensile properties of the hybrid facesheet and the edgewise compression strength and ultimate flexural facing stress of the hybrid composites sandwich structures were achieved higher when the results were normalized to the same fiber volume fraction of glass composite. The hybrid composite sandwich structure showed improved compression and flexural facing stress up to 68% and 75%, respectively, compared to nonhybrid flax composites. The hybrid composite using glass in the outer layer achieved the similar flexural stiffness of the nonhybrid glass composite with only a 6% higher thickness than the glass composite sandwich structure.
Article
Development of Composite materials has made a huge impact in the history of the materials. Current Engineering market chooses composite materials instead of traditional materials, inspired by the superior properties exhibited by the composite materials. To reap the benefits, in concern with the environmental scenario, Natural fibers, instead of synthetic fibers are reinforced to the polymer matrix. As the Engineering sector is forced to reduce the Carbon dioxide emissions, in order to reduce the effect of Global warming, Manufacturers place natural fibers for Synthetic fibers to yield Green products, thereby reducing the effect of global warming. Strict norms controlling the synthetic fiber employment in the market, has given way for the Researchers to develop Composite natural fibers and bio degradable with better properties to that of synthetics. Fields such as Automobiles, Building construction started leaning over Composite platform for their promising features. Even though these Natural fibers possess advantageous features like easy availability, Reusable nature, easily degradable, etc., they do possess disadvantageous features. As these natural fibers do exhibit superior nature in Mechanical properties, Properties such as adhesiveness, wetting ability, etc., put them down the line of synthetic fibers. These inferior qualities of the natural fibers can be much reduced by the usage of two different fibers in one reinforcement. This technique is known as hybridization. Chemical treatment of Hybrid fibers does yield better properties. In this paper, Mechanical & Thermal properties of Coir - Kenaf fiber reinforced epoxy composites are studied to assess the influence of Fiber treatment. The specimen fibers were tested both for treated and Untreated condition. Treated specimen exhibits better Mechanical properties than the untreated one. It is found that the thermal conductivity of treated is more than the untreated hybrid composites.
Article
Hybrid composites occupying the area of standard materials by satisfying the necessities of various sectors like part industries, automobile industries, ship building and numerous bio-medical sectors. the most reason to substitute standard materials is that the hybrid composites giving same or additional needed properties with less weight and value than standard materials and most output in minimal consumption with higher lifespan to seek out the economical suggests that of utilizing the technology for various applications. Mats were fancied and stratified up with rosin matrix. The laminate is factory-made exploitation hand lay-up technique followed by compression moulding. Critical properties of the fancied material like flexure, enduringness, square measure through an experiment all over and results square measure recorded. The aim of the current analysis work was experimental investigation to judge numerous mechanical properties of hybrid fiber compound composite (E-glass fiber and epoxy, Banana fibres) at totally different weight percentages with epoxy. The properties of E-glass fiber and epoxy, Banana, fibres were found to be sensible large to be used as reinforcement in composite materials. The results of the experiments were per shaped on one hundred kN servo hydraulic universal testing machine (UTM) (50% E-glass, 100% of banana fiber and therefore the four-hundredth of epoxy resin) will study associate optimum results of the composite. In water absorption take a look at C-1(20% E-glass, four-hundredth of banana fiber and therefore the four-hundredth of epoxy resin) will observe the absorption of water. and at last experimental study the water absorption depends on amount of banana fiber.
Article
Wood biomass is an alternative for fossil fuels to produce bioenergy, due to its low cost, renewability and environmental friendliness. In order to use biomass as an energy source, understanding its thermal degradation behavior is highly recommended. This work focuses on the thermal degradation of wood fibers belonging to different species (Pinus elliotti (PIE), Eucalyptus grandis (EUG) and Mezilaurus itauba (ITA)), commonly used by the Brazilian lumber industry. The prediction of their degradation kinetics and overall thermal behavior was performed based on the most common theoretical data using the F-test statistical tool. The most probable degradation mechanism was found to be autocatalytic for all the wood fibers tested, with three different degradation steps. The results obtained were in accordance with the findings recently reported in the literature using other fitting methods. It was found that cellulose is the major contributor to Arrhenius parameters, while hemicelluloses – to reaction order.
