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Sergio Neves Monteiro - One of the best experts on this subject based on the ideXlab platform.

  • Tensile Behavior of Epoxy Matrix Composites Reinforced with Pure Ramie Fabric
    Characterization of Minerals Metals and Materials 2017, 2017
    Co-Authors: Caroline Gomes De Oliveira, Janine Feitosa De Deus, Ygor Macabu De Moraes, Marcos V. F. Fonseca, Djalma Souza, Frederico Muylaert Margem, Luiz Gustavo Xavier Borges, Sergio Neves Monteiro
    Abstract:

    Recently, the natural Fibers have been studied as alternative reinforcement material to the use of synthetic Fibers. Aiming to improve the properties of natural Fibers composites, it is investigated the use of natural Fibers fabrics, since they provide multidirectional reinforcement and enables the introduction of a larger Fiber volume fraction. In this work, it was investigated the tensile behavior of the epoxy matrix composites reinforced with different volume fractions of fabric made of Ramie, a highly resistant Lignocellulosic Fiber. The specimens were made by pressing the fabric with liquid resin to guarantee total impregnation, and then cutting the fabric in the mold format. Finally, the fabric layers were placed into the mold with the liquid resin and catalyst. They were cured for 24 h and tested. The results revealed an increase in the tensile strength and almost no effect in the elastic modulus with the increase of fabric volume fraction.

  • re emerging field of Lignocellulosic Fiber polymer composites and ionizing radiation technology in their formulation
    Polymer Reviews, 2016
    Co-Authors: Olgun Guven, Sergio Neves Monteiro, Esperidiana A B Moura, Jaroslaw Drelich
    Abstract:

    ABSTRACTNatural cellulose-based Fibers offer low cost, low density composite reinforcement with good strength and stiffness. Because of their annual renewability and biodegradability, natural Fibers have materialized as environmentally-friendly alternatives to synthetic Fibers in the last two decades. They are replacing synthetic materials in some traditional composites in industrial manufacturing sectors such as automotive, construction, furniture, and other consumer goods. In this work, the use of Lignocellulosic Fibers in green materials engineering, particularly their application as polymeric composite reinforcement and surface treatment via ionizing radiation are reviewed. Because these cellulose-based materials are intrinsically hydrophilic, they require surface modification to improve their affinity for hydrophobic polymeric matrices, which enhances the strength, durability, and service lifetime of the resulting Lignocellulosic Fiber-polymer composites. In spite of a long history of using chemical ...

  • Re-Emerging Field of Lignocellulosic Fiber – Polymer Composites and Ionizing Radiation Technology in their Formulation
    Polymer Reviews, 2016
    Co-Authors: Olgun Guven, Sergio Neves Monteiro, Esperidiana A B Moura, Jaroslaw Drelich
    Abstract:

    ABSTRACTNatural cellulose-based Fibers offer low cost, low density composite reinforcement with good strength and stiffness. Because of their annual renewability and biodegradability, natural Fibers have materialized as environmentally-friendly alternatives to synthetic Fibers in the last two decades. They are replacing synthetic materials in some traditional composites in industrial manufacturing sectors such as automotive, construction, furniture, and other consumer goods. In this work, the use of Lignocellulosic Fibers in green materials engineering, particularly their application as polymeric composite reinforcement and surface treatment via ionizing radiation are reviewed. Because these cellulose-based materials are intrinsically hydrophilic, they require surface modification to improve their affinity for hydrophobic polymeric matrices, which enhances the strength, durability, and service lifetime of the resulting Lignocellulosic Fiber-polymer composites. In spite of a long history of using chemical ...

  • Tensile Test of High Strength Thinner Curaua Fiber Reinforced Polyester Matrix Composite
    Materials Science Forum, 2016
    Co-Authors: Sergio Neves Monteiro, Frederico Muylaert Margem, Noan Tonini Simonassi, Rômulo Leite Loiola, Michel Picanço Oliveira
    Abstract:

    In recent years natural Fibers, especially those Lignocellulosic extracted from plants, have gained attention owing to their engineering performance as polymer composite reinforcement. It was found that some of these Lignocellulosic Fibers, such as the curaua, ramie and sisal may reach tensile strength above 1000 MPa in association with very thin diameters. Therefore. the objective of the present work was to fabricate polyester matrix composites with the highest tensile strength possible, by reinforcing with the thinnest continuous and aligned curaua Fibers. Tensile tests results of composites reinforced with 30% volume of these thinnest curaua Fibers showed a tensile strength of 135 MPa, which corresponds to one of the highest strength attained for Lignocellulosic Fiber composites.

