Steam Explosion Impact to Technical Hemp Fiber Diameter

Microfibers and nanofibers from natural products have high mechanical properties. For this reason researchers pay particular attention to the natural fibers and to the method how they are obtained. In the research samples with different treatments (alkaline pretreatment, steam explosion and water extraction) were investigated to evaluate treatment influence on fiber diameters. Fractionation does not provide actual results of fibers diameter as thinner fibers agglomerate to each other and around thicker fibers and cannot be sieved. Fiber diameter measurement with an optical microscope shows that pretreatment and treatment reduced the thickest fiber percentage and increase the number of fine particles. Dew-retted hemp gives 16% of thicker fibers and only 39% fibers with a diameters less than 63µm. 50% of alkaline pretreated and steam explosion treated fibers diameters are less than 63 µm and only 8% of diameters fall in range 160 - 630 µm.

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Development and Characterization of Environmentally Friendly Wood Plastic Composites from Biobased Polyethylene and Short Natural Fibers Processed by Injection Moulding

Polymers ◽

10.3390/polym13111692 ◽

2021 ◽

Vol 13 (11) ◽

pp. 1692

Author(s):

Celia Dolza ◽

Eduardo Fages ◽

Eloi Gonga ◽

Jaume Gomez-Caturla ◽

Rafael Balart ◽

...

Keyword(s):

Mechanical Properties ◽

Polymer Matrix ◽

Fire Behavior ◽

Natural Fibers ◽

Environmentally Friendly ◽

Extrusion Process ◽

Hemp Fiber ◽

Wood Plastic Composites ◽

Lignocellulosic Fibers ◽

Plastic Composites

Environmentally friendly wood plastic composites (WPC) with biobased high density polyethylene (BioHDPE) as the polymer matrix and hemp, flax and jute short fibers as natural reinforcements, were melt-compounded using twin-screw extrusion and shaped into pieces by injection molding. Polyethylene-graft-maleic anhydride (PE-g-MA) was added at two parts per hundred resin to the WPC during the extrusion process in order to reduce the lack in compatibility between the lignocellulosic fibers and the non-polar polymer matrix. The results revealed a remarkable improvement of the mechanical properties with the combination of natural fibers, along with PE-g-MA, highly improved stiffness and mechanical properties of neat BioHDPE. Particularly, hemp fiber drastically increased the Young’s modulus and impact strength of BioHDPE. Thermal analysis revealed a slight improvement in thermal stability with the addition of the three lignocellulosic fibers, increasing both melting and degradation temperatures. The incorporation of the fibers also increased water absorption due to their lignocellulosic nature, which drastically improved the polarity of the composite. Finally, fire behavior properties were also improved in terms of flame duration, thanks to the ability of the fibers to form char protective barriers that isolate the material from oxygen and volatiles.

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Serat Pelepah Sagu Sebagai Alternatif Pengganti Serat Sintesis Fiberglass

PENA TEKNIK: Jurnal Ilmiah Ilmu-Ilmu Teknik ◽

10.51557/pt_jiit.v6i1.631 ◽

2021 ◽

Vol 6 (1) ◽

pp. 14

Author(s):

