1
|
Črešnar KP, Plohl O, Zemljič LF. Functionalised Fibres as a Coupling Reinforcement Agent in Recycled Polymer Composites. MATERIALS (BASEL, SWITZERLAND) 2024; 17:2739. [PMID: 38894002 PMCID: PMC11174083 DOI: 10.3390/ma17112739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2024] [Revised: 05/22/2024] [Accepted: 05/27/2024] [Indexed: 06/21/2024]
Abstract
This study addresses the structure-property relationship within the green concept of wood fibres with cellulose nanofibre functionalised composites (nW-PPr) containing recycled plastic polyolefins, in particular, polypropylene (PP-r). It focuses especially on the challenges posed by nanoscience in relation to wood fibres (WF) and explores possible changes in the thermal properties, crystallinity, morphology, and mechanical properties. In a two-step methodology, wood fibres (50% wt%) were first functionalised with nanocellulose (nC; 1-9 wt%) and then, secondly, processed into composites using an extrusion process. The surface modification of nC improves its compatibility with the polymer matrix, resulting in improved adhesion, mechanical properties, and inherent biodegradability. The effects of the functionalised WF on the recycled polymer composites were investigated systematically and included analyses of the structure, crystallisation, morphology, and surface properties, as well as thermal and mechanical properties. Using a comprehensive range of techniques, including X-ray diffraction (XRD), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), zeta potential measurements, and dynamic mechanical analysis (DMA), this study aims to unravel the intricate interplay of factors affecting the performance and properties of the developed nanocellulose-functionalised wood fibre-polymer composites. The interfacial adhesion of the nW-PPr polymer composites, crystallisation process, and surface properties was improved due to the formation of an H-bond between the nW coupling agent and neat PP-r. In addition, the role of nW (1.0 wt%) as a nucleating agent resulted in increased crystallinity, or, on the other hand, promoted the interfacial interaction with the highest amount (3.0% wt%, 9.0% wt%) of nW in the PP-r preferentially between the nW and neat PP-r, and also postponed the crystallisation temperature. The changes in the isoelectric point of the nW-PPr polymer composites compared to the neat PP-r polymer indicate the acid content of the polymer composite and, consequently, the final surface morphology. Finally, the higher storage modulus of the composites compared to neat r-PP shows a dependence on improved crystallinity, morphology, and adhesion. It was clear that the results of this study contribute to a better understanding of sustainable materials and can drive the development of environmentally friendly composites applied in packaging.
Collapse
Affiliation(s)
- Klementina Pušnik Črešnar
- Faculty of Mechanical Engineering, University of Maribor, 2000 Maribor, Slovenia; (O.P.); (L.F.Z.)
- Faculty of Chemistry and Chemical Engineering, University of Maribor, 2000 Maribor, Slovenia
| | - Olivija Plohl
- Faculty of Mechanical Engineering, University of Maribor, 2000 Maribor, Slovenia; (O.P.); (L.F.Z.)
| | - Lidija Fras Zemljič
- Faculty of Mechanical Engineering, University of Maribor, 2000 Maribor, Slovenia; (O.P.); (L.F.Z.)
| |
Collapse
|
2
|
Development of Hybrid Composite Utilizing Micro-Cellulose Fibers Extracted from Date Palm Rachis in the Najran Region. Polymers (Basel) 2022; 14:polym14214687. [DOI: 10.3390/polym14214687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2022] [Revised: 10/25/2022] [Accepted: 11/01/2022] [Indexed: 11/06/2022] Open
Abstract
Environmental effects can be reduced by using renewable resources in various applications. The date palm fibers (DPF) used in this study were extracted from waste date ranches of the Najran region by retting and manual peeling processes. The biocomposites were developed by reinforcing the silane-treated DPF (SDPF) at different wt.% in eugenol phthalonitrile (EPN) and difunctional benzoxazine (BA-a) copolymer. The impact strength, tensile, flexural, and dynamic mechanical properties and thermogravimetric analysis were evaluated to understand the mechanical, thermomechanical, and thermal properties. Results confirmed that 30 wt.% SDPF-reinforced poly (EPN/BA-a) composites produced the highest mechanical and thermomechanical properties, and were considered optimized SDPF reinforcement. Furthermore, hybrid composites with 30 wt.% SDPF and 15 wt.% silane-treated glass fibers (SGF) reinforcement having different lamination sequences were also studied. The lamination sequences showed a significant impact on the mechanical and thermomechanical properties, as properties were further enhanced by adding a core layer of SGF in hybrid composites. However, the thermal properties of SDPF/SGF laminates were higher than SDPF biocomposites, but the SGF lamination sequence did not produce any impact. According to the limiting oxygen and heat resistance indexes, the developed SDPF/SGF laminates are self-extinguishing materials and can be used in temperature-tolerant applications up to 230 °C.