  • Evaluation of the Diameter Influence on the Tensile Strength of Pineapple Leaf Fibers (PALF) by Weibull Method
    Materials Research, 2015
    Co-Authors: Maria Carolina Andrade Teles, Frederico Muylaert Margem, Gabriel Oliveira Glória, Giulio Rodrigues Altoé, Pedro Amoy Netto, Fábio De Oliveira Braga, Sergio Neves Monteiro
    Abstract:

    The Fiber extracted from pineapple leaf (PALF) displays relevant mechanical properties that are motivating investigations for possible engineering application as polymer composite reinforcement. As any natural Lignocellulosic Fiber, the PALF presents non-uniform dimensions and heterogeneous properties with a significant dispersion of values. In fact, a marked variation in the tensile strength has been reported, which represents a problem for the design of a PALF reinforced composite. In several other Lignocellulosic Fibers, the diameter dimension was found to affect the value of the tensile strength. This work investigated the precise diameter dependence of the PALF tensile strength using the Weibull statistic method. The results showed a mathematical hyperbolic type of inverse correlation between the PALF strength and its diameter, which was found to be similar to that commonly obtained in other Lignocellulosic Fibers.

Cheng Hock Chuah - One of the best experts on this subject based on the ideXlab platform.

  • Applications of Lignocellulosic Fibers and Lignin in Bioplastics: A Review
    Polymers, 2019
    Co-Authors: Jianlei Yang, Yern Chee Ching, Cheng Hock Chuah
    Abstract:

    Lignocellulosic Fibers and lignin are two of the most important natural bioresources in the world. They show tremendous potential to decrease energy utilization/pollution and improve biodegradability by replacing synthetic Fibers in bioplastics. The compatibility between the Fiber-matrix plays an important part in the properties of the bioplastics. The improvement of Lignocellulosic Fiber properties by most surface treatments generally removes lignin. Due to the environmental pollution and high cost of cellulose modification, focus has been directed toward the use of Lignocellulosic Fibers in bioplastics. In addition, lignin-reinforced bioplastics are fabricated with varying success. These applications confirm there is no need to remove lignin from Lignocellulosic Fibers when preparing the bioplastics from a technical point of view. In this review, characterizations of Lignocellulosic Fibers and lignin related to their applications in bioplastics are covered. Then, we generalize the developments and problems of lignin-reinforced bioplastics and modification of lignin to improve the interaction of lignin-matrix. As for Lignocellulosic Fiber-reinforced bioplastics, we place importance on the low compatibility of the Lignocellulosic Fiber–matrix. The applications of lignin-containing cellulose and Lignocellulosic Fibers without delignification in the bioplastics are reviewed. A comparison between Lignocellulosic Fibers and lignin in the bioplastics is given.

Johnny Beaugrand - One of the best experts on this subject based on the ideXlab platform.

  • Lignocellulosic Fibers: a critical review of the extrusion process for enhancement of the properties of natural Fiber composites
    RSC Advances, 2017
    Co-Authors: Antoine Gallos, Florent Allais, Gabriel Paës, Johnny Beaugrand
    Abstract:

    Natural Fiber composites have various applications, since they can bring interesting mechanical and sustainability properties. Extrusion with a single-or twin-screw is the main industrial process to incorporate Lignocellulosic Fibers into polymers. In this review, the origin and preparation of Lignocellulosic Fibers are first presented, before discussing the composite processing, with a particular emphasis on the impact of process conditions on the composites final properties that is highly related to the final application. A broad panel of composites reinforced with Lignocellulosic Fibers is reviewed along with their polymeric matrix, Lignocellulosic Fiber type and pretreatments, and extrusion process conditions. Finally, the most critical extrusion process parameters (screw profile, speed and temperature) are also examined in order to determine some guidelines to optimize Lignocellulosic Fiber composites preparation.

  • Lignocellulosic Fiber breakage in a molten polymer. Part 1. Qualitative analysis using rheo-optical observations
    Composites Part A: Applied Science and Manufacturing, 2016
    Co-Authors: Romain Castellani, Erika Di Giuseppe, Sandrine Dobosz, Bruno Vergnes, Françoise Berzin, Johnny Beaugrand, Tatiana Budtova
    Abstract:

    Understanding how Lignocellulosic Fibers break during compounding and shaping processes (e.g. extrusion, injection) is of the greatest importance for mastering Fiber size evolution and thus predicting composite mechanical properties. In this first paper of a series devoted to this topic, rheo-optical experiments were used for a direct observation of Fibers’ behavior when sheared in a molten thermoplastic matrix. Fibers from four vegetal species were studied: hemp, flax, sisal and miscanthus. While possessing different morphological, composition and mechanical characteristics, these Fibers also display different preponderant breakage mechanisms. We were able to distinguish Fibers breakage (i) in a fragile way (flax and sisal), (ii) by fatigue, i.e. cumulated strain (hemp), or (iii) by peeling (miscanthus). Each Fiber type is qualitatively classified according to these categories and correlations with lignin and hemicellulose contents are discussed.

