Single Fiber Strength Research Articles

Absence of the Z-disc protein α-actinin-3 impairs the mechanical stability of Actn3KO mouse fast-twitch muscle fibres without altering their contractile properties or twitch kinetics

BackgroundA common polymorphism (R577X) in the ACTN3 gene results in the complete absence of the Z-disc protein α-actinin-3 from fast-twitch muscle fibres in ~ 16% of the world’s population. This single gene polymorphism has been subject to strong positive selection pressure during recent human evolution. Previously, using an Actn3KO mouse model, we have shown in fast-twitch muscles, eccentric contractions at L0 + 20% stretch did not cause eccentric damage. In contrast, L0 + 30% stretch produced a significant ~ 40% deficit in maximum force; here, we use isolated single fast-twitch skeletal muscle fibres from the Actn3KO mouse to investigate the mechanism underlying this.MethodsSingle fast-twitch fibres are separated from the intact muscle by a collagenase digest procedure. We use label-free second harmonic generation (SHG) imaging, ultra-fast video microscopy and skinned fibre measurements from our MyoRobot automated biomechatronics system to study the morphology, visco-elasticity, force production and mechanical strength of single fibres from the Actn3KO mouse. Data are presented as means ± SD and tested for significance using ANOVA.ResultsWe show that the absence of α-actinin-3 does not affect the visco-elastic properties or myofibrillar force production. Eccentric contractions demonstrated that chemically skinned Actn3KO fibres are mechanically weaker being prone to breakage when eccentrically stretched. Furthermore, SHG images reveal disruptions in the myofibrillar alignment of Actn3KO fast-twitch fibres with an increase in Y-shaped myofibrillar branching.ConclusionsThe absence of α-actinin-3 from the Z-disc in fast-twitch fibres disrupts the organisation of the myofibrillar proteins, leading to structural weakness. This provides a mechanistic explanation for our earlier findings that in vitro intact Actn3KO fast-twitch muscles are significantly damaged by L0 + 30%, but not L0 + 20%, eccentric contraction strains. Our study also provides a possible mechanistic explanation as to why α-actinin-3-deficient humans have been reported to have a faster decline in muscle function with increasing age, that is, as sarcopenia reduces muscle mass and force output, the eccentric stress on the remaining functional α-actinin-3 deficient fibres will be increased, resulting in fibre breakages.

Banana Fiber Degumming by Alkali Treatment and Ultrasonic Methods

ABSTRACT This study focused on reducing the burden of air pollution, wastage of banana pseudostems, and adding value to the plant’s products. Alkali pre-treatment and ultrasounds aided in degumming banana fiber to remove wax, lignin, hemicellulose, and other unwanted extractives. The chemical analysis method revealed 72.78% cellulosic content in ultra-sonicated fiber. Ultra-sonication attained an average diameter of 19.36 μm compared to 49.94 μm of alkali pre-treated fiber and 171.87 μm of untreated fiber as observed through the digital optical microscope. Scanning Electron Microscopy (SEM) showed well-separated fibrils of ultra-sonicated fiber. X-Ray Photoelectron Spectroscopy (XPS) showed de-convoluted peaks of C1s, O1s, and N1s that confirmed lignin removal. Transform Infra-Red (ATR-FTIR) Spectrometer revealed varnishing peak bands of C − O and C═O functional groups between 1600 cm−1 and 1733 cm−1 related to lignin and hemicelluloses. The X-ray Diffractometer (XRD) showed improved crystallinity up to 63.29%. The single fiber strength testing machine showed optimized breaking strength of 31.12cN/dtex and breakage elongation of 9.38%. The chemical, mechanical and morphological properties showed great promise for high-quality banana fibers.

Tensile strength of single banana fibers (SBFs) improved by novel alkaline treatment

Environmental concern on global warming controversy has raised the issue that forced the researchers to work on green materials. Among them, plant fibers are recognized as environmentally friendly with a high potential to explore their adaptability and utilization for many engineering applications. This paper aims to examine the banana fiber behavior of various alkaline treatment conditions and compare the results with untreated fiber conducted on the same tests. Both the tests were subjected to physical and tensile load, then each condition was tested individually to achieve a valid average. The Paper frame technique was adopted for this single fiber tensile test (SFTT) and corresponding to the stress-strain curves. Surface morphology was done using scanning electron microscopy (SEM) to compare and find the effect of alkaline treatment on surface fiber modification.

