Journal articles: 'Composite polymère conducteur'

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Hamouni, Mohammed, and Smaïn Khaldi. "Transition état conducteur/état isolant d'un polymère conducteur composite." Revue des composites et des matériaux avancés 15, no. 2 (August 23, 2005): 157–72. http://dx.doi.org/10.3166/rcma.15.157-172.

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Hanouni, Mohammed, and Smaïn Khaldi. "Application des polymères conducteurs composites au blindage électromagnétique Cas du polymère conducteur composite HDPE/PA-Ag." Revue des composites et des matériaux avancés 19, no. 2 (August 31, 2009): 201–13. http://dx.doi.org/10.3166/rcma.19.201-213.

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Dang, Zhi-Min, Jin-Kai Yuan, Jun-Wei Zha, Peng-Hao Hu, Dong-Rui Wang, and Zhong-Yang Cheng. "High-permittivity polymer nanocomposites: Influence of interface on dielectric properties." Journal of Advanced Dielectrics 03, no. 03 (July 2013): 1330004. http://dx.doi.org/10.1142/s2010135x13300041.

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Flexible dielectric composites with high permittivity have been extensively studied due to their potential applications in high-density energy capacitors. In this review, effects of interface characteristics on the dielectric properties in the polymer-based nanocomposites with high permittivity are analyzed. The polymer-based dielectric composites are classified into two types: dielectric–dielectric (DD, ceramic particle-polymer) composites and conductor–dielectric (CD, conductive particle-polymer) composites. It is highly desirable for the dielectric–dielectric composites to exhibit high permittivity at low content of ceramic particles, which requires a remarkable interface interaction existing in the composite. For conductor–dielectric composites, a high permittivity can be achieved in composite with a small amount of conductor particle, but associated with a high loss. In this case, the interface between conductor and polymer with a good insulating characteristic is very important. Different methods can be used to modify the surface of ceramic/conductor particles before these particles are dispersed into polymers. The experimental results are summarized on how to design and make the desirable interface, and recent achievements in the development of these nanocomposites are presented. The challenges facing the fundamental understanding on the role of interface in high-permittivity polymer nanocomposites should be paid a more attention.

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André, A., P. Degobert, F. Epron-Cognet, F. Henry, and P. Michel. "Élaboration de composites « polymères/polymères conducteurs »." Journal de Chimie Physique 92 (1995): 875–78. http://dx.doi.org/10.1051/jcp/199592875.

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Yu, Zhengwei, Zhenqing Wang, Hao Li, Jianxin Teng, and Lidan Xu. "Shape Memory Epoxy Polymer (SMEP) Composite Mechanical Properties Enhanced by Introducing Graphene Oxide (GO) into the Matrix." Materials 12, no. 7 (April 3, 2019): 1107. http://dx.doi.org/10.3390/ma12071107.

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Shape memory epoxy polymer (SMEP) composite specimens with different graphene oxide (GO) contents were manufactured to study the effects of GO mass fractions on epoxy polymer composites. While ensuring the shape memory effect of SMEP, the addition of GO also remarkably strengthened the mechanical performance of the polymers. Analyses of the epoxy polymer composites’ thermal, mechanical, and shape memory performance were conducted through carrying out dynamic mechanical analysis (DMA), thermogravimetric analysis (TGA), and static tensile, three-point bending, impact, and shape memory tests. Moreover, the tensile fracture, bending fracture, and impact fracture interfaces of epoxy resin composites were examined with scanning electron microscopy. The final test results indicated that when the GO content was 0.8 wt %, SMEP composites had good shape memory performance and optimum thermal and mechanical performance.

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Wang, Xin-Tao, Yun-Long Chen, and Li Ma. "The manufacture and characterization of composite three-dimensional re-entrant auxetic cellular structures made from carbon fiber reinforced polymer." Journal of Composite Materials 52, no. 23 (March 14, 2018): 3265–73. http://dx.doi.org/10.1177/0021998318764021.

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In recent years, three-dimensional auxetic structures have attracted great interest. Generally, three-dimensional auxetic structures are of complicate geometries which make them difficult to fabricate, benefiting from the development of additive manufacturing technologies, many three-dimensional auxetic structures can be made from metals or polymers. However, to the authors' knowledge, the additive manufacturing technology of fiber reinforced polymer is not fully developed, and none three-dimensional auxetic structure made from fiber reinforced polymer has been reported before. To integrate the high specific stiffness, high specific strength, and light weight merits of high-performance fiber reinforced polymer composites into three-dimensional auxetic structures with unique properties, research on composite three-dimensional auxetic structures made from fiber reinforced polymer should be conducted. This paper presents the composite three-dimensional re-entrant auxetic structures made from carbon fiber reinforced polymer laminates using an interlocking assembly method. The auxetic nature of the composite structure has been verified by experimental testing and finite element simulations. Based on the finite element models, the dependences of the Poisson's ratio and effective compression modulus of the composite auxetic three-dimensional re-entrant structure on the re-entrant angle have been studied and compared to metal three-dimensional re-entrant structure. A comparative study of the Poisson's ratio and specific stiffness of carbon fiber reinforced polymer composite auxetic structure with the three-dimensional printed polymer and metal auxetic structures in literature has also been conducted.

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ZHANG, LIN, and Z. Y. CHENG. "DEVELOPMENT OF POLYMER-BASED 0–3 COMPOSITES WITH HIGH DIELECTRIC CONSTANT." Journal of Advanced Dielectrics 01, no. 04 (October 2011): 389–406. http://dx.doi.org/10.1142/s2010135x11000574.

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Composites have been extensively studied for dielectric and related applications. This is a review of polymer based 0–3 composites that exhibit a high dielectric constant. These composites are classified into two types: Dielectric–dielectric composite and conductor–dielectric composite. The physical principles and related models are presented with associated assumptions and approximations. In general, a dielectric–dielectric composite needs a higher concentration of the fillers to reach a high dielectric constant than a conductor–dielectric composite. The high dielectric constant observed in the conductor–dielectric composites is usually associated with a high dielectric loss and a low electric breakdown field. The experimental results are summarized to illustrate the principles for, and the achievements in, the development of these composites. The challenges facing the fundamental understanding and the further development of these composites for different applications are discussed.

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Henry, F., and JL Greffe. "Relation entre la « structure » et la conductivité complexe de composites polymère-polymère conducteur." Journal de Chimie Physique 92 (1995): 999–1004. http://dx.doi.org/10.1051/jcp/1995920999.

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Liu, Sheng, Reza Montazami, Yang Liu, Vaibhav Jain, Minren Lin, Xin Zhou, James R. Heflin, and Q. M. Zhang. "Influence of the conductor network composites on the electromechanical performance of ionic polymer conductor network composite actuators." Sensors and Actuators A: Physical 157, no. 2 (February 2010): 267–75. http://dx.doi.org/10.1016/j.sna.2009.11.022.