  • x ray computed microtomography and 2d image analysis for morphological characterization of short Lignocellulosic Fibers raw materials a benchmark survey
    Composites Part A-applied Science and Manufacturing, 2015
    Co-Authors: Seif Eddine Hamdi, Johnny Beaugrand, Christine Delisee, Jerome Malvestio, Nicolas Da Silva, Anne Le Duc
    Abstract:

    Abstract Optimizing the performance of Lignocellulosic Fibers often requires relating mechanical behavior or morphological characteristics to microstructure. X-ray computed microtomography (X-ray CT), which provides 3D images with a high level of detail at both the micro- and macro-scales, may overcome these difficulties. This work provides a comparative analysis of the potential of X-ray CT (3D) and an office scanner (2D) for morphological characterization of Lignocellulosic Fibers. To this end, three specimens of Lignocellulosic Fiber materials obtained after the first decortication of the plant were retained. X-ray CT and 2D scanning correlations of sample diameter distributions are presented. The general aspects of the Fibers diameter correlation are discussed. Image analysis was used to assess the potential and limitations of both the X-ray CT and 2D scanning methods based on the experimental work, and the main conclusions of the benchmark study are given in a table.

  • Lignocellulosic Fiber reinforced composites influence of compounding conditions on defibrization and mechanical properties
    Journal of Applied Polymer Science, 2013
    Co-Authors: Françoise Berzin, Johnny Beaugrand
    Abstract:

    This work describes a systematic study of the compounding conditions by twin-screw extrusion on the defibrization process that modulates the Fiber aspect ratio and in turn the mechanical properties. Composites made of polycaprolactone reinforced by 20% hemp Fibers were prepared by melt blending. The influence of the extrusion parameters (screw speed, feed rate, barrel temperature, and screw profile) and the initial Fiber moisture content on both the Fiber dimensions and the mechanical performance of the composite was investigated. The Fiber aspect ratio increased when the Fibers were water plasticized, principally at a higher feed rate and under a moder- ated extrusion temperature. The screw speed slightly influenced the Fiber dimensions. Flow modeling was used to estimate the specific mechanical energy provided to the Fibers, which ranged from 300 to 1700 kWh/t. Independent of the screw profile, a decrease in Fiber length with an increase in energy was observed. The evolution of the Fiber length and aspect ratios with respect to energy can be accu- rately described by an exponential function. V C 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 128: 1227-1238, 2013

  • Lignocellulosic Fiber reinforced composites: influence of compounding conditions on defibrization and mechanical properties
    Journal of Applied Polymer Science, 2013
    Co-Authors: Johnny Beaugrand, Françoise Berzin
    Abstract:

    This work describes a systematic study of the compounding conditions by twin-screw extrusion on the defibrization process that modulates the Fiber aspect ratio and in turn the mechanical properties. Composites made of polycaprolactone reinforced by 20% hemp Fibers were prepared by melt blending. The influence of the extrusion parameters (screw speed, feed rate, barrel temperature, and screw profile) and the initial Fiber moisture content on both the Fiber dimensions and the mechanical performance of the composite was investigated. The Fiber aspect ratio increased when the Fibers were water plasticized, principally at a higher feed rate and under a moderated extrusion temperature. The screw speed slightly influenced the Fiber dimensions. Flow modeling was used to estimate the specific mechanical energy provided to the Fibers, which ranged from 300 to 1700 kWh/t. Independent of the screw profile, a decrease in Fiber length with an increase in energy was observed. The evolution of the Fiber length and aspect ratios with respect to energy can be accurately described by an exponential function

Wenxi Cheng - One of the best experts on this subject based on the ideXlab platform.

  • preparation and properties of Lignocellulosic Fiber caco3 thermoplastic starch composites
    Carbohydrate Polymers, 2019
    Co-Authors: Wenxi Cheng
    Abstract:

    Abstract Lignocellulosic Fiber (LCF)/CaCO3 (CG)/thermoplastic starch (TPS) composites were prepared by blending LCF/CG hybrid (82/18, g/g) with glycerin and corn starch in different weight ratios (0/35/100, 27/35/100, 54/35/100 and 81/35/100, g/g/g) at 130℃, which were then characterized by rheology, XRD, SEM and DSC analysis, tensile test and soil burial test. When the dosage of LCF/CG was not more than 54 g, LCF and CG in LCF/CG/TPS composites were well dispersed, and the corresponding composites had better rheological properties. XRD results showed that the crystallinity of TPS in the presence of LCF/CG was significantly reduced after melt blending process, which caused by the inhibition effect of LCF on the crystallization of TPS. The tensile test results showed that the tensile strength, modulus and elongation at break of LCF/CG/TPS composite were better than those of pure TPS. Besides, due to the looser structures, LCF/CG/TPS composites biodegraded faster than pure TPS.