In-situ compatibilized starch/polyacylonitrile composite fiber fabricated via dry-wet spinning technique

An in-situ compatibilized starch (St) and polyacrylonitrile (PAN) composite spinning solution was designed by preparing starch-graft-polyacrylonitrile (St-g-PAN) through graft copolymerizing acrylonitrile from soluble starch and using ammonium cerium nitrate (CAN) as initiator. As dimethyl sulfoxide (DMSO) was used as the solvent, St/St-g-PAN/PAN/DMSO spinning solution was prepared and St/St-g-PAN/PAN composite fibers were obtained by dry-wet spinning technique. The effects of air gap, coagulation bath, hot drawing and stretching, and thermal-setting process were studied in detail. Fourier transform infrared spectroscopy (FT-IR), solid state nuclear magnetic resonance (13C NMR), thermogravimetric analysis (TGA), X-ray diffraction analysis (XRD), and scanning electron microscopy (SEM) were used to characterize the structure and morphology of the copolymer and the fibers. Single fiber strength tester and sonic orientation instrument were performed to measure the fiber mechanical properties and orientation degrees. The results showed that as the grafting ratio ~150.0% and the reacting mixture containing St ~9.8%, St-g-PAN ~81.6%, and homo-PAN ~8.6% in DMSO solution with 6.0 wt% in concentration were used, the spinning parameters such as air gap ~35 mm, coagulation bath concentration ~70%, temperature ~25 °C, and positive stretching ~48%, hot drawing and stretching 6 times at 80 °C, thermal-setting at 90 °C for 3 h under constant length mode were met, composite fibers with breaking strength 3.41 cN·dtex−1, breaking elongation 14.41%, sonic orientation factor 0.625, moisture recovery ratio 10.53% under standard condition (1 atm, 22 °C, and relative humidity 65%), and boiling water shrinkage ratio 9.60% were obtained. The as prepared composite fiber was better than common viscose fiber 2.11 cN·dtex−1 and cotton fiber ~3.24 cN·dtex−1 and expected to be used in the fields of medical gauze, bandage, protective clothing, et al. besides of common textiles. The in-situ compatibilization method can be applied in preparation of other composite polymer materials.

Interfacial and Interlaminar Shear Strength of Unidirectional Viscose Fibre-Reinforced Epoxy Composites—an Overview of the Comparability of Results Obtained by Different Test Methods

In this study, the apparent interfacial and interlaminar shear strength (IFSS and ILSS) of single fibres and unidirectional (UD) viscose fibre-reinforced epoxy composites were characterised using different test methods. Microbond and pull-out tests were used to analyse the IFSS of single fibres embedded in epoxy and the transverse tensile test was applied to measure the IFSS of UD fibre-reinforced composites. The short beam shear test, single edge notched bending test (SENB), double-notched tensile test and double-notched compression test were applied to characterise the ILSS. The composites were produced from continuous tows with fibre mass fractions of 20%, 30% and 40% and fibres of different fineness (1.7, 3.3 and 28.0 dtex). The results showed that the different test procedures led to different trends of ILSS depending on the fibre mass fraction and fibre fineness used. The transverse tensile test revealed that the IFSS decreased with increasing fibre mass fraction and fibre diameter. A different trend was found with the short beam shear test and the SENB test for the ILSS. Here, higher values were detected with increasing fibre mass content, and the influence of the fineness was less noticeable. The double-notched shear tests (tensile and compression) showed a different trend: the ILSS increased with increasing fibre mass fraction from 20% to 30%. With a further increase to 40%, the ILSS tend to decrease slightly. An influence of the fibre fineness on the ILSS could not be statistically proven. The different trends of the test methods are attributed to the constitution of the composite and the different load application caused by the test procedures.