Collapse
|
3
|
Centeno-Mesa N, Lombana-Toro O, Correa-Aguirre JP, Hidalgo-Salazar MA. Effect of fique fibers and its processing by-products on morphology, thermal and mechanical properties of epoxy based biocomposites. Sci Rep 2022; 12:15143. [PMID: 36071075 PMCID: PMC9452679 DOI: 10.1038/s41598-022-18934-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 08/22/2022] [Indexed: 11/09/2022] Open
Abstract
This work examines the morphology, mechanical and thermal properties of biocomposites based on epoxy resin-EP and fique (Furcraea andina), a native crop of South America. The EP-fique biocomposites were prepared using fique powder-FP an industrial waste generated during fique processing, nonwoven fique fiber mats-NWF and unidirectional fique fiber mats-UF oriented at 0° and 90°. The addition of fique into EP matrix restricts EP macromolecule chains movement and enhance the thermal stability of EP. SEM images showed that fique form used (powder or fiber) and mat arrangement can generate changes in the biocomposites morphology. Mechanical characterization show that fique powder and fique fibers oriented at 90° acts as fillers for the epoxy matrix while the fique fibers oriented at 0° reinforce EP matrix increasing the tensile and flexural modulus up to 5700 and 1100% respectively and tensile and flexural strength up to 277% and 820% in comparison with neat EP. The obtained results can increase the interest in researching and developing products from fique Powders and other natural fibers processing byproducts thus reducing the abundance of waste in soil and landfills and environmental concerns and suggest that the EP-fique biocomposites are promising to be used in the automotive sector.
Collapse
Affiliation(s)
- Nicolas Centeno-Mesa
- Research Group for Manufacturing Technologies GITEM, Universidad Autónoma de Occidente, Cali, Colombia
| | - Oscar Lombana-Toro
- Research Group for Manufacturing Technologies GITEM, Universidad Autónoma de Occidente, Cali, Colombia
| | - Juan P Correa-Aguirre
- Research Group for Manufacturing Technologies GITEM, Universidad Autónoma de Occidente, Cali, Colombia.
| | - Miguel A Hidalgo-Salazar
- Research Group for Manufacturing Technologies GITEM, Universidad Autónoma de Occidente, Cali, Colombia
| |
Collapse
|
4
|
Date Palm Fiber-Reinforced Recycled Polymer Composites: Synthesis and Characterization. ADVANCES IN POLYMER TECHNOLOGY 2022. [DOI: 10.1155/2022/7957456] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
In this research study, Recycled Polymer (RP) composites are synthesized by using compression molding process, initial mixtures of RP and Date Palm Fibers (DPF) with four different lengths (e.g., 2.5, 5, 7.5, and 10 mm) and weight ratios (e.g., 5, 10, 15, and 20 wt%). The RP composites utilized in this study are polyethylene and polypropylene. The mixtures of RP and DPF are heated at 80°C and then poured into a priori prepared mold. The mold is designed to have three cavities for three specimens in order to characterize them through impact, creep, and tensile tests. The results showed that the hardness and impact increased with this process. In addition, an increase in the DPF up to 15 wt% was observed with a small increase in the DPF length. High creep resistance was also observed to be 10 mm with 20 wt% in the DPF specimens. The maximum strain was obtained in a 2.5 mm fiber length with 5% of DPF due to ductility of the plastic matrix. Moreover, with a small ratio of tough DPF, short fibers are unable to block or resist rapid plastic deformation in specimens. In fact, the DPF specimens of 10 mm length with 20 wt% exhibit a high tensile strength of 78 N/mm2 in comparison with other composite specimens. This is due to the length and content of fibers, which improve transferring action and microfailure modes.