  • Preparation and properties of Lignocellulosic Fiber/CaCO3/thermoplastic starch composites.
    Carbohydrate polymers, 2019
    Co-Authors: Wenxi Cheng
    Abstract:

    Abstract Lignocellulosic Fiber (LCF)/CaCO3 (CG)/thermoplastic starch (TPS) composites were prepared by blending LCF/CG hybrid (82/18, g/g) with glycerin and corn starch in different weight ratios (0/35/100, 27/35/100, 54/35/100 and 81/35/100, g/g/g) at 130℃, which were then characterized by rheology, XRD, SEM and DSC analysis, tensile test and soil burial test. When the dosage of LCF/CG was not more than 54 g, LCF and CG in LCF/CG/TPS composites were well dispersed, and the corresponding composites had better rheological properties. XRD results showed that the crystallinity of TPS in the presence of LCF/CG was significantly reduced after melt blending process, which caused by the inhibition effect of LCF on the crystallization of TPS. The tensile test results showed that the tensile strength, modulus and elongation at break of LCF/CG/TPS composite were better than those of pure TPS. Besides, due to the looser structures, LCF/CG/TPS composites biodegraded faster than pure TPS.

J R M Dalmeida - One of the best experts on this subject based on the ideXlab platform.

  • creep behavior of Lignocellulosic Fiber polypropylene matrix composites
    Materials Science Forum, 2012
    Co-Authors: J R M Dalmeida, Anderson L L Da Silva
    Abstract:

    Lignocellulosic residues obtained after the sustainable harvesting of heart of palm from pejibaye (Bactris gasipaes) palms were managed to produce chopped Fibers. These Fibers can be used to manufacture agglomerated panels and also as reinforcement in polymer-matrix composites. Polypropylene (PP) is a convenient polymer to be loaded with these residues due to its large applications, including under-the-bonnet applications by the automotive industry. PP-pejibaye composites with 10wt% of Fiber mass fraction were manufactured and their creep behavior was studied. The experimental results were suitably described analyzing the variation of the creep modulus fitting the experimental data points to the three-element model where the Kelvin-Voigt element is attached to an independent spring. The results obtained show that the incorporation of the chopped pejibaye Fibers to not affect the creep performance of the composite. This behavior is very promising, since untreated Fibers were used, meaning that the use of expensive and many times environmentally detrimental Fiber surface chemical treatments can be avoided.

  • effect of drying molding pressure and strain rate on the flexural mechanical behavior of piassava attalea funifera mart Fiber polyester composites
    Polymer Testing, 2005
    Co-Authors: J F De Deus, Sergio Neves Monteiro, J R M Dalmeida
    Abstract:

    The flexural strength of piassava-polyester composites was evaluated as a function of the molding force, strain rate and drying condition of the Fibers. Composites with as-received Fibers and with pre-dried Fibers were fabricated, with mass fraction of Fibers ranging from 0.20 to 0.40. The pre-drying of the Fibers was shown to be the most relevant variable. Reduction of absorbed water before the incorporation of the Fibers to the polyester matrix strongly affected the wetting of the Fiber by the polymeric matrix, enhancing the Fiber to matrix interaction. The composites manufactured with the pre-dried Fibers show better flexural strength. Their behavior was independent of the molding pressure. The flexural strength of the composites decreased with the increase of the strain rate, but only minor variations were measured under the range of strain rates analyzed. The composites with the higher Fiber loading, and pre-dried Fibers, showed flexural strength values similar to the higher values reported for other Lignocellulosic Fiber-reinforced composites.

  • analysis of the tensile strength of polyester hybrid ramie cotton fabric composites
    Polymer Testing, 2004
    Co-Authors: C Z Paiva, Sergio Neves Monteiro, L H De Carvalho, V M Fonseca, J R M Dalmeida
    Abstract:

    Abstract Plain weave hybrid ramie–cotton fabrics were used as reinforcement in polyester matrix composites. The tensile strength of the composites was determined as a function of the volume fraction and orientation of the ramie Fibers. Composites were tensile tested with ramie Fibers oriented parallel, (0), to the tensile axis and with various stacking sequence configurations (0/90). The results obtained showed that the main parameter governing the tensile properties of the composites was the ramie volume fraction parallel to the direction of the tensile axis. The contribution of the cotton Fibers was shown to be minimal. Indeed, the results obtained for the tensile strength of the (0) composites were shown to follow a common rule of mixtures law, disregarding the contribution of the cotton Fibers. Values of tensile strength of up to 338% greater than that of the matrix were obtained which shows the potential of the ramie Fiber as reinforcement in Lignocellulosic Fiber composites.