Article
Sandwich structures made of glass-reinforced composite facesheet (FS) and honeycomb core are using in many load-carrying applications. This study aims to reduce the dependency on synthetic materials in the composite FS of sandwich structure. Recently, there has been rapid growth in research and innovation in the hybrid composite to achieve the comparable performance of synthetic materials and reduce the cost, weight, and environmental impact. In the present research, the mechanical properties (tensile, axial compression, and flexural) with flax/glass hybrid composite FS sandwich structure were investigated. The hybrid FS was fabricated with different ratios of glass and alkali-treated flax fiber. The sandwich structure with non-hybrid alkali-treated flax and glass composites FS were fabricated for comparison purposes. The overall results showed the potential of using hybrid reinforcement to improve the structural performance compared to non-hybrid flax composite and revealed the promising and comparable structural performance compared with glass composite. The hybrid composite FS by replacing 25% glass by weight with flax fiber achieved 96% axial compression strength and 92% flexural facing stress of glass composite. The H2 hybrid FS using glass in the outer showed only 6% lower flexural stiffness than non-hybrid glass composite when the normalized flexural stiffness results were compared.
Article
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Flax fibre has recently been found to have the potential to replace synthetic fibres in fibre reinforced polymer composites, and in the presented study, flax fabric-reinforced epoxy (FFRE) is introduced as a new material for structural tube manufacture. Four-point loading experiments were conducted on twelve FFRE specimens with the same span-to-diameter ratio, but a varying number of fabric layers, to establish the effect of the number of fabric layers on flexural strength, deformation characteristics, energy absorption capability, axial and circumferential strains, as well as the tube failure mechanism. Cross-sectional deformation (i.e. squashing of the cross-section along the tube span) was observed to be the dominant deformation mode associated with tube flexural response. The experimental results obtained were compared to the analytical expressions available in the literature for tubes placed between rigid plates parallel to tube axial axis and subjected to lateral compression (squashing), and good correlation was found between the experimental and predicted results.
Article
Purpose The study aims to investigate the influence of fabric hybridization, stacking sequences and matrix materials on the tensile strength and damping behavior of jute/carbon reinforced hybrid composites. Design/methodology/approach The hybrid composites were fabricated with different sequences of fabric plies in epoxy and polyester matrix using a hand layup technique. The tensile and vibration characteristics were evaluated on the hybrid laminated composite models using finite element analysis (FEA), and the results were validated experimentally according to ASTM standards. The surface morphology of the fractured specimens was studied using the scanning electron microscope. Findings The experimental results revealed that the position of jute layers in the hybrid composites has a significant influence on the tensile strength and damping behavior. The hybrid composite with jute fiber at the surface sides and carbon fibers at the middle exhibited higher tensile strength with superior damping properties. Further, it is found that the experimental results are in good coherence with the FEA results. Originality/value The less weight and low-cost hybrid composites were fabricated by incorporating the jute and carbon fabrics in interply configurations. The influences of fabric hybridization, stacking arrangements and matrix materials on the tensile and vibration behavior of jute/carbon hybrid composites have been numerically evaluated and the results were experimentally validated.
Chapter
The syngas conversion including hydroformylation of olefins and carbonylation represents some of the significant applications of catalytic materials and process in chemical industry. These reactions possess a diversity of mechanism, involve various catalytic materials, and offer options for continuous investigation. This chapter will focus on the relevant achievement of the research team of Catalysis in Syngas Conversion and Fine Chemicals in Dalian Institute of Chemical Physics, Chinese Academy of Sciences since 2000s. Specific contents will include the development of (i) heterogeneous hydroformylation of olefins; (ii) carboxylation of alcohols using single‐Rh‐site catalyst based on porous organic polymers (POPs); and (iii) other catalytic reactions using POP multifunctional materials. The innovative work of the single‐metal‐site catalyst based on POP material is highlighted.