Collapse
|
5
|
Thermal Performance of Medina Date Palm Components as Thermal Insulation in Local Buildings. ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING 2022. [DOI: 10.1007/s13369-021-06538-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
|
6
|
Alshaaer M, Alqahtani O, Alharbi MMS, Alanazi AOS, Aldhafeeri KA, Ahmed MT, Alomayri T. Synthesis and Characterization of Date Palm Fiber-Reinforced Geopolymer Composite. ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING 2021. [DOI: 10.1007/s13369-021-06378-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
|
7
|
Roy PS, Garnier G, Allais F, Saito K. Strategic Approach Towards Plastic Waste Valorization: Challenges and Promising Chemical Upcycling Possibilities. CHEMSUSCHEM 2021; 14:4007-4027. [PMID: 34132056 DOI: 10.1002/cssc.202100904] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 06/13/2021] [Indexed: 06/12/2023]
Abstract
Plastic waste, which is one of the major sources of pollution in the landfills and oceans, has raised global concern, primarily due to the huge production rate, high durability, and the lack of utilization of the available waste management techniques. Recycling methods are preferable to reduce the impact of plastic pollution to some extent. However, most of the recycling techniques are associated with different drawbacks, high cost and downgrading of product quality being among the notable ones. The sustainable option here is to upcycle the plastic waste to create high-value materials to compensate for the cost of production. Several upcycling techniques are constantly being investigated and explored, which is currently the only economical option to resolve the plastic waste issue. This Review provides a comprehensive insight on the promising chemical routes available for upcycling of the most widely used plastic and mixed plastic wastes. The challenges inherent to these processes, the recent advances, and the significant role of the science and research community in resolving these issues are further emphasized.
Collapse
Affiliation(s)
- Pallabi Sinha Roy
- School of Chemistry, Monash University, Clayton, 3800, VIC, Australia
- BioPRIA, Department of Chemical Engineering, Monash University, Clayton, 3800, VIC, Australia
| | - Gil Garnier
- BioPRIA, Department of Chemical Engineering, Monash University, Clayton, 3800, VIC, Australia
- URD Agro-Biotechnologies Industrielles (ABI), CEBB, AgroParisTech, 51110, Pomacle, France
| | - Florent Allais
- BioPRIA, Department of Chemical Engineering, Monash University, Clayton, 3800, VIC, Australia
- URD Agro-Biotechnologies Industrielles (ABI), CEBB, AgroParisTech, 51110, Pomacle, France
| | - Kei Saito
- School of Chemistry, Monash University, Clayton, 3800, VIC, Australia
- BioPRIA, Department of Chemical Engineering, Monash University, Clayton, 3800, VIC, Australia
- Graduate School of Advanced Integrated Studies in Human Survivability, Kyoto University, Higashi-Ichijo-Kan, Yoshida-nakaadachicho 1, Sakyo-ku, Kyoto, 606-8306, Japan
| |
Collapse
|
8
|
Morales MA, Maranon A, Hernandez C, Porras A. Development and Characterization of a 3D Printed Cocoa Bean Shell Filled Recycled Polypropylene for Sustainable Composites. Polymers (Basel) 2021; 13:3162. [PMID: 34578062 PMCID: PMC8472922 DOI: 10.3390/polym13183162] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 09/12/2021] [Accepted: 09/15/2021] [Indexed: 11/16/2022] Open
Abstract
