Properties Of Fibers Research Articles

Influences of sodium hydroxide and oxalic acid treatments on physical, mechanical, thermal properties, and morphology of ramie fibers

The environmentally friendly properties of natural fibers cause their use as reinforcement in polymer matrices to continue to grow. However, its hydrophilic properties can significantly reduce interfacial interactions. Chemical treatment is one method used to reduce the hydrophilic nature of ramie fibers. This study aimed to investigate the effects on ramie fiber of three chemical treatments: oxalic acid at a concentration of 5 (wt.%), sodium hydroxide at 3, 5, and 7 (wt.%), and a combination of both treatments. Physical properties, moisture content, tensile strength, X-ray diffraction, Fourier transform infrared spectroscopy (FT-IR), thermal properties, contact angle, and morphology of ramie fibers before and after treatment were observed in this investigation. FT-IR test results showed a partial loss of amorphous content and more intense cellulose peaks in treated ramie fibers. The combination treatment of alkali and oxalic acid gave the best results, which initiated the dissolution of some of the lignin, hemicellulose, and extractive content. XRD results indicated the surface treatment also led to a 20.35% rise in the crystalline index. In addition, there was a significant increase in tensile strength of 136.10 % in fibers soaked with chemicals. The morphology of the fibers with treatment showed defibrillation and loss of contaminants on the fiber surface, which was the cause of the smaller fiber diameter. Therefore, this optimum treatment is expected to improve the interfacial properties of natural fibers and polymer matrices so that they can enhance the properties of composites when applied in industries.

Experimental study on the triaxial mechanical properties of hybrid steel fiber–reinforced self-compacting concrete

In this study, the triaxial mechanical properties of hybrid steel fiber–reinforced self-compacting concrete (HSFRSCC) were investigated. Based on previous research, a mixture of HSFRSCC that satisfies the requirements of compression and workability performance was determined. Conventional triaxial compression tests were performed at confining pressures of 0, 4, 8, 12, and 16 MPa. The results showed that all the specimens had excellent deformation ability, and both the steel fibers and confining pressure improved the ductility of HSFRSCC. With an increase in the confining pressure, the triaxial peak stress and strain of concrete were increased. The differences in the damage characteristics of HSFRSCC and plain concrete were compared based on scanning electron microscopy test results. Finally, the applicability of the Mohr–Coulomb criterion with that of the Willam–Warnke (W–W) criteria to HSFRSCC was compared. the results showed that the nonlinear W–W criterion had a better fitting effect. Hence, the relationship between triaxial peak stress, peak strain, and confining pressure was established, and the triaxial compression meridian formula for HSFRSCC was obtained.

Effects of heat treatments and cross‐linking on the crystal structure and torsional properties of polyester fibers

AbstractArtificial muscles have attracted great attention as actuators and coiled and twisted monofilament actuators are considered the most promising ones. In the present work, the torsional properties of poly(hexamethylene adipamide) (PA66), poly(ethylene terephthalate) (PET), and high‐strength PET (HTPET) monofilaments were investigated. Furthermore, cross‐linked PET (CPET) monofilaments were melt‐spun by adding 1 wt% of 2‐dimethoxy‐2‐phenylacetophenone (ultraviolet (UV) initiator) and triallyl iso‐cyanurate (cross‐linking agent) in PET chips under UV radiation. The HTPET monofilaments had the highest torsional modulus of 1.1 GPa followed by the PET (0.8 GPa) and PA66 (0.6 GPa) monofilaments. Subsequently, the HTPET monofilaments were subjected to heat treatments under tension. When the heat treatment time was 10 min, the mechanical properties of the HTPET monofilaments also tended to first increase and then decrease with the rise of heat treatment temperature. The molecular arrangement and crystal structure of the HTPET monofilaments were gradually improved with the prolongation of tension heat treatment. The tensile strength and initial modulus of the HTPET monofilaments were 871.4 MPa and 15.8 GPa, respectively. The mechanical properties of the CPET monofilaments first increased and then decreased with the increase of the drawing ratio. When the drawing ratio was 10, the CPET monofilament had a tensile strength of 717.2 MPa, an initial modulus of 16.7 GPa, and a maximum torsional modulus of 1.3 GPa. Therefore, both heat treatment and cross‐linking increased the mechanical strength of the PET monofilaments. CPET and HTPET are possible to be used as artificial muscles.