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Rao, Yang, Jireh Yue, and C. P. Wong. "Material Characterization of High Dielectric Constant Polymer–Ceramic Composite for Embedded Capacitor to RF Application." Active and Passive Electronic Components 25, no. 1 (2002): 123–29. http://dx.doi.org/10.1080/08827510211279.

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Embedded capacitor technology can improve electrical performance and reduce assembly cost compared with traditional discrete capacitor technology. Polymer–ceramic composites have been of great interest as embedded capacitor material because they combine the processability of polymers with the desired electrical properties of ceramics. A novel nano-structure polymer–ceramic composite with very high dielectric constant (εr∼150, a new record for the highest reportedεrvalue of nano-composite) has been developed in our previous work. RF application of embedded capacitors requires that insulating material have high dielectric constant at high frequency (GHz), low leakage current, high breakdown voltage and high reliability. A set of electrical tests have been conducted in this work to characterize the properties of the in house developed novel high dielectric constant polymer–ceramic nano-composite. Results show that this material has faily high dielectric constant in the RF range, low electrical leakage and high breakdown voltage. 85/85 TH aging test has been performed and it had shown this novel high K material has good reliability. An embedded capacitor prototype with capacitance density of35 nF/cm2has been manufactured using this nano-composite with spinning coating technology. This novel nano-composite can be used for the integral capacitors in the RF applications.

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Singh, Devendra Kumar, and Rajesh Kumar Verma. "Contemporary Development on the Performance and Functionalization of Ultra High Molecular Weight Polyethylene (UHMWPE) for Biomedical Implants." Nano LIFE 11, no. 03 (August 27, 2021): 2130009. http://dx.doi.org/10.1142/s1793984421300090.

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Polymers are widely used in biomedical implants due to their low cost, ability to shape easily in different ways, low friction and strong anti-corrosion properties. Numerous polymers such as polytetrafluoroethylene (PTFE), polyamide (PA), polymethylmethacrylate (PMMA), polyether ether ketone (PEEK), polyurethane (PU), Epoxy and ultra-high-molecular-weight polyethylene (UHMWPE) are used to develop modified biomaterials applications. Among these polymers, UHMWPE stands out as a polymer with superior customization properties to satisfy specific requirements of the human body. Investigations show that the medical-grade and prosthetic product market gained dominance in 2020, accounting for over 30% of global sales. UHMWPE has proven its dominance in tribological applications such as bearings and biomedical components. Despite its exceptional tribological properties, UHMWPE struggles with drawbacks such as poor load-bearing capability and low thermal stability. Researchers are working on various paths to develop UHMWPE composites and hybrid composites with nano/micro fillers to develop a composite framework to address these challenges. This review paper aims to amalgamate the results from these studies. It provides an overview of the studies conducted and their contribution to our current understanding of various routes taken by different researchers to enhance the tribological efficiency of UHMWPE biomaterials. This discussion may inspire the development of low friction and improved wear resistance properties in polymer (UHMWPE) biomaterial composites.

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Gołębiowski, Łukasz, Marcin Siwek, Marcin Ciesielski, Andrzej Zagórski, Sławomir Krauze, and Radosław Majewski. "Modelling and Validation of the Composite Shell of a Train Seat." Problemy Kolejnictwa - Railway Reports 64, no. 189 (December 2020): 75–84. http://dx.doi.org/10.36137/1891e.

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The subject of the modelling work and the conducted experiments is the composite shell of a train seat. The activities carried out involved designing the geometry, planning the material structure, and selecting the materials to be used. The shell was built using polymer matrix fibrous composites (i.e. FRP – Fibre Reinforced Polymer – composites), which are lighter than steel and comply with the relevant standards for strength and safety at the same time. This was followed by creating a computational model for the shell and conducting a strength analysis in accordance with the guidelines of the relevant industry standard and strength hypotheses adopted for FRP composites. The calculations were conducted using ANSYS Composite PrepPost software based on the finite element method. The article offers a strength analysis of an optimised composite shell of a train seat. Based on the guidelines obtained as a result of the conducted modelling work, a physical prototype (validation model) of the seat was created. Hot vacuum lamination technology was applied in the production process. The experimental validation of the model, producing a positive result, was conducted using a test stand owned by S.Z.T.K. TAPS – Maciej Kowalski. Keywords: train seat structure, FRP composite, FEM modelling, experimental validation

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Grzymski, Filip, Dorota Marcinczak, Tomasz Trapko, and Michał Musiał. "FRCM composites mesh anchorage – a way to increase strengthening effectiveness." MATEC Web of Conferences 251 (2018): 02044. http://dx.doi.org/10.1051/matecconf/201825102044.

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FRCM (Fabric Reinforced Cementitious Matrix) composites are the next stage of development of composite structural reinforcement after FRP (Fibre Reinforced Polymers) composites. The main element that distinguishes the newer FRCM system is the matrix of the composite – mineral matrix instead of epoxy resin. Changes in the structure of the composite, resulting from the change of the matrix, have a big impact on its work mechanisms. This paper discusses FRCM composites and shows its effectiveness in reinforced concrete elements strengthening. The basic information on FRCM mesh fibres material differences and composite failure modes are given. Current trends and directions of composite structural strengthening and the latest research in the area of increasing FRCM composite strengthening effectiveness, that are being conducted by the authors, are presented.

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Park, Min Jae, Jaehoon Bae, Jaeho Ryu, and Young K. Ju. "Fire Design Equation for Steel–Polymer Composite Floors in Thermal Fields Via Finite Element Analysis." Materials 13, no. 23 (December 7, 2020): 5573. http://dx.doi.org/10.3390/ma13235573.

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Owing to the development of new materials that enhance structural members in the construction field, steel–polymer composite floors have been developed and applied to steel structures. Similar to a sandwich system, steel–polymer composite floors consist of polymers between two steel plates. The structural performance of full-scale composite floors at ambient conditions has been investigated. Additionally, experiments were conducted on analytical models to predict both thermal behavior under fire, including fire resistance based on a small-scale furnace. To evaluate the fire resistance of full-scale steel–polymer composite floors, the thermal behavior and temperature distribution of composite floors should be investigated. Therefore, the temperature distributions of the full-scale composite floors were estimated using the verified analytical model in this study. Furthermore, to determine the fire design equation of steel–polymer composite floors in the thermal field, the correlations between variables were investigated, such as the thickness of top and bottom steel plates and polymers, as well as the fire resistance in the thermal field.

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Tański, T., and W. Matysiak. "Optical properties of PVP/ZnO composite thin films." Journal of Achievements in Materials and Manufacturing Engineering 1, no. 82 (May 1, 2017): 5–11. http://dx.doi.org/10.5604/01.3001.0010.2071.