Budiawan Sulaeman ◽

Rakhmawati Natsir

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Composite Material ◽

Glass Fiber ◽

Fiber Diameter ◽

Natural Fibers ◽

Fiber Volume ◽

Synthetic Fibers ◽

Matrix Volume ◽

Naoh Solution

Tujuan penelitian ini untuk menganalisis pengaruh ukuran besar diameter serat pelepah sagu terhadap sifat mekanik kekuatan tarik, menganalisis sifat mekanik tarik material komposit yang diperkuat serat pelepah sagu.Berdasarkan hasil penelitian; (1). Larutan NAoH berpengaruh terhadap kuat Tarik specimen, hal ini ditunjukkan pada 2,5% (NAoH terhadap H2O). Nilai kekuatan tariknya 49,486 N/mm2. (2). Serat pelepah sagu kuat tariknya jauh dibawah serat gelas. (48,435 N/mm2< 323 N/mm2). Hal ini disebabkan rongga yang terdapat di serat sintesis lebih rapat dibanding serat alami. (3). Berdasarkan variabel yang diteliti, kekuatan tarik (Ftu) dengan nilai tertinggi terjadi pada komposit (volume 85% matriks : 15% serat) yaitu sebesar 3,12 beban 11824 N. (4). Kekuatan tarik mengalami kenaikan terhadap peningkatan komposisi volume serat. (5). Spesimen uji yang mengalami regangan dan patah pada titik load yaitu pada komposisi volume 85% matriks : 15% serat sebesar 3,12 MPa dengan regangan sebesar 8% dan modulus young yang terjadi sebesar 38,615 MPa.The purpose of this study was to analyze the effect of the size of the sago frond fiber diameter on the mechanical properties of the tensile strength, to analyze the tensile mechanical properties of the composite material reinforced by sago frond fibers. Based on research results; (1) NaOH solution affects the tensile strength of the specimen. This is shown at 2.5% (NaOH to H2O), the tensile strength value is 49.486 N/mm2. (2) Sago frond fiber has a tensile strength far below the glass fiber (48,435 N/mm2 <323 N/mm2). This is because the cavities in synthetic fibers are denser than natural fibers. (3) Based on the variables studied, the tensile strength (Ftu) with the highest value occurs in the composite (85% matrix volume: 15% fiber), which is 3.12 load 11824 N. (4) Tensile strength increases with the increase in fiber volume composition. (5) The test specimens that experienced a strain and fracture at the load point, namely the composition of volume 85% matrix: 15% fiber was 3.12 MPa with a strain of 8% and the modulus young that occurred was 38.615 MPa.

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Faculty Opinions recommendation of Electrospun matrices for pelvic floor repair: effect of fiber diameter on mechanical properties and cell behavior.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.726781354.793560587 ◽

2019 ◽

Author(s):

Christopher Chapple

Keyword(s):

Mechanical Properties ◽

Pelvic Floor ◽

Fiber Diameter ◽

Cell Behavior ◽

Pelvic Floor Repair

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Average fiber diameter measurement in Scanning Electron Microscopy images based on Gabor filtering and Hough transform

Measurement ◽

10.1016/j.measurement.2019.04.051 ◽

2019 ◽

Vol 141 ◽

pp. 364-370 ◽

Cited By ~ 3

Author(s):

Sahar Babashakoori ◽

Mehdi Ezoji

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Hough Transform ◽

Fiber Diameter ◽

Average Fiber Diameter ◽

Diameter Measurement ◽

Gabor Filtering ◽

Microscopy Images ◽

Scanning Electron

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Experimental Analysis of the Mechanical Properties and Resistivity of Tectonic Coal Samples with Different Particle Sizes

Energies ◽

10.3390/en14082303 ◽

2021 ◽

Vol 14 (8) ◽

pp. 2303

Author(s):

Congyu Zhong ◽

Liwen Cao ◽

Jishi Geng ◽

Zhihao Jiang ◽

Shuai Zhang

Keyword(s):

Mechanical Properties ◽

Particle Size ◽

Compressive Strength ◽

Elastic Modulus ◽

Uniaxial Compressive Strength ◽

Coalbed Methane ◽

Coal Sample ◽

Fine Particles ◽

Particle Sizes ◽

Tectonic Coal

Because of its weak cementation and abundant pores and cracks, it is difficult to obtain suitable samples of tectonic coal to test its mechanical properties. Therefore, the research and development of coalbed methane drilling and mining technology are restricted. In this study, tectonic coal samples are remodeled with different particle sizes to test the mechanical parameters and loading resistivity. The research results show that the particle size and gradation of tectonic coal significantly impact its uniaxial compressive strength and elastic modulus and affect changes in resistivity. As the converted particle size increases, the uniaxial compressive strength and elastic modulus decrease first and then tend to remain unchanged. The strength of the single-particle gradation coal sample decreases from 0.867 to 0.433 MPa and the elastic modulus decreases from 59.28 to 41.63 MPa with increasing particle size. The change in resistivity of the coal sample increases with increasing particle size, and the degree of resistivity variation decreases during the coal sample failure stage. In composite-particle gradation, the proportion of fine particles in the tectonic coal sample increases from 33% to 80%. Its strength and elastic modulus increase from 0.996 to 1.31 MPa and 83.96 to 125.4 MPa, respectively, and the resistivity change degree decreases. The proportion of medium particles or coarse particles increases, and the sample strength, elastic modulus, and resistivity changes all decrease.