Article
Understanding the mechanisms of CO2 hydrogenation on a specific catalyst is of profound significance for developing the high-efficient catalytic materials. Herein, first-principles calculation is performed to research the mechanisms of methanol synthesis from CO2 hydrogenation on tungsten (W)-doped Rh(111) catalyst. The optimal adsorption site, geometric parameters, and adsorption energy of each species are determined. The analysis of electronic structure reveals that CO2* is greatly activated on the W-doped Rh(111) surface due to the charge transfer and obvious orbital hybridization between them. Then, a descriptor is defined to preliminarily predict the reaction thermodynamics. Furthermore, the optimal reaction mechanism is determined by comparing the activation barriers and reaction energies of all elementary reactions. Compared with Rh(111), it can be found that the doping of W has a great hindrance to the elementary reactions in the RWGS and trans-COOH pathways, while the elementary reactions of the HCOO pathway are less affected. The optimal hydrogenation route on the W-doped Rh(111) surface is the HCOO pathway followed by CO2* → HCOO* → HCOOH* → H2COOH* → H2CO* → CH3O* → CH3OH*. The analysis of Mulliken charge shows that after the doping of W atoms, the modified electronic structure of Rh(111) is conducive to the conversion of CO2 and the generation of CH3OH.
Article
This research designed to contribute to reduce the environmental impacts through the preparation of composites with recyclable materials to be used in different applications. To this end, composites have been developed based on jute recovered from packaging bags and polypropylene (PP) reclaimed from scraps obtained from the manufacture of PP yarns. The developed composites were then characterized. First of all, the optimum mass fraction was determined in order to achieve good mechanical performance. Several mass fractions (30%, 40%, 45%, 50%, 60%, and 70%) were experimented to find that the best characteristics were those of the biocomposite with 40% reinforcement (σ = 39.07 MPa, E = 4.60 GPa). With this ratio, jute–PP biocomposites were further developed with different jute architectures (Satin, Serge 2 × 2, Taffeta). A structural study of the different jute fabric wastes was carried out to confirm whether they are suitable for use with a thermoplastic matrix (i.e., at a processing temperature of ≥200°C). Tensile and bending tests were carried out on these composites to find out the effect of the weave structure of the reinforcement.
Article
This paper presents an experimental study of the fatigue behaviour of non-hybrid and hybrid twill flax and glass fabric-reinforced epoxy laminates. To this end, several plates of these composite materials were elaborated by the vacuum infusion process and three hybrid configurations were chosen. Specimens of these composite materials were subjected to tensile fatigue tests coupled with Acoustic Emission (AE) recording by considering two frequencies of 5 and 10 Hz with a loading level of 65%. The results from fatigue tests are deeply analysed to evaluate the fatigue loading effect on the stiffness degradation, hysteresis loops and damping ratio of the studied non-hybrid and hybrid composites. The obtained results show that the flax-glass hybridization improves the fatigue behaviour of the glass-epoxy laminate. In particular, the replacement of two internal glass layers with two flax ones reduces the loss of maximum stress by ∼13% and enhances the damping property by ∼60% at 10 Hz compared with the glass-epoxy laminate. On the other hand, the AE analysis allows identifying three classes of the recorded acoustic signals in all materials, which are attributed to the main damage mechanisms based on SEM observations.