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Purpose: The aim of the work was the preparation of thin composite layers from PVP polymer doped by ZnO nanoparticles using the spin coating method and the analysis of the applied reinforcing phase on the morphology and optical properties of obtained composites. Design/methodology/approach: To analyse the morphology of thin coatings a technique of surface topography imaging using the atomic force microscopy (AFM) was applied. Analysis of the optical properties was conducted using absorbance spectrum in function of wavelength for all produced thin coatings using UV-Vis spectroscopy. Findings: AFM results show that mass concentration of ZnO nanoparticles of 10% in a solution of PVP/EtOH polymers has a meaningful influence on the morphology of the surface of the PVP/ZnO composite coatings. Using obtained absorbance spectra, the width of the band gap of the manufactured composite coatings were determined which were compared with a band gap values of pure polymer and used reinforcing phase. Practical implications: The analysis of the values of the energy band gap of the manufactured materials showed that both for pure polymer and composite coatings values of energy band gap are similar approx. 4 eV at the same time decrease the degree of absorption of electromagnetic radiation caused by the increasing concentration of the reinforcing phase, which indicates the broad possibilities of application of this type of the material.

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Służałek, Grzegorz, Piotr Jan Duda, and Henryk Wistuba. "Tribological Characteristics of Anodic Oxide Coat (AOC) Modified - Sealed up the Polymer." Solid State Phenomena 199 (March 2013): 209–14. http://dx.doi.org/10.4028/www.scientific.net/ssp.199.209.

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The paper represents the results of investigations conducted on the tribological test for the conditions of the friction of technically dry. Analysis stereological counter-specimen was subjected from AOC and AOC modified sealed up the polymers that is composites coats. Polymerization occurred at a temperature below the recrystallization temperature of the alloy EN AW 5251. The values of the coefficient of the friction, and the results of investigations AFM (atomic force microscopy) and the parameters of the roughness were compared. The tribological properties composites are investigated by using the pin-on-disk type rotational wear tester T-01 M. This paper shows models 3D of the AOC modified polymer and the mechanism of wearing. Tribological measurements show reduced wear and friction of the composite coatings as compared with the pure anodic oxide

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Bidan, G. "Matériaux composites incluant des polymères conducteurs électroniques : revue bibliographique." Journal de Chimie Physique 86 (1989): 45–60. http://dx.doi.org/10.1051/jcp/1989860045.

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Skipina, Blanka, Dusko Dudic, Dusan Kostoski, and Jablan Dojcilovic. "Dielectrical properties of composites LDPE+CB." Chemical Industry 64, no. 3 (2010): 187–91. http://dx.doi.org/10.2298/hemind091221035s.

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There is currently great interest in the technological properties of conductive polymer composites because their cost-performance balance. They have a wide range of industrial applications -in anti-static materials, self regulating heaters, current overload and overheating protection devices, and materials for electromagnetic radiation shielding. Measurements of the electrical properties of polymer composites are one of the most convenient and sensitive methods for studying polymer structure. A polymer composite differs substantially from a free polymer in a wide range of properties. The presence of filler affects both the electrical, as well as mechanical properties. One of the most important characteristics of conductive polymer composites is that their electrical conductivity increases nonlinearly with the increase of the concentration of filler particles. When the concentration of filler particles reaches a certain critical value, a drastic transition from an electrical insulator to a conductor is exhibited. This conductivity behavior resulting in a sudden insulator-conductor transition is ascribed to a percolation process, and the critical filler concentration at which the conductivity jump occurs is called ?percolation threshold?. In the past few years, a lot of studies have been carried out to analyze the percolation phenomenon and mechanisms of the conductive behavior in conductive polymer composites. It has been established that the electrical conductivity of conductive polymer composites uncommonly depends on the temperature. Some of such composites show a sharp increase and/or decrease in electrical conductivity at specific temperatures. The conductive temperature coefficient (CTC) of conductive polymer composites has been widely investigated. In these work we investigated how concentration of the CB affects the dielectrical properties of the composite LDPE+CB. The ac electrical conductivity, ?ac, for such composites was measured. The temperature and frequency dependence of the dissipation factor were analyzed. It was found that the ac conductivity and dissipation factor were highly affected by the concentration of the filler.

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Finegan, I. C., and R. F. Gibson. "Improvement of Damping at the Micromechanical Level in Polymer Composite Materials Under Transverse Normal Loading by the Use of Special Fiber Coatings." Journal of Vibration and Acoustics 120, no. 2 (April 1, 1998): 623–27. http://dx.doi.org/10.1115/1.2893872.

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This paper describes preliminary results from a systematic analytical study of the improvement of damping in polymer composites at the micromechanical level under transverse normal loading by the use of special fiber coatings. Since shear deformations are important in damping of viscoelastic polymers, and large shear strains are generated in the region of the fiber/matrix interface, one idea for improving damping is to put a fiber coating made from a highly dissipative material in this region. A finite element model based on a “representative volume element” or repeating element of a continuously reinforced coated fiber composite is used to study damping under transverse normal loading. The micromechanical composite model investigated is a unidirectional graphite/epoxy with an acrylic polymer as the fiber coating material. Both two and three dimensional finite element models are analyzed in order to compare the influence of plane stress and plane strain conditions on the damping and stiffness properties of the composite micromechanical model. Parametric studies are conducted by using a two dimensional plane strain finite element model in order to illustrate how the coating applied to the fiber influences dynamic properties of the composite structure. The parametric studies are done with particular emphasis on the effects of frequency, temperature, and fiber coating thickness on the damping of the composite structure.

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Sapuan, S. M. "Concurrent Engineering in Natural Fibre Composite Product Development." Applied Mechanics and Materials 761 (May 2015): 59–62. http://dx.doi.org/10.4028/www.scientific.net/amm.761.59.

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In this paper a study of concurrent engineering in the development of product from natural fibre composites is presented. As far as the natural fibre composites are concerned, concurrent engineering is strongly linked to the design for sustainability because the design of natural fibre composite products fulfils the requirement of the design for sustainability, i.e. design for well-being of future generation. A study of the development of food packaging materials has been conducted. This study involved the development of sugar palm starch bio-polymer, selection of the most suitable bio-polymer, development of sugar palm fibre reinforced bio-polymer composites and design for food packaging of sugar palm fibre, specifically the sugar palm polymer composites.

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Bedi, Raman, S. P. Singh, and Rakesh Chandra. "Flexural Fatigue-Life Assessment and Strength Prediction of Glass Fibre Reinforced Polymer Concrete Composites." ISRN Materials Science 2014 (March 27, 2014): 1–8. http://dx.doi.org/10.1155/2014/928278.