Study on preparation and property of coir fiber reinforced epoxy resin composite geogrid

Based on the development and application of green composite building materials, this study prepared a coir fiber reinforced epoxy resin composite grid using coir fiber as the reinforcement material. Through tensile tests of a multi rib grid, the effects of coir fiber content, length, and rib spacing on the composite grid were studied. The results showed that with increase in the coir fiber content, the tensile yield force first increased and then decreased, reaching the maximum value at coir fiber content of 1%. When the coir fiber content exceeded 1%, the tensile properties of the composite grid were lower than that of pure epoxy resin. With the increase in the coir fiber length, the tensile yield force of composite grid also first increased and then decreased. At a fiber length of 1 cm, the maximum tensile yield force was obtained, which was 34.33% higher than that of pure epoxy resin grid. Compared with the influence of fiber length and content on the composite grid, the influence of rib spacing on the composite grid was more obvious. At a rib spacing of 1 cm, the tensile yield force reached its maximum.

Oxidation and mechanical properties of SiC fibers after high temperature exposure in air and steam

SiC fibers are widely used in composites exposed to high temperature oxidizing environments. The present study compares the oxidation behavior of SiC fibers and the associated changes in tensile strength upon their exposure to dry air and steam for up to 50 hours at temperatures from 950°C to 1350°C. In both cases, the scale thickness and oxide microstructure were analyzed by scanning electron microscopy. When the SiC fibers were oxidized in air, a crack-free amorphous oxide layer formed at temperatures up to 1200°C, whereas a cracked, crystallized oxide layer was found at 1350°C. By contrast under steam environment, a crystalline oxide forms at 950°C for oxidation times longer than 30 h. In both environments, the fiber strength decreased with increasing exposure time and temperature, the degradation being faster after oxidation in steam compared to dry air. This appears to relate to residual stress in the oxide scale and a reduction in the cross section of the load-bearing unoxidized SiC. An increase in defect size may also contribute to the loss of strength. The oxide scale follows parabolic growth kinetics in both dry air and in steam from 950°C to 1350°C, except at 1350°C for over 30 hours. The oxidation rate in steam is faster than that in dry air, with activation energies of 79.8±1.4 kJ/mol in steam and 153.6±3.4 kJ/mol in dry air, respectively. This work is relevant to the application of SiC fibers and SiC fiber reinforced composites in air and steam environments at high temperature.

Experimental Investigation on Mechanical and Viscoelastic properties of Kenaf, Basalt and Carbon Fiber reinforced Hybrid Epoxy Polymer Composites

Experimental Investigation on Mechanical and Viscoelastic properties of Kenaf, Basalt and Carbon Fiber reinforced Hybrid Epoxy Polymer Composites

Mechanical properties of Kenaf and Palmyra Palm leaf stalk fiber reinforced composite

The kenaf fibers and Palmyra palm leaf stalk fibers (PPLSF) fiber were extracted using retting process then the composite was fabricated by Hand lay-up process using chemically treated unidirectional bilayer fibers mat. The fabricated composites undergone with mechanical properties such as tensile, flexural, impact test, and hardness. Three types of composites were manufactured by varying the weight percentage of fiber content, the composites were: Kenaf-Palmyra Palm Leaf Stalk-Kenaf Fiber Composite (KPKFC), Palmyra Palm Leaf Stalk-Kenaf-Palmyra Palm Leaf Stalk Fiber Composite (PKPFC), and Palmyra Palm Leaf Stalk-Kenaf Fiber Composite (PKFC). The KPKFC and PKPFC had shown significant mechanical properties. The maximum tensile and impact strength was found for PKPFC, the tensile and impact strength was 10.60 MPa and 17.37 J/cm2 respectively. The PKPFC had almost 60.18% and 66.72% more tensile and impact strength than KPKFC respectively. The highest flexural strength was obtained for KPKFC and flexural strength was 19.38 MPa. The KPKFC had 49.12% more flexural strength than PKPFC. The maximum hardness was obtained for KPKFC and the hardness was 25.4 Shore D.

Impact of water combined wet ball milling extraction and functional evaluation of dietary fiber from papaya (Carica papaya L)

This study evaluates the structural, physicochemical, functional and rheological properties of papaya dietary fibers (DFs) extracted by alkaline, water and combination of water/wet ball milling. The particle size of DF subjected to water/wet ball milling (WB-DF) was considerably reduced compared to DF extracted by water (W-DF) or alkaline (AL-DF) methods. WB-DF in comparison AL-DF increased the water holding capacity (WHC) by 4.1 folds, oil holding capacity (OHC) by 1.7 folds and water swelling capacity (WSC) by 2.6 folds. WB-DF also improved the cholesterol adsorption capacity (CAC), glucose adsorption (GAC), nitrite-ion adsorption capacity (NIAC) and antioxidant activity. The FT-IR spectra displayed changes in peak intensities observed in the three modified DFs. In addition, WB-DF showed highest viscosity among all smaples. The distributions of monosaccharides in the DFs were affected by the different extractions. Consequently, DFs extracted through the water/wet ball milling exhibit significant potential for applications in the functional food industry.

