Mechanical characterization of untreated waste office paper/woven jute fabric hybrid reinforced epoxy composites

The aim of this work is to assess the opportunity to use untreated waste office paper, alone and in combination with jute fabric, as a reinforcement in epoxy composites. Five different stacking sequences were manufactured and tested. Adding untreated waste office paper sheets has been revealed to increase both flexural and tensile strength of the neat resin and of the untreated jute fabric reinforced composites. The effect of the hybridization on tensile and flexural behavior has been evaluated through scanning electron microscopy observations and acoustic emission. The results confirm that waste office paper sheets can be used as a reinforcement for an epoxy resin, thus representing a viable alternative to paper recycling. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Mechanical and viscoelastic properties of soybean oil thermoset reinforced with jute fabrics and carded lyocell fiber

Composites and hybrid composites were manufactured from renewable materials based on jute fibers, regenerated cellulose fibers (Lyocell), and thermosetting polymer from soybean oil. Three different types of jute fabrics with biaxial weave architecture but different surface weights, and carded Lyocell fiber were used as reinforcements. Hybrid composites were also manufactured by combining the jute reinforcements with the Lyocell. The Lyocell composite was found to have better mechanical properties than other composites. It has tensile strength and modulus of about 144 MPa and 18 GPa, respectively. The jute composites also have relatively good mechanical properties, as their tensile strengths and moduli were found to be between 65 and 84 MPa, and between 14 and 19 GPa, respectively. The Lyocell‐reinforced composite showed the highest flexural strength and modulus, of about 217 MPa and 13 GPa, respectively. In all cases, the hybrid composites in this study showed improved mechanical properties but lower storage modulus. The Lyocell fiber gave the highest impact strength of about 35 kJ/m², which could be a result of its morphology. Dynamic mechanical analysis showed that the Lyocell reinforced composite has the best viscoelastic properties. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Biocomposites developed using water‐plasticized wheat gluten as matrix and jute fibers as reinforcement

Biocomposites developed from wheat gluten using water without any chemicals as plasticizer and jute fibers as reinforcement have much better flexural and tensile properties than similar polypropylene composites reinforced with jute fibers. Wheat gluten is an inexpensive and abundant co‐product derived from renewable resources and is biodegradable but non‐thermoplastic. Previous attempts at developing biocomposites from wheat gluten have used plasticizers such as glycerol or chemical modifications to make gluten thermoplastic. However, plasticizers have a considerably negative effect on the mechanical properties of the composites and chemical modifications make wheat gluten less biodegradable, expensive and/or environmentally unfriendly. In the research reported, we developed composites from wheat gluten using water as a plasticizer without any chemicals. Water plasticizes wheat gluten but evaporates during compression molding and therefore does not affect the mechanical properties of the composites. The effect of composite fabrication conditions on the flexural, tensile and acoustic properties was studied in comparison to polypropylene composites reinforced with jute fibers. Wheat gluten composites had flexural strength (20 MPa), tensile strength (69 MPa) and tensile modulus (7.7 GPa) values approximately twice those of polypropylene composites. Water is an effective plasticizer for wheat gluten and could be used to develop various types of inexpensive and biodegradable wheat gluten‐based thermoplastics. Copyright © 2011 Society of Chemical Industry     

Jute fabric reinforced engineering thermoplastic sandwich composites. I. The effect of molding time

Jute fabric‐reinforced sandwich composites were fabricated using engineering thermoplastics. The jute fabrics were precoated with thermosetting resin to improve their thermal resistance before molding of the composites. Thermal gravimetric analysis (TGA) studies revealed that the resin coated fabrics decomposed at higher temperature than the uncoated jute. The onset of degradation of the coated fibers also falls between that of jute fibers and the thermoset resins. This indicates the presence of good interfacial bonding between jute fibers and both resins. Isothermal TGA studies revealed that jute could withstand brief exposure to higher temperature at 270 and 290°C. The sandwich composites were fabricated at 270°C by compression molding for 1.5 and 3 min in each case, and then characterized by flexural, tensile and morphological studies, i.e., SEM and optical microscopy. The uncoated jute fabric yielded composites of superior mechanical properties even with 3 mins molding at 270°C which is close to the degradation temperature of uncoated jute fibers. This is an indication that it is feasible to prepare jute fiber filled engineering polymer composites provided the exposure time at high temperature during processing does not exceed 3 mins as determined by TGA isothermal studies. SEM studies revealed strong fiber/matrix interfacial bonding between jute and the thermoset resins while the inferior mechanical properties of the resin coated sandwich composites could be attributed to the poor interfacial bonding between the already cured thermoset coating and the matrix based on optical microscopy of the polished cross‐sections. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Tensile,flexural and impact properties of jute fibre-based thermosetting composites