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The paper presents the results of an investigation conducted to assess the fatigue-life and prediction of flexural fatigue strength of polymer concrete composites based on epoxy resin as binder material. Three point flexural fatigue tests were conducted on polymer concrete specimens using MTS servo controlled actuator, to obtain the fatigue lives of the composites at different stress levels. One hundred and thirty-seven specimens of size 40×40×160 mm were tested in flexural fatigue. Forty-three static flexural tests were also conducted to facilitate fatigue testing. It has been observed that the probabilistic distribution of fatigue-life of polymer concrete composite (PCC) and glass fibre reinforced polymer concrete composite (GFRPCC), at a particular stress level, approximately follows the two-parameter Weibull distribution, with statistical corelation coefficient values exceeding 0.90. The fatigue strength prediction model, representing S-N relationship, has been examined and the material coefficients have been obtained for GFRPCC containing 0.5% and 1.0% glass fibres. Design fatigue lives for GFRPCC containing different contents of glass fibres have been estimated for acceptable probabilities of failure and compared with those of PCC.

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Ortega-Jimenez, Cesar Humberto, Eduardo Ardón, Jose Pineda, Carlos Ventura, Carlos Núñez, Darwin Núñez, and Carlos Romero. "Recycled Polymer Concrete Composite: A Retrospective Review of the Literature and Framework for Thermal Comfort in Homes." Materials Science Forum 1015 (November 2020): 15–21. http://dx.doi.org/10.4028/www.scientific.net/msf.1015.15.

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The aim of this paper is to review the literature on Materials science to identify the current research and to provide direction for future research in thermal properties of the concrete block composite, either with Polyethylene Terephthalate (PET) or Polystyrene (PS), presenting the opportunity to make an important methodological contribution by applying systematic review in three areas of Materials science: Composites, Building Materials, as well as Testing and Evaluation of Materials. This is a growing interdisciplinary field since there are no current comparative papers addressing both PET and PS in the same research for concrete composites. Papers investigating to what extent, what type and how academic publications are integrated on the analysis of the characteristics of the two recycled polymers (PET and PS), to improve the thermal properties of the concrete block and contribute to the research of sustainable thermal comfort in homes. They were reviewed, keywords were identified within a framework of composites, building materials, as well as testing and evaluation of materials, and a lexical analysis of the papers was conducted. The results of current research show that both forms of recycling (PS and PET), combined with concrete, have sustainability in thermal comfort. The analysis reveals that previous research has focused on PET-Concrete (i.e., concrete-PET polymer composite) since it is more viable, due to its large amount of recycling. While this has benefited home builders in their ability to respond with some thermal comfort with higher construction efficiency, it also clarifies that there has been research done on PS-Concrete (i.e., concrete-PS polymer composite), presenting greater thermal comfort, because it has lower thermal conductivity. This finding suggests the need for further research within this narrow field, with absence of data, since most prescriptive recommendations have not been tested and lack practical applications, which is why the need for more empirical and experimental studies are identified. Based on the novelty of the PET or PS recycling concepts, we highlight the need of better collaboration between academic disciplines, such as engineering and architecture to provide better experimental evidence for recycling of polymers, including empirical approaches for the different types of composites and aggregate distributions, which can be made with concrete to improve thermal insulation performance and energy savings for manufacturers.

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Hyvärinen, Marko, Svetlana Butylina, and Timo Kärki. "Accelerated and Natural Weathering of Wood-Polypropylene Composites Containing Pigments." Advanced Materials Research 1077 (December 2014): 139–45. http://dx.doi.org/10.4028/www.scientific.net/amr.1077.139.

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In general, wood-polymer composites are vulnerable to weathering factors such as UV radiation, moisture, freeze-thaw action. Weathering can cause discoloration, chalking, dimensional change, and loss of mechanical properties of wood-polymer composites. This comparative study was focused on weatherability of wood–polypropylene composites made with and without pigments. Two types of inorganic pigments were applied: carbon black master-batch and synthetic iron oxide. Wood-polypropylene composite made without pigment was used as a reference. Also, composites prepared with addition of wollastonite were tested. The composite samples were exposed to outdoor weathering and in a parallel the accelerated UV weathering was conducted in xenon weathering chamber for the 2000 hours. The colour change was estimated by spectrophotometric method, and the change of Charpy impact strength after weathering was determined. The surface morphology was studied with scanning electron microscopy (SEM). The addition of pigments decreased the lightness of non-weathered composites. The change of lightness and total colour change of weathered composites were affected a lot by type of pigment and method of weathering. As, expected wood-polypropylene composite made with carbon black showed the best results in colour stability of composites exposed to weathering. SEM showed that accelerated weathering in the xenon chamber caused more significant changes in the morphology of the polymer surface layer of the composites than outdoor weathering. Charpy impact strength of all studied composites was found to retain after 2000 hours of outdoor weathering, although accelerated weathering caused significant reduction of Charpy impact strength of these composites.

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Ghaemi, Mahdi, Angelo Di Tommaso, and Cristina Gentilini. "An Experimental Investigation on Pull-Off Tests Conducted on FRP Composites Applied to Brick Units." Key Engineering Materials 817 (August 2019): 421–26. http://dx.doi.org/10.4028/www.scientific.net/kem.817.421.

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In the present study, a series of pull-off tests is performed to determine the bonding properties of fiber reinforced polymer (FRP) composites applied to a brittle substrate. Pull-off test is simple, fast and cheap and it is generally employed to evaluate the bond strength between the composite and the substrate. It is a procedure that can be easily performed on-site for checking the quality of the reinforcement adhesion.A steel composite made of a unidirectional steel fabric embedded in an organic matrix (bi-component epoxy resin) was applied to the surface of fired-clay bricks. A shallow core perpendicular to the surface was realized in the test specimen, leaving the core attached to the brick. A steel dolly was glued to the external surface of the core using epoxy adhesive. A loading device was employed to apply the tensile force until failure. The effects of moisture presence on the substrate and shape of the cores on the pull-off strength were investigated.

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Ha, Ji-Hwan, Soon-Kook Hong, Jae-Kwan Ryu, Joonwon Bae, and Sung-Hoon Park. "Development of Multi-Functional Graphene Polymer Composites Having Electromagnetic Interference Shielding and De-Icing Properties." Polymers 11, no. 12 (December 14, 2019): 2101. http://dx.doi.org/10.3390/polym11122101.

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We developed a multi-functional graphene composite with electromagnetic interference (EMI) shielding and de-icing properties. Two-dimensional graphene fillers were homogeneously dispersed in a polymer by three-roll milling. The electrical properties and percolation threshold of the graphene composites were measured with various graphene contents. The variation in the EMI shielding properties of the graphene composites with respect to the filler content was measured. The shielding efficiency improved with increasing graphene filler content. Furthermore, we conducted electrical heating tests on the graphene composites. The composites could be heated rapidly to 200 °C by electrical Joule heating with low electric power because of the high electrical conductivity of the composite. Moreover, the composite film was suitable for application in a de-icing unit because of its rapid and homogenous heating performance.