Studying the effect of changing optical fibers parameters on their modes properties at 1000 nm wavelength

Optical fiber technology is without a doubt one of the most significant phases of the communications revolution and is crucial to our daily lives. Using the free version (2022) of RP Fiber Calculator, the modal properties for optical fibers with core radii (1.5−7.5) μm, core index (1.44−1.48) and cladding index (1.43−1.47) have been determined at a wavelength of 1000 nm. When the fiber core’s radius is larger than its operating wavelength, multimode fibers can be created. The result is a single-mode fiber in all other cases. All of the calculated properties, it has been shown, increase with increasing core radius. The modes’ intensity profiles were displayed.

Nutritional value and fiber content of cookies prepared from okara flour substitution: study on dietary fiber, isoflavone, and chemical properties

Cookies as a popular and ready-to-eat snack began to be developed as an alternative food for people with special diets. Soy products are known to be a source of inexpensive protein, nutritious and have functional properties. Okara as a soybean residue from soymilk production has nutritional value such as protein, fat, antioxidant like isoflavone and others that can be applied to a variety of food such as cookies. The target of this study is to evaluate the fiber and nutritional value of cookies made from okara flour. Prepared cookies are analyzed for proximate, texture, antioxidant and fiber content. This study used ANOVA and followed with Honest Significants Difference (HSD) consisting 3 treatments (A0B0-without substitution of okara flour, A3B2-20% okara flour substitution and 0,5gram cinnamon powder and A4B2-30% okara flour substitution and 0,5gram cinnamon powder). The range of the cookie’s moisture content, ash, crude protein, fat, and carbohydrate was 2.16-4.01%, 1.39-1.65%, 9.1-17.09%, 17.20-21.07%, and 60.24-65.86% respectively. The highest fiber content (3.52%) and isoflavone level (47.4μg/mg) of cookies were cookies prepared with okara flour substitution 30%.

The Impact of Goode Health LLC Superfood Chocolate Blend Beverage on Peripheral Macro and Microvascular Function

Cardiovascular disease (CVD) is the leading cause of death in the US and world-wide. The are many risk factors associated with elevated risk for and prevalence of CVD; however, it is well documented that reduced macro and microvascular function/health is a major contributing factor. The mechanisms are multifactorial however, reduced vasodilatory reactivity, secondary to elevated oxidative stress and/or inflammation contribute to elevated disease risk. Diets and/or interventions high in antioxidants, polyphenols, and/or anti-inflammatory properties reduce CVD and metabolic disease risk. Furthermore, this is mediated in part through improvements in vascular function. This study tested the hypothesis that 2-weeks of increased daily consumption of a beverage high in antioxidants, polyphenols, and anti-inflammatory properties would improve well-validated indices of peripheral macro and microvascular function in a cohort of Hispanic individuals. METHODS: Six Hispanic individuals (4 males; age: 42±14 yr.; BMI 32±7 kg/m2) participated. All measures were assessed before (pre) and following (post) 14-days of increased daily consumption of the Goode Health LLC Superfood Moroccan Chocolate Blend. During the intervention participants added the chocolate blend powder mix (~28 g) to 8 oz water twice daily. This beverage is high in healthy ingredients including plant-based proteins, prebiotic fiber, antioxidant polyphenols, and anti-inflammatory properties. Peripheral macro and microvascular function/health were assessed pre- and post-intervention as vasodilation in the brachial artery (flow mediated vasodilation; %FMD) and reactive hyperemia (peak mean forearm blood velocity (FBVmean)) in the forearm vasculature respectively following 5-min of forearm ischemia induced by suprasystolic cuff occlusion. RESULTS: Peripheral macrovascular function assessed as %FMD tended to be augmented following Goode Health LLC beverage consumption (Pre: 4.2±2.2 % vs. Post: 5.8±1.6 %, P=0.08). Whereas peripheral microvascular function assessed as peak FBVmean was augmented following the intervention (Pre: 70±17 cm·s−1 vs. Post: 78±20 cm·s−1, P=0.04) CONCLUSION: These preliminary data indicate a positive effect of Goode Health LLC Superfood Moroccan Chocolate Blend consumption on indices of peripheral macro and microvascular function/health. Future studies will continue to expand upon these findings in a larger cohort. Goode Health LLC. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

A comprehensive review on: Mechanical and acoustical characterization of natural fiber-reinforced composite