Abstract

The present study reports static and impact mechanical properties of jute fibre-based thermosetting composites using woven and flat braided jute fabrics. Tensile, three-point flexural and low-to-medium energy drop-weight impact tests were conducted and mechanical properties were evaluated to study their dependence upon surface modifications of the fibre materials due to bleaching and coating treatments. Full-bleaching (longer and rigorous) treatments improved interfacial bonding and tensile strength properties of the woven jute composites compared to unbleached and half-bleached counterparts. Bleaching treatments did not seem to improve the flexural strength of composites. Unbleached (natural) jute composites have relatively better flexural strength due to reduced microstructural waviness or fibre crimping to facilitate flexural failure. With coated jute yarns, the tensile properties of the resultant flat braided composites slightly degraded, whereas the flexural properties showed clear improvements. The changes in the mechanical properties were broadly related to the accompanying modifications and to the state of microstructural imperfections, namely fibre/matrix interfacial adhesion, severity of resin matrix shrinkage during the curing process, fibre/matrix debonding and distribution of disbonds within the matrix region, and also to the relative fibre filament density along the loading axis, in the cured composite structure. There was a clear indication that natural woven jute composites could be more effective in applications requiring better impact damage resistance, energy absorption capability and improved progressive crushing behaviour.     

Coating of jute with natural rubber

Jute fabric was coated with natural rubber to develop double‐texture rubberized waterproof fabric and fabric‐reinforced rubber sheeting for hospitals. The vulcanization of such natural‐rubber‐coated flexible composites at 120°C for 3 h produced optimum effects. The jute/natural‐rubber composite was much superior to a conventional polyester/natural‐rubber composite for producing such double‐texture rubberized fabric with respect to the fabric‐to‐natural‐rubber adhesion, breaking strength, tear strength, abrasion resistance, puncture resistance, and biodegradability. For fabric‐reinforced rubberized sheeting, the jute/natural‐rubber composite was superior to a conventionally used cotton/natural‐rubber composite with respect to the fabric‐to‐natural‐rubber adhesion, breaking strength, tear strength, and abrasion resistance. However, for both applications, the jute‐based products were commonly found to be less extensible, heavier, and thicker. Unsaturation in the lignin fraction of jute established a chemical linkage with the unsaturation of natural rubber via sulfur at the jute/natural‐rubber interface. An examination of the surface morphology of uncoated and coated jute fabrics by scanning electron microscopy revealed a good degree of deposition and filling even in the intercellular regions of jute by a cohesive mass of natural rubber, which remained unseparated from the fiber, when mechanical force was applied. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 484–489, 2005     

黄麻纤维增强不饱和聚酯树脂初步研究

以油酸为偶联剂,将氢氧化钠-油酸处理后的黄麻纤维布作为填充材料制备了不饱和聚酯复合材料,并对氢氧化钠处理黄麻纤维的适宜浓度、复合材料的拉伸强度、冲击强度、吸水率进行了研究测试。结果表明:氢氧化钠的适宜浓度为20%,黄麻纤维增强不饱和聚酯树脂的冲击强度及拉伸强度最大值分别为12.75 kJ/m2和33.05 MPa,复合材料的最大吸水率为4.07%。经油酸处理的黄麻纤维可有效提高不饱和聚酯复合材料的性能。     

Role of gamma radiation and EGDMA on the physico–mechanical properties of jute fabrics/polypropylene composites