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Haase, Hanna, and Tom Schanz. "Hydro-mechanical properties of Calcigel-polyacrylamide composites." Clay Minerals 50, no. 3 (August 2015): 377–89. http://dx.doi.org/10.1180/claymin.2015.050.3.10.

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AbstractCalcigel bentonite-polyacrylamide (PAA) composites were investigated for their formation characteristics and their macroscopic hydro-mechanical and microscopic structural properties. The composites prepared were different in terms of the polymer charge, i.e. cationic (PAA+), anionic (PAA−), non-ionic (PAA°) and in terms of the polymer-to-clay ratio. The latter varied according to the individual maximum sorption capacity established from adsorption isotherms. Oedometer and waterretention testswere conducted on composites prepared under initial slurry conditions. The microstructure of the composites was investigated using environmental scanning electron microscopy (ESEM). At low stress, distinctly increased void ratios were found for all types of the composites, whereas under highstress conditions only the PAA+-composite prepared at 100% of the maximum sorption capacity showed an increase in void ratio. Analyses by ESEM on this composite indicated structural changes related to the preferential face-to-face aggregation, which help to explain the macroscopic behaviour and also account for the increased hydraulic permeabilities observed.

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Zheng, Binwei, Chuanshuang Hu, Litao Guan, Jin Gu, Huizhang Guo, and Weiwei Zhang. "Structural Characterization and Analysis of High-Strength Laminated Composites from Recycled Newspaper and HDPE." Polymers 11, no. 8 (August 6, 2019): 1311. http://dx.doi.org/10.3390/polym11081311.

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Recycled newspaper (NP) shows excellent potential as a reinforcement for polymer composites. Herein, high-strength laminated composites were prepared by using NP laminas as reinforcement and high-density polyethylene (HDPE) films as matrix. Physical and mechanical properties of the laminated composites were measured. It was found that the flexural strength of the composites had a good linear relationship to its density, with R2 = 0.9853. The flexural and tensile strength of the composites at the maximum density (1.40 g/cm3) reached up to 95.6 ± 2.4 MPa and 99.4 ± 0.8 MPa, respectively. SEM results showed that NP layer inside the composite became compact at the hot pressing time of 40 min, because the melted HDPE permeated into the NP layers to bond the NP fibers. Quantitative description of the composite porosity was conducted according to the density of the composite. The 24-h water absorption of the composite was highly related to its porosity, with R2 = 0.8994. This study reveals that density of laminated composites is an important parameter, which could be used to forecast the mechanical strength, and its derived value, porosity of the composites, could be used to predict the water absorption behavior of the composite.

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Munawar, Rose Farahiyan, Nurul Hayati Jamil, Mohd Khairul Shahril, Skh Muhammad Skh Abdul Rahim, Muhammad Zaimi Zainal Abidin, M. A. Azam, and Kok Tee Lau. "Development of Green Composite: Pineapple Leaf Fibers (PALF) Reinforced Polylactide (PLA)." Applied Mechanics and Materials 761 (May 2015): 520–25. http://dx.doi.org/10.4028/www.scientific.net/amm.761.520.

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Green composite material has become the most desired material to replace polymer composites made from fossil oil. Besides having advantages over its biodegradability and quality performances, the material sources are abundant and renewable. Therefore, this research focused on developing green composite which is derived from a combination of pineapple leaf fibers (PALF) and Polylactide (PLA). PALF is extracted from pineapple leaves which are easily found during harvesting pineapple plantation. In order to study the influences of different fibres characterization, the fibres were extracted from different types of pineapple available in Malaysia, namely Moris Gajah, Jasopine, Maspine, and N36. The main objective of this study was to investigate the physical and mechanical properties of this green composite. The physical testing was carried out to determine water absorption while the tensile and bending tests were conducted for mechanical testing. For the purpose of comparing the material properties, PALF reinforced polypropelene (PP) was developed too. Based on the result, Jasopine fibre shows the highest tensile and flexural strength for the combination of both polymers in comparison to the other types of PALF.

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Talib, Anis Adilah Abu, Aidah Jumahat, Mohammad Jawaid, Napisah Sapiai, and Alcides Lopes Leao. "Effect of Wear Conditions, Parameters and Sliding Motions on Tribological Characteristics of Basalt and Glass Fibre Reinforced Epoxy Composites." Materials 14, no. 3 (February 2, 2021): 701. http://dx.doi.org/10.3390/ma14030701.

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Basalt fibre is a promising mineral fibre that has high potential to replace synthetic based glass fibre in today’s stringent environmental concern. In this study, friction and wear characteristics of glass and basalt fibres reinforced epoxy composites were studied and comparatively evaluated at two test stages. The first stage was conducted at fixed load, speed and distance under three different conditions; adhesive, abrasive and erosive wear, wherein each composite specimens slide against steel, silicon carbide, and sand mixtures, respectively. The second stage was conducted involving different types of adhesive sliding motions against steel counterpart; unidirectional and reciprocating motion, with the former varied at pressure—velocity (PV) factor; 0.23 MPa·m/s and 0.93 MPa·m/s, while the latter varied at counterpart’s configuration; ball-on-flat (B-O-F) and cylinder-on-flat (C-O-F). It was found that friction and wear properties of composites are highly dependent on test conditions. Under 10 km test run, Basalt fibre reinforced polymer (BFRP) composite has better wear resistance against erosive sand compared to Glass fibre reinforced polymer (GFRP) composite. In second stage, BFRP composite showed better wear performance than GFRP composite under high PV of unidirectional sliding test and under B-O-F configuration of reciprocating sliding test. BFRP composite also exhibited better friction properties than GFRP composite under C-O-F configuration, although its specific wear rate was lower. In scanning electron microscopy examination, different types of wear mechanisms were revealed in each of the test conducted.

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Connor, Marco T., Saibal Roy, Tiberio A. Ezquerra, and Francisco J. Baltá Calleja. "Broadband ac conductivity of conductor-polymer composites." Physical Review B 57, no. 4 (January 15, 1998): 2286–94. http://dx.doi.org/10.1103/physrevb.57.2286.

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Peng, Yan, Huaizhi Liu, Yumeng Xin, and Jiuyang Zhang. "Rheological conductor from liquid metal-polymer composites." Matter 4, no. 9 (September 2021): 3001–14. http://dx.doi.org/10.1016/j.matt.2021.06.046.

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Gong, Chaokun, Jiajie Liang, Wei Hu, Xiaofan Niu, Sungwon Ma, H. Thomas Hahn, and Qibing Pei. "A Healable, Semitransparent Silver Nanowire-Polymer Composite Conductor." Advanced Materials 25, no. 30 (June 24, 2013): 4186–91. http://dx.doi.org/10.1002/adma.201301069.