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Mechanical Properties of Mortars Reinforced with Amazon Rainforest Natural Fibers

Materials ◽

10.3390/ma14010155 ◽

2020 ◽

Vol 14 (1) ◽

pp. 155

Author(s):

Régis Pamponet da Fonseca ◽

Janaíde Cavalcante Rocha ◽

Malik Cheriaf

Keyword(s):

Mechanical Properties ◽

Flexural Strength ◽

Natural Fibers ◽

Construction Materials ◽

Hot Water ◽

Amazon Rainforest ◽

Hot Water Treatment ◽

Composite Binder ◽

Naoh Solution ◽

Reference Samples

The addition of natural fibers used as reinforcement has great appeal in the construction materials industry since natural fibers are cheaper, biodegradable, and easily available. In this work, we analyzed the feasibility of using the fibers of piassava, tucum palm, razor grass, and jute from the Amazon rainforest as reinforcement in mortars, exploiting the mechanical properties of compressive and flexural strength of samples with 1.5%, 3.0%, and 4.5% mass addition of the composite binder (50% Portland cement + 40% metakaolin + 10% fly ash). The mortars were reinforced with untreated (natural) and treated (hot water treatment, hornification, 8% NaOH solution, and hybridization) fibers, submitted to two types of curing (submerged in water, and inflated with CO2 in a pressurized autoclave) for 28 days. Mortars without fibers were used as a reference. For the durability study, the samples were submitted to 20 drying/wetting cycles. The fibers improved the flexural strength of the mortars and prevented the abrupt rupture of the samples, in contrast to the fragile behavior of the reference samples. The autoclave cure increased the compressive strength of the piassava and tucum palm samples with 4.5% of fibers.

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Effects of Different Types of Fibers on the Physical and Mechanical Properties of MICP-Treated Calcareous Sand

Materials ◽

10.3390/ma14020268 ◽

2021 ◽

Vol 14 (2) ◽

pp. 268

Author(s):

Jitong Zhao ◽

Huawei Tong ◽

Yi Shan ◽

Jie Yuan ◽

Qiuwang Peng ◽

...

Keyword(s):

Mechanical Properties ◽

Water Absorption ◽

Glass Fiber ◽

Physical And Mechanical Properties ◽

Polyester Fiber ◽

Engineering Properties ◽

Fiber Types ◽

Calcite Precipitation ◽

Calcareous Sand ◽

Hemp Fiber

Microbial-induced calcite precipitation (MICP) has been a promising method to improve geotechnical engineering properties through the precipitation of calcium carbonate (CaCO3) on the contact and surface of soil particles in recent years. In the present experiment, water absorption and unconfined compressive strength (UCS) tests were carried out to investigate the effects of three different fiber types (glass fiber, polyester fiber, and hemp fiber) on the physical and mechanical properties of MICP-treated calcareous sand. The fibers used were at 0%, 0.10%, 0.15%, 0.20%, 0.25%, 0.30%, 0.35%, and 0.40% relative to the weight of the sand. The results showed that the failure strain and ductility of the samples could be improved by adding fibers. Compared to biocemented sand (BS), the water absorption of these three fiber-reinforced biocemented sands were, respectively, decreased by 11.60%, 21.18%, and 7.29%. UCS was, respectively, increased by 24.20%, 60.76%, and 6.40%. Polyester fiber produced the best effect, followed by glass fiber and hemp fiber. The optimum contents of glass fiber and polyester fiber were 0.20% and 0.25%, respectively. The optimum content of hemp fiber was within the range of 0.20–0.25%. Light-emitting diode (LED) microscope and scanning electron microscope (SEM) images lead to the conclusion that only a little calcite precipitation had occurred around the hemp fiber, leading to a poor bonding effect compared to the glass and polyester fibers. It was therefore suggested that polyester fiber should be used to improve the properties of biocemented sand.

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The Structure and Mechanical Properties of Hemp Fibers-Reinforced Poly(ε-Caprolactone) Composites Modified by Electron Beam Irradiation

Applied Sciences ◽

10.3390/app11125317 ◽

2021 ◽

Vol 11 (12) ◽

pp. 5317

Author(s):

Rafał Malinowski ◽

Aneta Raszkowska-Kaczor ◽

Krzysztof Moraczewski ◽

Wojciech Głuszewski ◽

Volodymyr Krasinskyi ◽

...