Jute fabrics reinforced polypropylene (PP) composites (45 wt % fiber) were prepared by compression molding and their mechanical properties were investigated. Both jute fabrics and PP sheets were treated with gamma radiation (250–1,000 krad dose) at a rate of 350 krad/h. Irradiated jute fabrics were soaked into ethylene glycol dimethacrylate (EGDMA) solutions (5–40% by weight) and cured in an oven at different temperatures (40–100°C) for 60 min. The percentage of polymer loading (PL) was evaluated and found that 20% EGDMA‐treated jute fabrics contains the highest PL. Composites made of 20% EGDMA‐treated jute fabrics were studied further. It was found that the treatment using the EGDMA improved the mechanical properties of the composites significantly. Scanning electron microscopy and aging properties of untreated and treated composites were performed. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers     

Mechanical properties of surface modified jute fiber/polypropylene nonwoven composites

In this study, the jute/polypropylene nonwoven reinforced composites were prepared using film stacking method. The surface of jute fibers was modified using alkali treatment. These alkali treated jute fiber nonwoven composites were analyzed for their tensile and flexural properties. Increasing the amount of jute fibers in the nonwovens has improved the mechanical properties of their composites. The effect of stacking sequence of preferentially and nonpreferentially aligned nonwovens within the composites was also investigated. The flexural and tensile moduli of composites were found to be significantly enhanced when nonwovens consisting of preferentially and nonpreferentially aligned jute fibers were stacked in an alternate manner. The existing theoretical models of tensile modulus of fiber reinforced composites have been analyzed for predicting the tensile modulus of nonwoven composites. In general, a good agreement was obtained between the experimental and theoretical results of tensile modulus of nonwoven composites. POLYM. COMPOS., 35:1044–1050, 2014. © 2013 Society of Plastics Engineers     

The effect of atmospheric plasma treatment of recycled carbon fiber at different plasma powers on recycled carbon fiber and its polypropylene composites

To increase the mechanical properties of recycled carbon fiber-reinforced polypropylene (PP) composites, recycled carbon fibers (RCF) were subjected to atmospheric plasma treatment at different plasma powers (100, 200, and 300 W). The changes on surface topography and roughness of RCF were examined by atomic force microscopy. Plasma treatment of RCF increased the roughness value of RCF. The variation of surface elemental compositions and tensile strength of RCF were determined by using X-ray photoelectron spectroscopy and tensile test, respectively. Plasma-treated RCF-reinforced PP composites were fabricated using high speed thermo-kinetic mixer. Plasma treatment of RCF at 100 W increased the tensile and flexural strength values of RCF-reinforced PP composites considerably by 17 and 11%, respectively. However, plasma treatment of RCF at higher plasma powers (200 W and 300 W) decreased tensile and flexural strength values of composites because of the etching of RCF. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47131.     

Recycling of jute textile in phenol formaldehyde–jute composites

Jute textile was recycled into composites using different percents of phenol formaldehyde (PF) resin. The effect of the resin percent, from 12 to 30%, on the flexural strength, tensile strength, water absorption, and thickness swelling of the produced composites was studied. To improve the dimensional stability of the produced composites, jute textile was acetylated or steamed. The effect of steaming and acetylation on the structure and thermal stability of jute fibers was studied using Fourier Transform Infrared (FTIR) spectroscopy and Thermogravimetric analysis (TGA), respectively. The effect of these treatments on the flexural strength, tensile strength, water absorption, and thickness swelling of the produced composites was studied. Steaming of jute textile was superior to acetylation in improving the dimensional stability. Cyclic wetting and drying test of the composites showed that steaming of the jute textile resulted in much less irreversible and reversible thickness swelling than in case of using acetylated or untreated jute textile. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3588–3593, 2003     

Effect of Ultraviolet Radiation on the Mechanical and Dielectric Properties of Hessian Cloth/PP Composites with Starch

Hessian cloth (jute fabrics) reinforced poly(propylene) (PP) composites (45 wt% fiber) were prepared by compression molding and the mechanical properties were evaluated. Jute fabrics and PP sheets were treated with UV radiation at different intensities and then composites were fabricated. It was found that mechanical properties of the irradiated jute and irradiated PP-based composites were found to increase significantly compared to that of the untreated counterparts. Irradiated jute fabrics were also treated with aqueous starch solution (1–5%, w/w) for 2–10 min. Composites made of 3% starch-treated jute fabrics (5 min soaking time) and irradiated PP showed the best mechanical properties. Tensile strength, bending strength, tensile modulus, bending modulus and impact strength of the composites were found to improve 31, 41, 42, 46 and 84% higher over untreated composites. Water uptake, thermal degradation and dielectric properties of the resulting composites were also performed.     