Chapter
This study presents the first results of a research project aimed at creating prefabricated panels that consist of hemp blocks, to be used for closures and vertical partitions within load-bearing frames. With the study of the wall design, we wanted to provide high safety performance, as especially relevant for areas with high seismic risk (such as Italy), through the use of non-fragile products. The use of hemp blocks for prefabricated walls will also allow the development of strategies to: (i) reduce construction times; (ii) reduce decommissioning of buildings; and (iii) promote the use of sustainable construction products. Life-cycle assessment of hemp blocks (Canaplock) was also carried out. This study considers the ecological, economic, and social benefits of hemp, and transfers these to this new application. A comparison of the product conceived with similar products already on the market is developed, in particular for those with prefabricated straw and wooden panels. This study is the result of a collaboration between the world of research and the production sector, as it forms part of an industrial Doctorate. The results of this study will have an application outlet, as they will support the Canaplock manufacturer in the promotion and dissemination of the use of hemp-based products according to the criterion of sustainable development, especially as these can provide real benefits for the environment and the user.
Article
Fiber reinforced composites represent an alternative to traditional techniques for strengthening and retrofitting masonry structures. Within the growing environmental awareness, the development of composite materials to replace conventional synthetic fibers and polymeric matrices has become a crucial issue. In this paper, a novel sustainable composite material consisting in hemp fibers and a natural matrix made of a mix of ground clay bricks and organic binder is proposed. Experimental tests are carried out in order to estimate the mechanical characteristics of the single composite components. The structural performance of polycentric masonry arches strengthened at the extrados first with only natural matrix and then with the bio-composite material (i.e. hemp fibers and biodegradable matrix) is investigated. Single point vertical load tests and tilt tests are carried out in order to assess the effectiveness of the strengthening by comparing the results with those obtained with unstrengthened masonry arches.
Article
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The fabrication of polypropylene composites using various types of reinforcements to improve the mechanical properties has received much attention in recent years. In this paper, enhancing the mechanical properties of polypropylene composites by adding different classes of natural and synthetic particle and fiber reinforcements were reviewed. Accordingly, it was found that the fabrication of polypropylene composites leads to an increase either in the strength of samples and corresponding mechanical properties. Moreover, surface modification and processing reinforcements, especially natural fibers via chemical and physical methods were studied. The results show an increase in the adhesion of reinforcements surface inside the polypropylene, which results in strength enhancement and improving the mechanical properties of polypropylene composites. The evidence from this study points towards the idea that the increased use of modified natural fibers in polylropylene composites and those natural or synthetic reinforcements which form hybrid composites provide promising research topics in the future.
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Based on field data from 10 USA cities and national urban tree cover data, it is estimated that urban trees in the coterminous USA currently store 700 million tonnes of carbon ($14,300 million value) with a gross carbon sequestration rate of 22.8 million tC/yr ($460 million/year). Carbon storage within cities ranges from 1.2 million tC in New York, NY, to 19,300 tC in Jersey City, NJ. Regions with the greatest proportion of urban land are the Northeast (8.5%) and the southeast (7.1%). Urban forests in the north central, northeast, south central and southeast regions of the USA store and sequester the most carbon, with average carbon storage per hectare greatest in southeast, north central, northeast and Pacific northwest regions, respectively. The national average urban forest carbon storage density is 25.1 tC/ha, compared with 53.5 tC/ha in forest stands. These data can be used to help assess the actual and potential role of urban forests in reducing atmospheric carbon dioxide, a dominant greenhouse gas.
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A single agro-based fiber is a three dimensional, biopolymer composite com- posed mainly of cellulose, hemicelluloses, and lignin with minor amounts of free sugars, starch, protein, extractives, and inorganics. The performance of a given fiber used in a given application depends on several factors including chemical compo- sition, physical properties, the interaction of a fiber within the composite matrix, and how that fiber or fiber/matrix performs under a given set of environmental conditions. In order to expand the use of agro-fibers for composites, it is essential that information is available on fiber characteristics and the factors which effect performance of that fiber. In order to do this, it is necessary to develop a detailed data base of chemical and physical properties of the vast variety of natural fibers that are potentially available in the world. It is also necessary to understand the factors which effect the performance of a given fiber in a given application. This chapter will deal with the chemical and physical properties of agro-fibers and factors which effect fiber properties.