The Effect of Alkali Treatment and Addition of Microcrystalline Cellulose (MCC) on Physical and Tensile Properties of Ramie/Polyester Laminated Composites

The aim of this research is to investigate the effect of alkali treatment of ramie fibers and addition of MCC on the properties of ramie/polyester laminated composites. The alkali treatment was performed using NaOH solution at a room temperature. The laminated composites was manufactured using a vacuum infusion method for three layers of treated woven ramie fibers in the polyester matrix. The MCC (microcrystalline cellulose) powder 0.5 wt.% was added into the polyester resin and then mixed by a mechanical stirrer at a rotation speed of 350 rpm for 5 minutes. The physical characterization was evaluated using FTIR, XRD, and SEM methods. The tensile test of a single fiber and laminated composites was carried out according to the ASTM D3379 and ASTM D3039, respectively. The experimental results show that the XRD of treated fiber with 5 wt.% NaOH solution has the highest crystallinity index of 66.3%. It impacts the increase of tensile strength and elastic modulus of single ramie fiber by 18% and 55%, respectively. The addition of MCC into the polyester matrix of laminated composite can increase the tensile strength and elastic modulus by 18% and 21%, respectively, compared to the untreated laminated composite. In addition, the treated fibers laminated composite can improve the adhesion and chemical bonding between fibers and polyester as a matrix. The addition of MCC filler may prevent the initial propagation of cracks on interlaminar surfaces of laminated composite.

Surface modification of recycled coir fibers with hybrid coating and its effect on the properties of ABS composites

In this work, a hybrid coating (TSMA) was produced using tetraethyl orthosilicate (TEOS)/KH550/Styrene maleic anhydride copolymer (SMA) as raw materials. The coating was afterwards applied to modify recycled coir (r-coir) fibers via dip-coating. R-coir fibers reinforced ABS composites were then prepared and the reinforcing effect of fibers on the composite structure was investigated, as well. The r-coir fibers coated with TSMA were hydrolyzed in air for 3 days. The SiO2 particles produced by sol-gel reaction of TEOS were used to connect KH550 and SMA to the surface of the fibers and form an organic-inorganic ‘armor’ structure. The successful surface modification of the r-coir fibers was proved via FTIR spectroscopic study and the improvement of their decomposition temperature was evidenced by TGA. Furthermore, the homogeneous dispersion of TSMA on the surface of r-coir fibers was observed via SEM. In addition, the tensile strength of single fibers was found to increase by 36.1%. According to the results, TSMA can be successfully homogenized on the fiber surface, enabling one to repair the damaged areas and improve the tensile strength of single fibers. Besides, good compatibility between r-coir fibers and ABS was revealed by contact angle measurements. Furthermore, the bending strength and elastic modulus of TSMA-modified r-coir fibers/ABS composites were improved by 6% and 27%, respectively. Therefore, the method of plant fiber modification proposed in present work provides a reliable way for effective reuse of r-coir fibers.

Experimental study of physical, chemical and mechanical properties of enset and sisal fibers

The properties of composites depend on type and properties of the fiber, fiber structure and treatment. In this study, effects of NaOH treatment on the physical, chemical and mechanical properties of fibers collected from South-West Ethiopia were investigated using untreated, 5% and 10% alkali treated enset and sisal fibers. The effects of NaOH on diameter, moisture absorption, density, lignin and hemicellulose was experimentally studied. In addition, tenacity of both fibers was investigated by using optical microscopy, Fourier transform infrared spectroscopy and single fibers tensile strength tester. The 5% and 10% NaOH treatment significantly improved the moisture absorption and diameters. The moisture absorption of 5% and 10% NaOH treated enset fibers improved by 33% and 34%, while the same treatment on sisal fibers improved the moisture absorption by 30% and 40% respectively. The 5% NaOH treated enset and sisal fiber showed better tenacity, which is an indication of the tensile strength of single fiber, than untreated and 10% NaOH treated fibers. Improving moisture content, diameter, lignin and hemicellulose contents of the fibers contributes to better bonding as interlock with the matrix materials enhancing the mechanical properties of composites.