Effect of stacking sequence on mechanical properties of hybrid flax/jute fibers reinforced thermoplastic composites

In this study, the hybrid composites were prepared by stacking jute/PP nonwoven and flax/MAPP woven fabrics in defined sequences. Polypropylene (PP) and maleic anhydride grafted polypropylene (MAPP) were used as matrix materials. Jute and flax fibers were treated with alkali solution in order to improve the interface properties of the resultant composites. The mechanical properties of these hybrid composites were analyzed by means of tensile, flexural, and drop‐weight impact tests. The effect of fabric stacking sequence on the mechanical properties of the composites was investigated. The stacking of nonwovens at the top and in alternate layers has resulted in maximum flexural strength, flexural stiffness, and impact force. It was also shown that hybrid composites have improved tensile, flexural, and impact properties in comparison to neat PP matrix. POLYM. COMPOS., 36:2167–2173, 2015. © 2014 Society of Plastics Engineers     

Mechanical,thermal and degradation properties of jute fabric – reinforced polypropylene composites: Effect of potassium permanganate as oxidizing agent

Mechanical properties of jute fabrics‐reinforced polypropylene composites were measured with reference to fiber loading and found highest at 45% by the weight of jute fabrics. Jute fabrics were treated with potassium permanganate in acid (oxalic acid and sulphuric acid) and alkaline (KOH) media in order to investigate the oxidizing effect on the properties of the composites. Solutions of oxalic acid, sulphuric acid, and KOH were prepared in water as 1.0–10.0% w/v, 0.1–2.0% v/v, and 1.0–10.0% w/v, respectively, where percentage of KMnO4 was maintained at 0.01% w/v. Among the treatments, 5.0% oxalic acid treated jute composite showed better mechanical performance. Thermogravimetric (TG/DTG) data of PP, jute fabrics and composites showed that thermal degradation temperatures of composites shifted to higher temperature regions compared to PP or jute fabrics. The treatment of jute fabrics improves thermal stability of the composites. Treated jute composites were found less degradable in soil, water and simulated weathering conditions and also found less water sensible compared to control composite (45% w/w jute fabrics). POLYM. COMPOS., 2013. © 2013 Society of Plastics Engineers     

Study of jute fiber reinforced polyester composites by dynamic mechanical analysis

Cyanoethylation of jute fibers in the form of nonwoven fabric was studied, and these chemically modified fibers were used to make jute–polyester composites. The dynamic mechanical thermal properties of unsaturated polyester resin (cured) and composites of unmodified and chemically modified jute–polyester were studied by using a dynamic mechanical analyzer over a wide temperature range. The data suggest that the storage modulus and thermal transition temperature of the composites increased enormously due to cyanoethylation of fiber. An increase of the storage modulus of composites, prepared from chemically modified fiber, indicates its higher stiffness as compared to a composite prepared from unmodified fiber. It is also observed that incorporation of jute fiber (both unmodified and modified) with the unsaturated resin reduced the tan δ peak height remarkably. Composites prepared from cyanoethylated jute show better creep resistance at comparatively lower temperatures. On the contrary, a reversed phenomenon is observed at higher temperatures (120°C and above). Scanning electron micrographs of tensile fracture surfaces of unmodified and modified jute–polyester composites clearly demonstrate better fiber–matrix bonding in the case of the latter. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 71: 1505–1513, 1999     

Physical and mechanical characterization of jute fabric composites

As‐received and washed jute fabrics were used as reinforcement for a thermoset resin. The mild treatments performed on the jute fabrics did not significantly affect their physical and thermal behaviors. The washed fibers absorbed less water than the unmodified (as received) ones, indicating that the coating used to form the fabrics was hygroscopic. Measurements of the fiber mechanical properties showed a high dispersion due to fiber irregularities, although the values obtained were in agreement with data reported in the literature. These results were also analyzed with the Weibull method. To investigate the effect of the jute treatments on the interface properties, impact, compression, and tensile tests were carried out. The composites made from as‐received jute had the highest impact energy, which was probably associated with weak interfacial adhesion. Composite samples behaved more ductilely in compression than in tensile situations due to the brittle characteristics of the resin used as matrix. The effect of the orientation of the fibers with respect to the direction of the applied force in the different mechanical tests was also studied. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 639–650, 2005     