Natural filler-based composites are an environmentally friendly and potentially sustainable alternative to synthetic or plastic counterparts. Recycling polymers and using agro-industrial wastes are measures that help to achieve a circular economy. Thus, this work presents the development and characterization of a 3D printing filament based on recycled polypropylene and cocoa bean shells, which has not been explored yet. The obtained composites were thermally and physically characterized. In addition, the warping effect, mechanical, and morphological analyses were performed on 3D printed specimens. Thermal analysis exhibited decreased thermal stability when cacao bean shell (CBS) particles were added due to their lignocellulosic content. A reduction in both melting enthalpy and crystallinity percentage was identified. This is caused by the increase in the amorphous structures present in the hemicellulose and lignin of the CBS. Mechanical tests showed high dependence of the mechanical properties on the 3D printing raster angle. Tensile strength increased when a raster angle of 0° was used, compared to specimens printed at 90°, due to the load direction. Tensile strength and fracture strain were improved with CBS addition in specimens printed at 90°, and better bonding between adjacent layers was achieved. Electron microscope images identified particle fracture, filler-matrix debonding, and matrix breakage as the central failure mechanisms. These failure mechanisms are attributed to the poor interfacial bonding between the CBS particles and the matrix, which reduced the tensile properties of specimens printed at 0°. On the other hand, the printing process showed that cocoa bean shell particles reduced by 67% the characteristic warping effect of recycled polypropylene during 3D printing, which is advantageous for 3D printing applications of the rPP. Thereby, potential sustainable natural filler composite filaments for 3D printing applications with low density and low cost can be developed, adding value to agro-industrial and plastic wastes.
Collapse
Affiliation(s)
- Maria A. Morales
- Grupo de Diseño de Productos y Procesos (GDPP), Department of Chemical and Food Engineering, Universidad de los Andes, CR 1 18a 12, Bogotá 111711, Colombia;
| | - Alejandro Maranon
- Structural Integrity Research Group, Department of Mechanical Engineering, Universidad de los Andes, CR 1 18a 12, Bogotá 111711, Colombia;
| | - Camilo Hernandez
- Sustainable Design in Mechanical Engineering Research Group (DSIM), Department of Mechanical, Engineering, Escuela Colombiana de Ingenieria Julio Graravito, Autopista Norte AK 45 205 59, Bogotá 111166, Colombia;
| | - Alicia Porras
- Grupo de Diseño de Productos y Procesos (GDPP), Department of Chemical and Food Engineering, Universidad de los Andes, CR 1 18a 12, Bogotá 111711, Colombia;
| |
Collapse
|
9
|
Sider I, Nassar MMA. Chemical Treatment of Bio-Derived Industrial Waste Filled Recycled Low-Density Polyethylene: A Comparative Evaluation. Polymers (Basel) 2021; 13:polym13162682. [PMID: 34451221 PMCID: PMC8398065 DOI: 10.3390/polym13162682] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2021] [Revised: 08/05/2021] [Accepted: 08/06/2021] [Indexed: 11/16/2022] Open
Abstract
The search for renewable alternatives for petroleum products that can be used in industrial applications is increasing. Each year, several tons of bio-derived industrial waste is produced and most of it is burned or placed in landfills. Olive pits (OP) have unique characteristics such as abundance, renewability, and biodegradability, which can be utilized to develop new types of biocomposites. One of the most promising uses of OP is that they can reinforce the mechanical properties of polymeric biocomposites. This study describes the preparation of recycled low-density polyethylene (rLDPE) that is filled with OP flour (10, 20, 30, and 40 wt.%) using a twin-screw extruder. The effects of the chemical treatment of the OP surface (sodium hydroxide (NaOH) and dimethyl sulfoxide (DMSO)) on the bio-filler/polymer compatibility along with the produced composite's chemical, physical, mechanical, and thermal properties have been explored. Overall, the reinforced composites that were obtained with alkali-treated OP have better biocomposite properties. This indicates an improved compatibility between the bio-filler and matrix. The results are promising in terms of using OP flour in developing green composites.