Study on carrier dyeing for high strength high modulus PVA fiber

High strength high modulus PVA fiber or PVA high-fiber has excellent performances, such as high strength, high modulus, heat resistance, corrosion resistance, UV resistance, excellent impact resistance and adhesion. With the expansion of the application range of PVA high-fiber and the demand for color, it is pressing to study on the dyeing of PVA high-fiber. In this paper, dyeing process on PVA high-fiber had been deeply researched. PVA high-fiber has compact structure and high crystallinity, so carrier dyeing was selected here. Meanwhile, the types of dyes (Direct dyes, Reactive dyes, Cationic dyes, Disperse dyes) and carriers (type: anion, amphoteric ion, non-ion), the carrier concentration, the dyeing temperature and dyeing holding time were all selected and optimized. In the end, the most suitable dye, the most suitable carrier and the most optimal dyeing process were all identified. It was found that Direct dyes were the most suitable for PVA high-fiber dyeing, and non-ionic carrier had the most obvious dyeing effect. Under Direct dye and carrier N-25 conditions, the dye uptake was higher up to 68.6%, and wash fastness could reach grade 4. In addition, the optimal pretreatment time and power of low temperature plasma was identified. However, it was found that the pretreatment was little effective to promote PVA fiber dyeing. Considering that the carrier may reduce PVA high-fiber performance, x-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), single fiber strength test were used. Finally it was concluded that the break strength of the dyed PVA high-fiber was slightly decreased and the crystal structure was barely changed.

Tensile Strength and Fracture Behavior of Single Abaca Fiber

ABSTRACT A novel experiment device was employed to investigate the tensile strength and fracture mechanism of single abaca fibers. Twenty specimens of untreated single fibers with a gauge length of 30 mm were subjected to tensile force with a loading rate of 0.46 N/s. Results show that the tensile strength of the fiber ranges from 417 MPa to 1548 MPa. The tensile strength was calculated using the measured value of cross-sectional area of each fiber, evaluated by using a three-dimensional microscopic observation. The observation conducted for all specimens reveals the fracture mechanism of the single fiber classified into three types, i.e. shear, tension, and combined of shear and tension. The considerably high tensile strength of the single fiber and fracture mechanism of the single fiber provide a possibility for designing high strength abaca fiber reinforced composite for various engineering applications.

Fabrication, microstructural and mechanical properties of arecanut leaf sheath fibre reinforced polyester resin composites

Arecanut leaf sheath (ANLS) an unexplored agricultural biomass is used to recover long staple lignocellulosic fibers. A long staple lignocellulosic fiber is extracted from ANLS biomass using 8% NaOH treatment. As reinforcing material ANLS fibre properties such as fibre length, diameter, moisture content, single fibre strength and X-ray diffraction analysis were carried out. Three types of composites, 15, 20 and 25 (w/w)% fibre loading composites have been prepared in unsaturated polyester resin matrix. The tensile, flexural and interlaminar shear strength (ILSS) properties and void content of these composites are studied. The tensile fracture behaviors of fibre and composites are studied with the help of scanning electron micrographs.

Study on polysaccharide polyelectrolyte complex and fabrication of alginate/chitosan derivative composite fibers

Sodium alginate (SA) blending with quaternary ammonium chitosan (QAC) polysaccharide polyelectrolyte complex (PEC) system was chosen to research the binary blending of anionic and cationic polyelectrolytes in detail and to fabricate SA/QAC composite fibers. The potential charge and the rheology of the PEC solution were characterized through Zeta Laser Particle Size Analyzer and DV-C Rotary Rheometer, the structure and properties of the composite fiber were examined by FT-IR, XRD, SEM, EDS, and YG004 single fiber strength meter. The results showed that as the mass ratio of SA to QAC increased from 0/1 to 10/1, the state of the binary solution in water changed from transparent uniform solution to turbid solution with flocculent precipitate, then back to uniform solution, accompanied by the electrical potential change. Moreover, the electrical potential also depended on salt in solution. By using this uniform PEC solution with the mass ratio of SA to QAC 10/1 and concentration 5.5 wt% in water, SA/QAC composite fibers with excellent performances of breaking strength 2.37 cN·dtex−1 and breaking elongation 14.11%, good antibacterial and hydrophobic properties were fabricated via green wet-spinning process. The FT-IR and EDS determination indicated there formed egg-box between SA and Ca2+, cross-linked network between glutaraldehyde(GA) and SA, QAC, respectively. Depending on its mechanical, natural, and antibacterial properties, the SA/QAC composite fiber has advantages in wound dressing, medical gauze, medical absorbable suture, and tissue engineering.