In our modern era of rapid development, the issue of noise pollution has become increasingly pressing. This relentless surge in noise pollution has brought about significant adverse effects on human health, extending beyond just auditory concerns. To combat this escalating problem, it becomes imperative to explore innovative solutions, such as the utilization of natural fiber-reinforced composites in acoustical applications. These composites offer environmental friendliness, cost-effectiveness, and enhanced mechanical and sound-absorbing qualities. In the context of this review, we examine various methods for evaluating both the mechanical and acoustical attributes of these composites. We examine significant acoustical metrics, including the sound absorption coefficient, sound transmission losses, and noise reflection coefficient, as well as mechanical aspects encompassing tensile, flexural, impact strengths, and hardness. Moreover, this comprehensive review delves into the realm of influencing parameters, which exert a notable impact on the mechanical and acoustical characteristics of natural fiber-reinforced composites. A range of variables is encompassed by these influencing parameters, including fiber properties, binder-filler amount, specimen thickness, etc. It is worth noting that manipulating these parameters can yield significant enhancements in mechanical strength and sound absorption. However, it is crucial to recognize and respect certain limitations to avoid adverse effects. In conclusion, this review emphasizes the importance of carefully considering these performance-influencing parameters to optimize the mechanical and acoustical attributes of natural fiber-reinforced composites. By doing so, we can fully harness the potential of these composites to address the challenges posed by escalating noise pollution effectively.

Effect of Hybridization of Carbon Fibers on Mechanical Properties of Cellulose Fiber–Cement Composites: A Response Surface Methodology Study

Fiber-reinforced cement composites, particularly those incorporating natural fibers like cellulose, have gained attention for their potential towards more sustainable construction. However, natural fibers present inherent deficiencies in mechanical properties and can benefit from hybridization with carbon fibers. This study focuses on the incorporation of cellulose and carbon fibers, in varying contents, into fibrocement composites, employing a Response Surface Methodology (RSM) to optimize the material characteristics. The methodology involves testing, encompassing flexural tensile, compression, and fracture toughness tests. The results indicate an increasing trend in flexural strength for higher carbon fiber content, peaking near 5%. A plateau in flexural strength is observed between 1.2% and 3.6% carbon fiber content, suggesting a range where mechanical properties stabilize. Compressive strength shows a plateau between 1.2 and 3.6% and reaches its highest value (≈33 MPa) at a carbon fiber content greater than 4.8%, and fracture toughness above 320 MPa·m1/2 is achieved with carbon fiber content above 3.6%. This study offers insights into optimizing the synergistic effects of cellulose and carbon fibers in fibrocement composites.

Water Absorption, Thermal, and Mechanical Properties of Bamboo Fiber with Chopped Glass Fiber Filler-Reinforced Polyester Composites

This study explores the investigations of bamboo fiber-reinforced polyester composites with chopped glass fiber (CGF) filler, focusing on addressing the challenges of low mechanical properties, limited thermal stability, and high moisture absorption. The two types of composites were fabricated using the hand layup method, that is, long unidirectional 0° bamboo fiber (BF) and randomly oriented short bamboo fiber (BP) reinforced a polyester matrix with chopped glass fiber (CGF) filler. By incorporating CGF filler, significant improvements in mechanical properties were achieved across both types of bamboo fiber, surpassing the limitations of unfilled composites. Notably, the composite formulation consisting of 40% wt. of unidirectional 0° BF and 5% wt. of CGF filler exhibited superior ultimate tensile strength, flexural strength, impact strength, water absorption, and thermal stability. This composite demonstrated remarkable enhancements, with increases of up to 131.22 MPa, 128.76 MPa, 113.3 kJ/m2, 1.94% water absorption, and up to 255°C (representing a 10% improvement) in thermal stability compared to the unfilled composite. Statistical analysis revealed quadratic models for the mechanical properties of long unidirectional 0° bamboo fiber composites, while water absorption exhibited a linear two-factor interaction model. For randomly oriented short bamboo fiber, the models for tensile, flexural, and water absorption properties were linear, while the impact energy model showed a quadratic relationship. These statistical models provide valuable insights into predicting the properties of bamboo fiber-reinforced polyester composites. This research underscores the significance of bamboo fiber-reinforced polyester composites in wall partition systems. This study paves the way for improved performance in these areas. The findings highlight the potential of incorporating CGF filler, enabling enhanced mechanical strength, increased thermal stability, and improved resistance to moisture-related issues. The derived statistical models offer valuable guidance for predicting the properties of these composites, facilitating their application and adoption in the construction industry.