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Akash, K. Chikkanna Anil, K. G. Girisha, and K. V. Sreenivas Rao. "Effect of Fibre Orientation on Specific Gravity, Hardness, Flexural Strength and Tensile Properties of Jute/Hemp Hybrid Laminate Composite." Applied Mechanics and Materials 766-767 (June 2015): 75–78. http://dx.doi.org/10.4028/www.scientific.net/amm.766-767.75.

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Bio-composites are taking over the polymer based composites due to their multi fold advantages. In this work, the natural fibre (jute-hemp) hybrid composite was prepared by traditional hand-lay-up method. The hardness, tensile and flexural properties of the composite specimen was evaluated in order to study the effect of fibres and fibre orientations using standard procedures. A significant improvement in hardness (114RHN), tensile (79.13mpa) and flexural (120.06mpa) properties were observed with fibre orientation of 900 compare to 300 & 450 orientations. Specific gravity test were conducted by using ASTM D792 standard at the temperature of 230c. The specific gravity was found to increase for 900 orientation of the fibre in the composite. It is also observed that the polyester based hybrid composite exhibits higher values of mechanical properties compared to epoxy based hybrid composites.

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Narita, Fumio, Yinli Wang, Hiroki Kurita, and Masashi Suzuki. "Multi-Scale Analysis and Testing of Tensile Behavior in Polymers with Randomly Oriented and Agglomerated Cellulose Nanofibers." Nanomaterials 10, no. 4 (April 7, 2020): 700. http://dx.doi.org/10.3390/nano10040700.

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Cellulose nanofiber (CNF) has been accepted as a valid nanofiller that can improve the mechanical properties of composite materials by mechanical and chemical methods. The purpose of this work is to numerically and experimentally evaluate the mechanical behavior of CNF-reinforced polymer composites under tensile loading. Finite element analysis (FEA) was conducted using a model for the representative volume element of CNF/epoxy composites to determine the effective Young’s modulus and the stress state within the composites. The possible random orientation of the CNFs was considered in the finite element model. Tensile tests were also conducted on the CNF/epoxy composites to identify the effect of CNFs on their tensile behavior. The numerical findings were then correlated with the test results. The present randomly oriented CNF/epoxy composite model provides a means for exploring the property interactions across different length scales.

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Maeder, Thomas, Caroline Jacq, Ludivine Ammon, and Perer Ryser. "Tuneable PTC effect in polymer-wax-carbon composite resistors." Microelectronics International 31, no. 3 (August 4, 2014): 143–48. http://dx.doi.org/10.1108/mi-12-2013-0079.

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Purpose – The purpose of this paper is to study tuneable positive temperature coefficient (PTC) effect in polymer-wax-carbon composite resistors. The resistivity dependence on temperature of composite resistors made of carbon fillers dispersed in an organic matrix is known to be strongly affected by the matrix thermal expansion. High PTC effects, i.e. essentially switching from resistive to quasi-insulating behaviour, can be caused by phase changes in the matrix and the assorted volume expansion, a behaviour that has been previously shown with both simple organic waxes and semi-crystalline polymers. However, waxes become very liquid on melting, possibly resulting in carbon sedimentation, and tuneability of semi-crystalline polymers is limited. Design/methodology/approach – The authors therefore study a ternary polymer-wax-conductor (ethylcellulose-octadecanol-graphite) composite resistor system, where polymer and wax fuse to a viscous liquid on heating, and re-solidify and separate by crystallisation of the wax on cooling. Findings – It is shown that with appropriate formulation, the resulting resistors exhibit strong PTC effects, linked with the melting and crystallisation of the wax component. The behaviour somewhat depends on sample history, and notably cooling speed. Research limitations/implications – The phase equilibria and transformation kinetics of the polymer-wax system (including possible wax polymorphism), as well as the exact mechanism of the conductivity transition, remain to be investigated. Originality/value – As many compatible polymer-wax systems with different melting/solidification behaviours are available, ternary polymer-wax-conductor composite PTC resistors allow a high tuneability of properties. Moreover, the high viscosity in the liquid state should largely avoid the sedimentation issues present with binary wax-conductor systems.

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Chavan, Vithal Rao, K. R. Dinesh, K. Veeresh, Veerabhadrappa Algur, and Manjunath Shettar. "Influence of post curing on GFRP hybrid composite." MATEC Web of Conferences 144 (2018): 02011. http://dx.doi.org/10.1051/matecconf/201814402011.

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Composite materials for the most part depicted as the mixes of two or more materials that outcome in the unmistakable properties than that of guard materials. Fibre strengthened plastics have been all around utilized for get-together flying machine and transport key parts as a delayed consequence of their specific mechanical and physical properties, for example, high particular quality and high particular robustness. Another pertinent application for fibre maintained polymeric composites (particularly glass fibre strengthened plastics) is in the electronic business, in which they are utilized for passing on printed wiring sheets. The utilization of polymer composite materials is winding up being powerfully essential. The present work delineates the change and mechanical portrayal of new polymer composites including glass fibre fortress, epoxy and maple cellulose fibre. The starting late made composites are delineated for their mechanical properties. The composite spreads were set up by utilizing hand layup framework. The experiments were conducted on and studied the effect of post curing on hybrid composites. The result reveals that the samples only with natural fibre have more promising results compared with synthetic fibre. The synthetic fibres get wrinkled due to post curing were as no such visuals in the natural fibres.

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Gadyal, M. A., and K. S. Venkatesh. "Synthesis of Polyaniline-Graphite Nano-Composites." Material Science Research India 12, no. 1 (April 8, 2015): 85–88. http://dx.doi.org/10.13005/msri/120114.

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The polyaniline belongs to the group of electronically conducting polymers. The graphite is anisotropic, being a good electrical and thermal conductor within the layers. One of the more important groups of materials in our lives today is composite material. The nano-composites provide reinforcing efficiency because of their high aspect ratios In this paper, synthesis and characterization polyaniline- graphite as a novel eco-friendly nano-composite material is reported.

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Seyhan, A. Tuğrul. "A Statistical Study of Fatigue Life Prediction of Fibre Reinforced Polymer Composites." Polymers and Polymer Composites 19, no. 9 (November 2011): 717–24. http://dx.doi.org/10.1177/096739111101900901.

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In this study, the tension-tension fatigue response of bidirectional woven E-glass fibre reinforced unsaturated polyester composites was experimentally determined. The composite parts were produced via continuous laminating process. The probabilistic fatigue life distribution of the produced composites at various constant stress levels was then modelled, based on the two-parameter Weibull approach. A variety of different methods including graphical, method of moments and the maximum likelihood were conducted to predict the Weibull parameters. For the sake of reliability, the composite fatigue life data gathered at each constant stress level were correlated with the approvals of Kolmogorov-Smirnow goodness-of-fit test. Furthermore, the two parameter Weibull approach was utilized to relate the composite failure probability to the number of fatigue cycles that the composite withstands under a given load. As a result, the two-parameter Weibull approach has proved to be an efficient statistical tool to assess the reliability of polymer composite structures.