Collapse
Affiliation(s)
- Ishaq Sider
- Department of Mechanical Engineering, Palestine Polytechnic University, Wadi Alhareya, Hebron P.O. Box 198, Palestine
- Correspondence: ; Tel.: +97-059-9340-136
| | - Mahmoud M. A. Nassar
- College of Applied Professions, Palestine Polytechnic University, Wadi Alhareya, Hebron P.O. Box 198, Palestine;
| |
Collapse
|
10
|
Extrusion and injection moulding induced degradation of date palm fibre - polypropylene composites. Polym Degrad Stab 2021. [DOI: 10.1016/j.polymdegradstab.2021.109641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
11
|
Nassar MMA, Alzebdeh KI, Pervez T, Al-Hinai N, Munam A, Al-Jahwari F, Sider I. Polymer powder and pellets comparative performances as bio-based composites. IRANIAN POLYMER JOURNAL 2021. [DOI: 10.1007/s13726-020-00888-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
12
|
Atmakuri A, Palevicius A, Siddabathula M, Vilkauskas A, Janusas G. Analysis of Mechanical and Wettability Properties of Natural Fiber-Reinforced Epoxy Hybrid Composites. Polymers (Basel) 2020; 12:polym12122827. [PMID: 33261200 PMCID: PMC7760148 DOI: 10.3390/polym12122827] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Revised: 11/22/2020] [Accepted: 11/24/2020] [Indexed: 12/31/2022] Open
Abstract
Natural fibers have many advantages over synthetic fibers due to their lightness, low cost, biodegradability, and abundance in nature. The demand for natural fiber hybrid composites in various applications has increased recently, because of its promising mechanical properties. In this research work, the mechanical and wettability properties of reinforced natural fiber epoxy resin hybrid composites were investigated. The main aim of this research work is the fabrication of hybrid composites and exploit its importance over individual fiber composites. The composites were fabricated based on the rule of hybridization mixture (0.4 wf) of two fibers using sets of either hemp and flax or banana and pineapple, each set with 40 wt%, as well as four single fiber composites, 40 wt% each, as reinforcement and epoxy resin as matrix material. A total of two sets (hemp/flax and banana/pineapple) of hybrid composites were fabricated by using a hand layup technique. One set as 40H/0F, 25H/15F, 20H/20F, 15H/25F, 0H/40F, and the second one as 40B/0P, 25B/15P, 20B/20P, 15B/25P, 0B/40P weight fraction ratios. The fabricated composites were allowed for testing to examine its mechanical, wettability, and moisture properties. It has been observed that, in both cases, hybrid composites showed improved mechanical properties when compared to the individual fiber composites. The wettability test was carried out by using the contact angle measurement technique. All composites in both cases, hybrid or single showed contact angle less than 90°, which is associated with the composite hydrophilic surface properties. The moisture analysis stated that all the composites responded for moisture absorption up to 96 h and then remained constant in both cases. Hybrid composites absorbed less moisture than individual fiber composites.
Collapse
Affiliation(s)
- Ayyappa Atmakuri
- Faculty of Mechanical Engineering and Design, Kaunas University of Technology, Studuntu 56, 44249 Kaunas, Lithuania; (A.P.); (A.V.); (G.J.)
- Correspondence:
| | - Arvydas Palevicius
- Faculty of Mechanical Engineering and Design, Kaunas University of Technology, Studuntu 56, 44249 Kaunas, Lithuania; (A.P.); (A.V.); (G.J.)
| | - Madhusudan Siddabathula
- Faculty of Mechanical Engineering and Design, Usha Rama College of Engineering, Telaprolu, Andhra Pradesh 521109, India;
| | - Andrius Vilkauskas
- Faculty of Mechanical Engineering and Design, Kaunas University of Technology, Studuntu 56, 44249 Kaunas, Lithuania; (A.P.); (A.V.); (G.J.)
| | - Giedrius Janusas
- Faculty of Mechanical Engineering and Design, Kaunas University of Technology, Studuntu 56, 44249 Kaunas, Lithuania; (A.P.); (A.V.); (G.J.)