挤出-注塑制备黄麻增强PLA复合材料及其性能

通过挤出共混、造粒、注射成型的方式制备了黄麻纤维填充聚乳酸(PLA)复合材料,研究了复合材料的力学性能以及黄麻与PLA之间的微观界面形貌。结果表明:黄麻的加入,并没有很好地改善黄麻/PLA复合材料的拉伸强度和弯曲强度;碱处理后的黄麻与PLA之间的界面性能有所改善;碱处理黄麻的加入,改善了黄麻/PLA复合材料的断裂伸长率与冲击韧性。     

Composites based on jute fibers and phenolic matrices: Properties of fibers and composites

Composites based on phenolic matrices and both untreated and alkali and ionized air–treated jute fibers were prepared. Different fiber lengths and fiber content were used to reinforce the phenolic matrices. The jute fibers were characterized with respect to lignin, holocellulose, ash, and humidity contents and also to the crystallinity index. The mechanical properties of fibers were investigated by means of tensile analysis and the morphology by SEM. The untreated and treated jute fiber–reinforced composites were characterized as to water absorption. The mechanical property and morphological aspects of the composites were evaluated by impact strength and photomicrographs obtained from SEM. Among the jute fiber treatments considered in the present work, the treatment with a solution of 5% NaOH presented the best results because: (1) the fiber presented a higher tensile strength, and a larger percentage of elongation at break; (2) the composite reinforced with this fiber presented the highest impact strength results when this was the unique treatment (20% of fiber), as well as when it was combined with ionized air (30% of fiber); and (3) the composite that presented the lowest water uptake was that reinforced with this fiber. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1077–1085, 2004     

A comparative analysis of woven jute/glass hybrid polymer composite with and without reinforcing of fly ash particles

The objective of this research article is to compare the mechanical and tribological properties of jute‐glass‐fiber‐reinforced epoxy (J‐G‐E) hybrid composites with and without fly ash particulate filler. A dry hand lay‐up technique is used to fabricate all the laminates. The properties including flexural strength, tensile strength, flexural modulus, and erosion behavior of all the composites are evaluated as per American Society for Testing and Materials (ASTM) standards. The fly ash particulate‐filled hybrid composite shows a better mechanical and tribological property. The maximum flexural strength and flexural modulus are obtained for GJGJ+ 5 wt% fly ash filler epoxy composites. Whereas the maximum tensile strength is obtained for GJJG+ 10 wt% fly ash filler epoxy composites. Scanning Electron Microscopy (SEM) analysis also has been carried out to categorize mechanical and tribological behavior of composites. POLYM. COMPOS. 37:658–665, 2016. © 2014 Society of Plastics Engineers     

Mechanical properties of phenolic composites reinforced with jute/cotton hybrid fabrics

Mechanical properties (tensile, flexural, impact, and dynamic mechanical thermal analysis) of novolac type phenolic composites reinforced with jute/cotton hybrid woven fabrics were investigated as a function of fiber orientation and roving/fabric characteristics. Scanning electron microscopy (SEM) was carried out to investigate the fiber‐matrix adhesion. Results showed that the composite properties are strongly influenced by test direction and rovings/fabric characteristics. The anisotropy degree was shown to increase with test angle and to strongly depend on the type/architecture of fabric used, i.e., jute rovings diameter, relative fiber content, etc. It was possible to obtain composites with higher mechanical properties and lower anisotropy degree by producing cross‐ply laminates. Best overall mechanical properties were obtained for the composites tested along the jute rovings direction. Composites tested at 45° and 90° with respect to the jute roving direction exhibited a controlled brittle failure combined with a successive fiber pullout, while those tested in the longitudinal direction (0°) exhibited a catastrophic failure mode. Our results indicate that jute promotes a higher reinforcing effect and cotton avoids catastrophic failure. Therefore, this combination of natural fibers is suitable to product composites for lightweight structural applications. POLYM. COMPOS., 26:1–11, 2005. © 2004 Society of Plastics Engineers.