Thermal properties of natural fibres extracted from Palmyra sprouts

Effect of fibre extraction from Palmyra sprouts by manual method and water retting process has been studied. Mechanical and chemical properties of the fibres have been studied. Cellulose, lignin, ash and wax contents present in both manual and water retted palmyra sprout fibre are found to be 61.72% & 55.63%, 23.25 % & 30.66%, 5.15 % & 3.61 % and 0.66% & 0.84% respectively. The low composition of ash provides light-weight and stiffness to the fibres. Thermogravimetric analysis shows that the residual mass of water retted fibre shows is 26.77% at 498.2ºC and that of manual retted fibre is 21.31% at 498.2ºC. The average single fibre strength values for the water and manual retted samples are 2.34 N and 4 N respectively, with a standard deviation of 0.642 N and 1.81 N respectively. In this study, thermal properties are also analyzed.

Ekstrakcija i karakterizacija prirodnih vlakana Elettaria Cardamomum

Natural fibres are one of the good alternative sources for replacing synthetic fibres and reinforcing polymer matrices because of their eco-friendly nature. The present study was undertaken to investigate the fibres extract from Elettaria Cardamomum plant. The extracted Elettaria Cardamomum fibre was treated with NaOH for softening. Natural cellulose fibres extracted from Elettaria Cardamomum stems (ECS) have been characterized for their chemical composition and physical properties.The chemical composition of Elettaria Cardamomumstems (ECS) fi bres is, cellulose 60.44%, lignin 25.25%, wax 0.53%, ash 5.45%. Regarding physical properties of the fibres, single fibre strength was evaluated and the result was compared with cotton fibre and linen fibre.

The Effect of Treatment of Coconut Fiber with Liquid Smoke on Mechanical Properties of Composite

This study aims to determine the effect of liquid smoke treatment on the tensile strength of the single fiber and Coconut fiber (CF) Reinforced Composite. The research method is Immersion the fiber with liquid smoke and heating. First treatment, CF was immersed in liquid smoke for 1, 2, and 3 hours, then dried for 1 hour at a temperature of 40 degrees Celsius. Next, the single fiber tensile test was carried out with the Universal Impact Test Machine and composite impact strength. The results showed that the tensile strength of single fiber TP, P1J, P2J, and P3J of 51.357 MPa, 79.655 MPa, 48.187 MPa, and 58.117 MPa. While the CF composite impact test TP, P1J, P2J, and P3J of 0.514 KJ/m2, 1.385 KJ/m2, 1,085 KJ/m2, and 2,128 KJ/m2. The liquid smoke immersion can increase the tensile strength of single fibers, where 1-hour immersion has the greatest value. In contrast, the impact strength of the CF composites increased at 3 hours, the largest immersion value. The results showed that the fiber soaked in liquid smoke could be an alternative to improve the mechanical properties of CF.

Investigation on mechanical and chemical properties of mechanically extracted banana fibre in pseudostem layers: From Sri Lankan banana (Musa) cultivation waste

This research investigates the factor influencing the quality of the fibre inside the banana pseudostem to determine which layers are suitable for delivering fine banana fibre. This research identifies the banana pseudostem layer-wise properties. Puwalu and Ambun fibres were obtained from the Kurunagala district in Sri Lanka. Banana fibres were separated from pseudostem by using a decorticator machine. Scanning electron microscopy, Fourier transform infrared spectrophotometer (FTIR) and universal tensile tester machine were used for the testing. The test results showed that the middle layers of the pseudostem to be the finest and strong. The lignin contains in the middle layer of fibre was lower than that of the first layer of fibres. The linear density of the ambun middle layer is 25 tex, the average diameter value is 80 µm and range of single fibre strength is 273–270 gf. Linear density of the puwalu middle layer is 29 tex, the diameter value was varying in between 98 and 100 µm and range of single fibre strength is 270–271 gf. The findings of this research will help anybody to select a suitable layer of Sri Lankan banana cultivars fibres based on physical and chemical properties. Then, these fine fibres can be a bridge over the extensive gap between natural cellulose substitute fibre demand.