Dynamic compressive behavior of steel fiber synergistically reinforced cellular concrete under high strain-rate loading

To better understand the reinforcement and toughness effects of steel fibers, a 75-mm split Hopkinson pressure bar (SHPB) device was used to test the uniaxial dynamic compression properties of steel fiber synergistically reinforced cellular concrete (SFSRCC) under high strain rates. The dynamic compression performance characteristics of the SFSRCC, including the stressstrain curve, dynamic strength, impact toughness and failure mode, were analyzed. The results showed that the dynamic strength, peak strain and impact toughness of SFSRCC increase with increasing strain rate. Compared with that of cellular concrete (SAP10S0), a higher steel fiber volume ratio corresponded to a greater enhancement in the dynamic performance characteristic indices of the SFRCC. The maximum increases were 138.4%, 180.0% and 280.0% for the DIF, peak strain, and impact toughness, respectively. The damage degree of the SFSRCC specimen decreased with increasing fiber content, and a larger area of residual "core retention" was observed, which indicated that the impact resistance of the SFSRCC with a high fiber content was improved. An empirical formula that can accurately characterize the dynamic strength increase factor (DIF) of SFSRCC with high strain rates was proposed, and the prediction results obtained by using the DIF of the SFSRCC were highly consistent with the test results, which confirmed its effectiveness. To further quantify the strain rate enhancement effect and fiber content for the reinforcement and toughening ability of SFSRCC, the relationships between the peak strength/peak strain/impact toughness and strain rate and between the DIF increment ratio/strain energy density increment ratio and fiber volume fraction were determined. In conclusion, the dynamic compression performance characteristics of SFSRCC can be enhanced by incorporating an appropriate quantity of steel fibers with a dynamic impact load.

Experimental study on the mechanical property of carbon fiber reinforced polymer with the combined application of digital twin and reduced order algorithm

Experimental study on the mechanical property of carbon fiber reinforced polymer with the combined application of digital twin and reduced order algorithm

Performance of Steel Fiber Reinforced Concrete under Different Cooling Methods at High Temperature

Performance of Steel Fiber Reinforced Concrete under Different Cooling Methods at High Temperature

Drying Shrinkage Properties of Arched Steel Fiber Reinforced Concrete by Volume Fraction of Steel Fiber

Drying Shrinkage Properties of Arched Steel Fiber Reinforced Concrete by Volume Fraction of Steel Fiber

Fourier Transform Infrared (FT-IR) Spectroscopy and Simple Algorithm Analysis for Rapid and Non-Destructive Assessment of Cotton Fiber Maturity and Crystallinity for Plant Mapping.

Information on boll distribution within a cotton plant is critical to evaluate the adaptation and response of cotton plants to environmental and biotic stress in cotton production. Cotton researchers have applied available conventional fiber measurements, such as the high volume instrument (HVI) and advanced fiber information system (AFIS), to map the location and the timing of boll development and distribution within plants and further to determine within-plant variability of cotton fiber properties. Both HVI and AFIS require numerous cotton bolls combined for the measurement. As an alternative approach, attenuated total reflection Fourier transform infrared (ATR FT-IR) spectroscopy was proposed to measure fiber maturity (MIR) and crystallinity (CIIR) of a sample as little as 0.5 mg lint. Extending fiber maturity and crystallinity measurement into a single boll for node-by-node mapping, FT-IR method might be advantageous due to less sampling amount compared with HVI and AFIS methods. Results showed that FT-IR technique enabled the evaluation of fiber MIR and CIIR at a boll level, which resulted in average MIR and CIIR values highly correlated with HVI micronaire (MIC) and AFIS maturity ratio (M). Hence, FT-IR technique possesses a good potential for a rapid and non-destructive node-by-node mapping of cotton boll maturity and crystallinity distribution.

Microstructural Evolution and Failure in Fibrous Network Materials: Failure Mode Transition from the Competition between Bond and Fiber.

For the complex structure of fibrous network materials, it is a challenge to analyze the network strength and deformation mechanism. Here, we identify a failure mode transition within the network material comprising brittle fibers and bonds, which is related to the strength ratio of the bond to the fiber. A failure criterion for this type of fibrous network is proposed to quantitatively characterize this transition between bond damage and fiber damage. Additionally, tensile experiments on carbon and ceramic fibrous network materials were conducted, and the experimental results show that the failure modes of these network materials satisfy the theoretical prediction. The relationship between the failure mode, the relative density of network and strength of the components is established based on finite element analysis of the 3D network model. The failure mode transforms from bond damage to fiber damage as increasing of bond strength. According to the transition of the failure modes in the brittle fibrous network, it is possible to tailor the mechanical properties of fibrous network material by balancing the competition between bond and fiber properties, which is significant for optimizing material design and engineering applications.