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Huang, Bo, Yanqiong Li, and Wen Zeng. "Application of Metal-Organic Framework-Based Composites for Gas Sensing and Effects of Synthesis Strategies on Gas-Sensitive Performance." Chemosensors 9, no. 8 (August 14, 2021): 226. http://dx.doi.org/10.3390/chemosensors9080226.

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Gas sensing materials, such as semiconducting metal oxides (SMOx), carbon-based materials, and polymers have been studied in recent years. Among of them, SMOx-based gas sensors have higher operating temperatures; sensors crafted from carbon-based materials have poor selectivity for gases and longer response times; and polymer gas sensors have poor stability and selectivity, so it is necessary to develop high-performance gas sensors. As a porous material constructed from inorganic nodes and multidentate organic bridging linkers, the metal-organic framework (MOF) shows viable applications in gas sensors due to its inherent large specific surface area and high porosity. Thus, compounding sensor materials with MOFs can create a synergistic effect. Many studies have been conducted on composite MOFs with three materials to control the synergistic effects to improve gas sensing performance. Therefore, this review summarizes the application of MOFs in sensor materials and emphasizes the synthesis progress of MOF composites. The challenges and development prospects of MOF-based composites are also discussed.

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Koshikawa, Yusuke, and Hiromasa Goto. "Magnetic Behavior of an Iron Gluconate/Polyaniline Composite." Journal of Composites Science 5, no. 9 (September 19, 2021): 252. http://dx.doi.org/10.3390/jcs5090252.

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Oxidative polymerization conducted the synthesis of polyaniline in the presence of iron gluconate in the water. Iron gluconate is present in the resulting polyaniline (PANI). The PANI composite exhibited multiple signals in electron spin resonance, including half-field resonance of multiple spin states, the center-field resonance of polarons as radical cations in conducting polymer, and a signal from a defect in the main chain. Infrared (IR) absorption spectroscopy measurements confirmed the chemical structure of the PANI composite. The composite exhibits the mixed magnetism of PANI as a conducting polymer and Fe ions in the composite according to superconducting interference device (SQUID) measurements. Combining organic-conjugated polymers and inorganic materials can result in a unique magnetism.

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Hermawan, D., Che Mohamad Hazwan, FAT Owolabi, Deepu A. Gopakumar, M. Hasan, Samsul Rizal, NA Sri Aprilla, AR Mohamed, and HPS Abdul Khalil. "Oil palm microfiber-reinforced handsheet-molded thermoplastic green composites for sustainable packaging applications." Progress in Rubber, Plastics and Recycling Technology 35, no. 4 (July 8, 2019): 173–87. http://dx.doi.org/10.1177/1477760619861984.

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The forestry and agricultural market have been perceiving outstanding growth due to the advantages of green composites, such as cost effective in nature, environment friendly, excellent mechanical properties, and so on. Various researchers had studied the reinforcement efficiency of various natural fibers in the diverse polymer matrices. Herein, we reported the characterization of microfiber handsheet-molded thermoplastic green composites developed from the combination of oil palm empty fruit bunch (OPEFB)-based microfiber pulp as filler and polyester PP based as matrix. Refined alkaline extracted OPEFB pulp fiber was mixed at different layered composition of the composite of grafted polypropylene. The physical properties and mechanical properties were conducted according to the ASTM standard and showed substantial improvement of the handsheet-molded composite. The scanning electron microgram showed that, as the addition of OPEFB fiber loading increased, there was improved interfacial bonding except for 50% fiber loading which experience fiber pullout. The result also showed improved thermal stability compared with the neat composite. This study will be an effective platform to develop the packaging materials using polymer handsheet composite. [Formula: see text]

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Kavimani, V., P. M. Gopal, B. Stalin, Alagar Karthick, S. Arivukkarasan, and Murugesan Bharani. "Effect of Graphene Oxide-Boron Nitride-Based Dual Fillers on Mechanical Behavior of Epoxy/Glass Fiber Composites." Journal of Nanomaterials 2021 (August 7, 2021): 1–10. http://dx.doi.org/10.1155/2021/5047641.

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Graphene and its derivatives have excellent properties such as high surface area, thermal, and mechanical strength, and this fact made the researchers promote them as the possible filler material for fiber-matrix composite. The current research deals with validation on the effect of graphene oxide boron nitride filler over mechanical and thermal stability of epoxy glass fiber polymer matrix composite. The objective of this experimental investigation is to develop glass fiber reinforced polymer composites with hybrid filler addition. The matrix material selected is epoxy resin, whereas the glass fiber is selected as reinforcement, while boron nitride and graphene oxide are chosen as fillers. Compression moulding methodology is followed to develop the composites with the constant percentage of fiber loading, graphene oxide filler, and varying boron nitride content from 0 to 3 wt.% at an equal interval of 1 wt.%. The developed composite is analyzed for mechanical properties, and the fractured surface is analyzed through the scanning electron microscope. The addition of hybrid fillers enhances the fiber-matrix bonding strength and improves the thermal and mechanical properties up to a specific limit. Thermal gravimetric analysis was conducted to understand the thermal behavior of composite. The results revealed that the addition of filler improved the thermal stability of the composites.

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Ahmad Sobri, Sharizal, Robert Heinemann, and David Whitehead. "Development of Laser Drilling Strategy for Thick Carbon Fibre Reinforced Polymer Composites (CFRP)." Polymers 12, no. 11 (November 12, 2020): 2674. http://dx.doi.org/10.3390/polym12112674.

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Composites from carbon fibre reinforced polymers (CFRPs) play a significant role in modern manufacturing. They are typically used in aerospace and other industries that require high strength-to-weight ratios. Composite machining, however, remains a challenging job and sometimes is hampered by poor efficiency. Despite considerable research being conducted over the past few years on the machining of composite materials, the material nevertheless suffers from delamination, fibre loss, and imperfect finishing of the fuselage. Laser technology is becoming increasingly popular as an alternative approach to cutting and drilling composites. Experiments have been conducted with a CFRP thickness of 25.4 mm using fibre laser to test the effect of the machining parameters on the primary performance measurements. In this study, different machining criteria are used to assess the fibre laser ability of thick CFRP composites for drilling operation. The experimental findings revealed that a fibre laser is capable of penetrating a thick CFRP to a depth of 22 mm by using a novel drilling procedure.

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Basit, Abdul, Gildas L’Hostis, and Bernard Durand. "Thermo-Mechanical Testing of Epoxy Shape Memory Polymer Composites." Advanced Materials Research 570 (September 2012): 15–23. http://dx.doi.org/10.4028/www.scientific.net/amr.570.15.