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Thermoplastic composites based on flax fibres and a polypropylene (PP) matrix were manufactured using (i) a film-stacking method based on random fibre mats and (ii) a paper making process based on chopped fibres. The influence of fibre length and fibre content on stiffness, strength and impact strength of these so-called natural-fibre-mat-reinforced thermoplastics (NMTs) is reported and compared with data for glass-mat-reinforced thermoplastics (GMTs), including the influence of the use of maleic-anhydride grafted PP for improved interfacial adhesion. In addition some preliminary data on the influence of fibre diameter on composite stiffness and strength is reported. The data is compared with the existing micro-mechanical models for strength and stiffness. A good agreement was found between theory and experiment in case of stiffness whereas in the case of strength the experimental values fall well below the theoretical predictions. Results indicated that NMTs are of interest for low-cost engineering applications and can compete with commercial GMTs when a high stiffness per unit weight is desirable. Results also indicated that future research towards significant improvements in tensile and impact strength of these types of composites should focus on the optimisation of fibre strength rather than interfacial bond strength.
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The use of natural fibres instead of man made fibres, as reinforcements in thermoplastics, gives interesting alternatives for production of low cost and ecologically friendly composites. In this work different commercially available semi-finished natural fibre mat reinforced thermoplastics (NMT) composites have been studied. Mechanical properties and microstructure of different NMT composites were investigated and compared to conventional GMT (glass fibre mat reinforced thermoplastic) composites and pure polypropylene (PP). The study included also NMT composites manufacturing processing parameters as processing temperatures and pressure during compression moulding. The results showed that NMT composites have a high stiffness compared to pure polymer and the NMT with a high fibre content (50% by weight) showed even better stiffness than the GMT. The GMT composites had superior strength and impact properties compared to the NMT which might be due to the relatively low strength of the natural fibres but also to poor adhesion to the PP matrix. The NMT materials showed a large dependence on direction and are therefore believed to have more fibres oriented in one direction. The stronger direction (0) of the NMT was in some cases as much as 45% better than the 90 direction.
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This article aims to determine the environmental performance of China reed fibre used as a substitute for glass fibre as reinforcement in plastics and to identify key environmental parameters. A life cycle assessment (LCA) is performed on these two materials for an application to plastic transport pallets. Transport pallets reinforced with China reed fibre prove to be ecologically advantageous if they have a minimal lifetime of 3 years compared with the 5-year lifetime of the conventional pallet. The energy consumption and other environmental impacts are strongly reduced by the use of raw renewable fibres, due to three important factors: (a) the substitution of glass fibre production by the natural fibre production; (b) the indirect reduction in the use of polypropylene linked to the higher proportion of China reed fibre used and (c) the reduced pallet weight, which reduces fuel consumption during transport. Considering the whole life cycle, the polypropylene production process and the transport cause the strongest environmental impacts during the use phase of the life cycle. Since thermoplastic composites are hardly biodegradable, incineration has to be preferred to discharge on landfills at the end of its useful life cycle. The potential advantages of the renewable fibres will be effective only if a purer fibre extraction is obtained to ensure an optimal material stiffness, a topic for further research. China reed biofibres are finally compared with other usages of biomass, biomaterials, in general, can enable a three to ten times more efficient valorisation of biomass than mere heat production or biofuels for transport.
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This paper describes a newly developed system, which enables utilisation of short flax fibres for SMC (Sheet Moulding Compound) production. It is shown that by using an evenly distributed layer of short dried flax fibres, after controlled impregnation and maturation, a homogeneous flow of the prepreg in the mould is obtained, and accordingly a flax fibre reinforced SMC can be produced. Mechanical data indicates that for applications designed with respect to stiffness, flax fibre reinforced SMC materials compete with glass fibre SMC, especially when the fibre length exceeds 25mm.