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Electron Beam ◽

Impact Strength ◽

Flexural Modulus ◽

Natural Fibers ◽

High Energy ◽

Electron Radiation ◽

Elongation At Break ◽

Hemp Fibers

The need for the development of new biodegradable materials and modification of the properties the current ones possess has essentially increased in recent years. The aim of this study was the comparison of changes occurring in poly(ε-caprolactone) (PCL) due to its modification by high-energy electron beam derived from a linear electron accelerator, as well as the addition of natural fibers in the form of cut hemp fibers. Changes to the fibers structure in the obtained composites and the geometrical surface structure of sample fractures with the use of scanning electron microscopy were investigated. Moreover, the mechanical properties were examined, including tensile strength, elongation at break, flexural modulus and impact strength of the modified PCL. It was found that PCL, modified with hemp fibers and/or electron radiation, exhibited enhanced flexural modulus but the elongation at break and impact strength decreased. Depending on the electron radiation dose and the hemp fibers content, tensile strength decreased or increased. It was also found that hemp fibers caused greater changes to the mechanical properties of PCL than electron radiation. The prepared composites exhibited uniform distribution of the dispersed phase in the polymer matrix and adequate adhesion at the interface between the two components.

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Microstructural Characterization and Mechanical Properties of Ti-6Al-4V Alloy Subjected to Dynamic Plastic Deformation Achieved by Multipass Hammer Forging with Different Forging Temperatures

Advances in Materials Science and Engineering ◽

10.1155/2019/6410238 ◽

2019 ◽

Vol 2019 ◽

pp. 1-12 ◽

Cited By ~ 2

Author(s):

Xiurong Fang ◽

Jiang Wu ◽

Xue Ou ◽

Fuqiang Yang

Keyword(s):

Mechanical Properties ◽

Plastic Deformation ◽

Volume Fraction ◽

Microstructural Characterization ◽

Optical Microscope ◽

Strain Rates ◽

Materials Properties ◽

Forging Process ◽

Hammer Forging ◽

Dynamic Plastic Deformation

Dynamic plastic deformation (DPD) achieved by multipass hammer forging is one of the most important metal forming operations to create the excellent materials properties. By using the integrated approaches of optical microscope and scanning electron microscope, the forging temperature effects on the multipass hammer forging process and the forged properties of Ti-6Al-4V alloy were evaluated and the forging samples were controlled with a total height reduction of 50% by multipass strikes from 925°C to 1025°C. The results indicate that the forging temperature has a significant effect on morphology and the volume fraction of primary α phase, and the microstructural homogeneity is enhanced after multipass hammer forging. The alloy slip possibility and strain rates could be improved by multipass strikes, but the marginal efficiency decreases with the increased forging temperature. Besides, a forging process with an initial forging temperature a bit above β transformation and finishing the forging a little below the β transformation is suggested to balance the forging deformation resistance and forged mechanical properties.

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Valorization of Invasive Plants from Macaronesia as Filler Materials in the Production of Natural Fiber Composites by Rotational Molding

Polymers ◽

10.3390/polym13132220 ◽

2021 ◽

Vol 13 (13) ◽

pp. 2220

Author(s):

Zaida Ortega ◽

Francisco Romero ◽

Rubén Paz ◽

Luis Suárez ◽

Antonio Nizardo Benítez ◽

...

Keyword(s):

Mechanical Properties ◽

Invasive Plant ◽

Natural Fiber ◽

Ricinus Communis ◽

Local Level ◽

Natural Fibers ◽

Fiber Composites ◽

Filler Materials ◽

Natural Fiber Composites ◽

Rotational Molding

This paper compares the mechanical properties of different natural fiber composites produced by rotational molding as a way of waste valorization from campaigns to control invasive plant species in Macaronesia. Rotomolded parts produced with polymeric matrices (polyethylene) and filled with up to 20% by weight of cellulosic fibers obtained from Arundo donax L., Pennisetum setaceum, and Ricinus communis plants were characterized in terms of tensile, flexural, and impact strength. It was found that the sieving of natural fibers allowed for their introduction in higher loadings, from 10 (for un-sieved material) to 20%; fiber size greatly affected the mechanical properties of the final parts, although some combinations were proven not to reduce the mechanical properties of the neat resin. This study is a first approach to the valorization of residues obtained from periodic campaigns of the control of invasive species performed by public authorities, usually at the local level. It is important to highlight that the main objective of this research did not focus on economically profitable activity; instead, it was focused on the reduction of wastes to be disposed from ecosystem maintenance actions and the investment of potential income into preservation policies.

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