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In this work the two epoxy composites the controlled behavior of composite material (CBCM) and the thermally activated symmetrical composite (SYMM) have been tested for their shape memory property. These composites have been heated above their glass transition temperature (Tg) and deformed to the same displacement. The activated position has been taken as the reference point for displacement measurements during the fixing cycle. During the recovery, two types of tests have been conducted: Unconstrained recovery test and constrained recovery test. It has been found that the recovery of CBCM plate is better as compared to the SYMM plate (unconstrained recovery test). Similarly, it has been found that CBCM plate produces larger forces of recovery than SYMM plates (constrained recovery test).

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Gawdzinska, Katarzyna, Marcin Nabialek, Katarzyna Bryll, Pawel Szymanski, and Andrei Victor Sandu. "Flexural Strength of Single Polymer Polyester Composites as a Measure of Material Degradation." Materiale Plastice 54, no. 3 (September 30, 2017): 539–42. http://dx.doi.org/10.37358/mp.17.3.4890.

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The study compares flexural strength of single polymer polyester composites. Composites under examination had the form of laminates differing in the content of the reinforcement phase and the type of material subject to simulated absorption of distilled water and sea water. Simulation tests of distilled water and sea water absorption for single polymer polyester composites with 5% to 20% reinforcing phase were made in accordance with the PN-EN ISO 62:2008 standard. The determination of the measure of degradation of the composites, the magnitude of the bending stress, was conducted in accordance with the PN-EN ISO:178 standard. This work is part of a research relating to the quality and recycling of single polymer composite materials. The testing part of the research is aimed to define the properties of examined materials before they are used commercially in specific products.

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Gomes dos Santos, D., A. G. Barbosa de Lima, P. de Sousa Costa, E. Santana de Lima, G. Moreira, and J. J. Silva Nascimento. "Water Absorption in Sisal Fiber Reinforced-Polymeric Matrix Composites: Three-Dimensional Simulations and Experiments." Diffusion Foundations 20 (December 2018): 143–54. http://dx.doi.org/10.4028/www.scientific.net/df.20.143.

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In this work was conducted a theoretical and experimental study of water absorption in polyester matrix composites reinforced with sisal fiber at temperatures of 25, 50 and 70°C. A fiber content 44.6% sisal fibers, and 55.4% polyester matrix were used in the manufacture of the polymer composite. The dimensions of the composite were 20x20x3mm3and 20x20x6mm3. Water absorption tests were conducted by immersion of the samples in a distilled water bath and the water uptake calculated by weight difference of the samples in the dry and wetted condition at different elapsed time. A three-dimensional mathematical model was developed to predict mass transfer during the water absorption inside the parallelepiped solid. Results of water absorption kinetic and moisture content distribution inside the composites showed the more favorable areas which presents delamination problems due the weakness of the fiber-matrix interface and consequently, reduction in the mechanical properties. It was found that the high water bath temperatures accelerate the absorption process and that the water absorption of the sisal reinforced polymer composite with 3 mm of thickness was faster than the with 6 mm of thickness.

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Raghu, M. J., and Govardhan Goud. "Tribological Properties of Calotropis Procera Natural Fiber Reinforced Hybrid Epoxy Composites." Applied Mechanics and Materials 895 (November 2019): 45–51. http://dx.doi.org/10.4028/www.scientific.net/amm.895.45.

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Natural fibers are widely used for reinforcement in polymer composite materials and proved to be effectively replacing synthetic fiber reinforced polymer composites to some extent in applications like domestic, automotive and lower end aerospace parts. The natural fiber reinforced composites are environment friendly, have high strength to weight ratio as well as specific strengths comparable with synthetic glass fiber reinforced composites. In the present work, hybrid epoxy composites were fabricated using calotropis procera and glass fibers as reinforcement by hand lay-up method. The fibre reinforcement in epoxy matrix was maintained at 20 wt%. In 20 wt% reinforcement of fibre, the content of calotropis procera and glass fibre were varied from 5, 10, 15 and 20 wt%. The dry sliding wear test as per ASTM G99 and three body abrasive wear test as per ASTM G65 were conducted to find the tribological properties by varying speed, load, distance and abrasive size. The hybrid composite having 5 wt% calotropis procera and 15 wt% glass fibre showed less wear loss in hybrid composites both in sliding wear test as well as in abrasive wear test which is comparable with 20 wt% glass fibre reinforced epoxy composite which marked very low wear loss. The SEM analysis was carried out to study the worn out surfaces of dry sliding wear test and three body abrasive wear test specimens.

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Hasan, K. M. Faridul, Péter György Horváth, and Tibor Alpár. "Development of lignocellulosic fiber reinforced cement composite panels using semi-dry technology." Cellulose 28, no. 6 (February 22, 2021): 3631–45. http://dx.doi.org/10.1007/s10570-021-03755-4.

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AbstractThere is a growing interest in developing cement bonded lignocellulosic fiber (LF) composites with enhanced mechanical performances. This study assessed the possibility of developing composite panels with 12 mm thickness and around 1200 kg/m3 nominal densities from ordinary Portland cements (OPC) and mixed LFs from seven different woody plants found in Hungary. Once the mixed LFs were sieved and found fine (0–0.6 mm) and medium (0.6–0.8 mm) length fibers. The optimum ratio for LF, OPC, water glass (Na2SiO3), and cement stone was found to be 1:3.5:0.7:0.07. The semi-dry process, which is a comparatively cheaper and less labor intensive technology, was used for producing the composites. After 28 days of curing, the composite panels were characterized for mechanical, physical, thermal, and morphological properties. A scanning electron microscopy (SEM) test was conducted to observe the fiber orientation in the matrix before and after the bending test, which showed the clear presence of the fibers in the composites. The FTIR (Fourier transform infrared spectroscopy) was conducted to investigate the presence of chemical compounds of LF in the composite panels. Different physical (water absorption and thickness swelling) characteristics of the composite panels were investigated. Furthermore, mechanical properties (flexural properties and internal bonding strength) of the composite panels were also found to be satisfactory. The flexural modulus and internal bonding strengths of composite panel 2 is higher than other three boards, although the flexural strength is a little lower than composite panel 1. The thermogravimetric analysis and differential thermogravimetry also indicated better thermal stability of composite panels which could be used as potential insulation panel for buildings. Graphic abstract

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Makhlouki, M., M. Morsli, A. Bonnet, A. Conan, JC Bernede, and S. Lefrant. "Propriétés de transport de composites de polymères conducteurs : polyvinyl alcool-polypyrrole." Journal de Chimie Physique 89 (1992): 1155–60. http://dx.doi.org/10.1051/jcp/1992891155.

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Chen, Qian, Piyi Du, Lu Jin, Wenjian Weng, and Gaorong Han. "Percolative conductor/polymer composite films with significant dielectric properties." Applied Physics Letters 91, no. 2 (July 9, 2007): 022912. http://dx.doi.org/10.1063/1.2757131.

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Journal articles on the topic 'Composite polymère conducteur'

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