Characterization of Cellulosic Leaf Fiber from the Typha Angustifolia Plant

ABSTRACT Typha leaves are a rich source of fiber cables and these fibers can also be extracted by chemical retting method and these are easily bio-degradable, and eco-friendly. The main objective of present work is to assess the fiber characteristics such as FTIR, XRD, TGA, SEM, and single fiber tensile properties by varying fiber extraction parameters. In the retting process, IR peaks clearly shows that there was a removal nonfibrous material (NFM). Using X-ray diffraction technique 67.61% crystallinity with a crystallinity index of 0.521 was observed. Fiber tips of SEM images confirm that by increase in chemical concentration and treatment time, there was more removal of NFM and fibrillation found. For the fiber extraction mainly two treatment particulars were varied i.e. sodium hydroxide (10, 20, and 30 gpl) and time (3, 4, 5, and 6 h). Out of various retting conditions, at 20 gpl with 4 and 5 h treatment time shows an excellent tensile strength of single fiber, i.e. 125 Mpa and 179.82 Mpa and 30 gpl with 4 hrs and 5 h observed moderate strength, i.e. 106.03 Mpa and 122.69 Mpa respectively.

Fiber break evolution and fatigue life prediction of CFRP with random fiber distribution

A new method on fatigue life prediction of unidirectional (UD) carbon fiber reinforced plastic (CFRP) is proposed based on fatigue characteristic of single fiber and expansion of broken fiber clusters. Both of statistical fatigue strength of single fiber and non-uniform fiber distribution are considered to assess the fiber break evolution characteristic and the fatigue life of CFRP. A stress redistribution coefficient (SRC) model is proposed to calculate the magnitude of stress overload in intact fibres after nearby fibre break. The SRC depends on not only the distance between broken and intact fibers but also the number of fibers adjacent to the broken fiber. A flowchart is established to predict fatigue life of UD CFRP based on the proposed SRC model. The proposed SRC model predicts clear defection point on the curve of fiber breaking number and stiffness degradation as increase of loading cycles, which agrees well with experimental phenomena in available literatures.

Study on the Performance of Xinjiang Flax Fiber

ABSTRACT In this paper, the physical and chemical properties of Xinjiang Flax fiber were studied systematically, including mechanical properties by single fiber strength meter, average fineness of single fiber, qualitative and quantitative analysis of chemical composition by infrared spectrophotometer, crystallinity and orientation by X-ray diffractometer, and physical morphology by SEM. The results showed that the main chemical composition and content of Xinjiang Flax fiber were: 1.5969% of fatty wax, 6.6814% of water-soluble matter, 3.5058% of pectin, 17.5510% of hemicellulose and 2.1853% of lignin, the average breaking strength was 228.25cN, the average breaking elongation was 1.04 mm and the average breaking time was 2.09 s, and the average fineness of Xinjiang Flax single fiber was 49.43 μm. The fiber surface is rough and adheres to colloid. The internal molecular structure is relatively close, and the fiber macromolecules are arranged orderly in the crystallization zone, with the crystallinity of 69.3% and the orientation of 91.8%. The above data and analysis provide valuable theoretical basis for the degumming and high-quality yarn spinning of Xinjiang Flax, which is conducive to the further development of Xinjiang Flax.

Characterization of lignocellulosic fibres extracted from agricultural biomass: arecanut leaf sheath

In the present study, long staple lignocellulosic fibres were extracted from the arecanut leaf sheath, an agricultural biomass. The arecanut leaf sheath (ANLS) fibres have been extracted by alkali treatment. The important fibre properties such as fibre length, diameter, density, bundle strength, single fibre strength, moisture content and chemical composition are evaluated and compared with commonly available cellulosic fibres. Chemical nature and structure of ANLS fibre are determined using X-ray diffraction and FTIR techniques. The morphological structure and cross-section of the fibres were studied by scanning electron micrographs. The thermal properties of the fibre are characterized by thermo-gravimetric analysis. The potential of ANLS fibre to be used as a textile and reinforcing material is discussed in detail.