Opportunities for natural fibers in plastic composites
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K.Line and Company, Opportunities for natural fibers in plastic composites, Proceedings of Sixth International Conference on Woodfiber Á/Plastic Composites, May 14, 2001.
Now if we concentrate on auto sector, which is the main target of this research study, the projected consumption of natural fibers in the same sector by 2005 in North America is estimated as 45 million kg (K.Line and Company, 2001), which translates into final product of 69 million kg
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Food, Ontario (Baxter and Scheifele). Now if we concentrate on auto sector, which is the main target of this research study, the projected consumption of natural fibers in the same sector by 2005 in North America is estimated as 45 million kg (K.Line and Company, 2001), which translates into final product of 69 million kg (65% fiber content);
Glass industry analysis brief Available from http://www.eia.doe.gov/emeu/mecs/iab/glass Greenhouse gases, global climate change, and energy. Available from http
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Gerard Van Erp. 'Engineered fiber composites */opportunities for a new smart industry in south east Queensland'. Proceedings of 17th Queensland Regional Development Conference, Australia. Glass industry analysis brief. Available from http://www.eia.doe.gov/emeu/mecs/iab/glass Greenhouse gases, global climate change, and energy. Available from http://www.eia.doe.gov/oiaf/1605/ ggccebro/chapter1.html
‘Growing Industrial Hemp in Ontario-Fact Sheet
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Baxter B, Scheifele G. 'Growing Industrial Hemp in Ontario-Fact Sheet. Available from http:// www.gov.on.ca/OMAFRA/English/crops/facts/00-067.htm
Available from http://www.ppg.com/news_corporat/pr_0096 Carbon storage and sequestration by urban trees in the USA
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Corporate news. PPG Industries. Available from http://www.ppg.com/news_corporat/pr_0096.htm Nowak DJ, Crane DE. Carbon storage and sequestration by urban trees in the USA. Environmental Pollution 2002;116:381 Á/9.
Available from http://www.eia.doe.- gov/oiaf/1605/ggrpt/tbl12 Natural fiber reinforced sheet molding compound
US Carbon dioxide emissions from industrial processes, 1990 Á/2000. Available from http://www.eia.doe.- gov/oiaf/1605/ggrpt/tbl12.html Van Voorn B, Smit HHG, Sinke RJ, de Klerk B. Natural fiber reinforced sheet molding compound. Composites: Part A 2001;32:1271 Á/9.
Issues and trends in the automotive manufacturing sector Available from http://www.desrosiers.ca Emissions of greenhouse gases in US Available from http
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DesRosiers Automotive Consultants Inc. Issues and trends in the automotive manufacturing sector. Available from http://www.desrosiers.ca Emissions of greenhouse gases in US. Available from http://www.eia.doe.gov/oiaf/1605/ggrpt/carbon.htm- l#econ[Updated 5 March/02]
Crane DE. Carbon storage and sequestration by urban trees in the USA
Corporate news. PPG Industries. Available from http://www.ppg.com/news_corporat/pr_0096.htm Nowak DJ, Crane DE. Carbon storage and sequestration by urban trees in the USA. Environmental Pollution 2002;116:381 Á/9.
World carbon dioxide emissions from the consumption and flaring of fossil fuels
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Wiley, 2000. World carbon dioxide emissions from the consumption and flaring of fossil fuels, 1991 Á/2000. Available from http://www.eia.doe.gov/pub/international/ieapdf/th_01.pdf World per capita carbon dioxide emissions from fossil fuels. Available from http://www.eia.doe.gov/pub/ international/iealf/tableh1c.xls World petroleum consumption, 1991 Á/2000. Available from http://www.eia.doe.gov/pub/international/ ieapdf/t01_02.pdf
Engineered fiber composites-opportunities for a new smart industry in south east Queensland
  • Gerard Van Erp
Commercial grade laminates for auto industry
  • Azdel Inc