| |
Collapse
|
13
|
Anti-inflammatory, anti-apoptotic, and antioxidant actions of Middle Eastern Phoenix dactylifera extract on mercury-induced hepatotoxicity in vivo. Mol Biol Rep 2020; 47:6053-6065. [PMID: 32737827 DOI: 10.1007/s11033-020-05680-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 07/07/2020] [Accepted: 07/19/2020] [Indexed: 02/01/2023]
Abstract
Mercuric chloride (MC) is a complex substance which is capable to produce free radicals. Middle Eastern Phoenix dactylifera (MEPD) is a flowering plant of palm family with potent antioxidant feature. Due to the increasing use of herbs in medicine, this study was designed to assess the effects of MEPD and MC on inflammatory apoptogenic, oxidative and histomorphometric alterations in liver. Sixty-four male rats were assigned to 8 groups including: control groups (normal group and MC (50 mg/kg)), MEPD groups (30, 90, 270 mg/kg) and MC + MEPD treated groups. All experimental groups were treated intraperitoneally and orally daily for 5 weeks. The relative expression level of apoptotic genes (p53, Bcl2 and Bax) and hepatocyte apoptotic index were analyzed. Also, Nitrite oxide (NO), lipid peroxidation (LP), Ferric Reducing Ability of Plasma (FRAP) assays were conducted to assess the antioxidant levels. Cytokines involved in inflammation, hepatic enzymes and histomorphometric parameters (hepatocytes diameter (HD) and central hepatic vein (CHV)) were evaluated. All factors showed incremental trends following MC administration (else FRAP level and Bcl2, which were decreased) in MC group than normal group (P < 0.05). In comparison with the MC group, total values in MEPD and MEPD + MC groups were decreased (P < 0.05) (except FRAP level and Bcl2, which were increased). According to the obtained data, the administration of MEPD extract has potent antioxidant property that attenuates the destructive hepatic effects of MC by initiation of cellular antioxidant pathways and restoration of pathological changes into the physiological form.
Collapse
|
14
|
Stanciu MD, Teodorescu Draghicescu H, Tamas F, Terciu OM. Mechanical and Rheological Behaviour of Composites Reinforced with Natural Fibres. Polymers (Basel) 2020; 12:polym12061402. [PMID: 32580517 PMCID: PMC7362192 DOI: 10.3390/polym12061402] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Revised: 06/15/2020] [Accepted: 06/17/2020] [Indexed: 11/18/2022] Open
Abstract
The paper deals with the mechanical behaviour of natural fibre composites subjected to tensile test and dynamic mechanical analysis (DMA). Three types of natural fibre composites were prepared and tested: wood particle reinforced composites with six different sizes of grains (WPC); hemp mat reinforced composites (HMP) and flax reinforced composite with mixed wood particles (FWPC). The tensile test performed on universal testing machine LS100 Lloyd’s Instrument highlights the elastic properties of the samples, as longitudinal elasticity modulus; tensile rupture; strain at break; and stiffness. The large dispersion of stress–strain curves was noticed in the case of HMP and FWPC by comparison to WPC samples which present high homogeneity of elastic–plastic behaviour. The DMA test emphasized the rheological behaviour of natural fibre composites in terms of energy dissipation of a material under cyclic load. Cole–Cole plots revealed the connection between stored and loss heat energy for studied samples. The mixture of wood particles with a polyester matrix leads to relative homogeneity of composite in comparison with FWPC and HMP samples which is visible from the shape of Cole–Cole curves. The random fibres from the hemp mat structure lead to a heterogeneous nature of composite structure. The elastic and viscous responses of samples depend on the interface between fibres and matrix.
Collapse
Affiliation(s)
- Mariana D. Stanciu
- Department of Mechanical Engineering, Transilvania University of Brasov, Eroilor 29, 500036 Brasov, Romania; (H.T.D.); (O.M.T.)
- Correspondence:
| | - Horatiu Teodorescu Draghicescu
- Department of Mechanical Engineering, Transilvania University of Brasov, Eroilor 29, 500036 Brasov, Romania; (H.T.D.); (O.M.T.)
| | - Florin Tamas
- Department of Civil Engineering, Transilvania University of Brasov, Eroilor 29, 500036 Brasov, Romania;
| | - Ovidiu Mihai Terciu
- Department of Mechanical Engineering, Transilvania University of Brasov, Eroilor 29, 500036 Brasov, Romania; (H.T.D.); (O.M.T.)
| |
Collapse
|