Search

The rapid advancement of polymer composites, particularly those reinforced with hybrid kenaf, has positioned them as viable structural materials across diverse industries such as automotive, defense, aerospace, marine, construction, and naval. Despite their growing popularity, recent advances in kenaf yarn‐reinforced thermoplastic acrylonitrile butadiene styrene (ABS) composites for structural applications need more comprehensive coverage in the literature. This article addresses this gap by critically examining the influence of quasi‐isotropic stacking orientation on water absorption, flexural strength, and impact properties in kenaf yarn fiber‐reinforced ABS composites. Prepared using hand layup and compression molding techniques, the composites featured varying stacking orientations, including 0°/0°/0°/0°, 0°/90°/0°/90°, −45°/90°/0°/45°, 90°/−45°/0°/45°, 90°/0°/45°/−45°, and 0°/45°/−45°/90° for kenaf yarn reinforced ABS. The findings reveal that the 0°/45°/−45°/90° configuration offers the best overall mechanical properties and water penetration resistance among quasi‐isotropic stacking sequences, exhibiting low water uptake and higher tensile and flexural strengths of 35.3 and 85.4 MPa, respectively, compared to other sequences. This suggests that incorporating ±45° plies contributes to a balanced distribution of mechanical strength and modulus across different directions, making the 0°/45°/−45°/90° configuration ideal for high‐strength structural applications in kenaf yarn/ABS composites. Highlights: Fiber stacking orientation is the key factor affecting the mechanical performance of kenaf‐based composites.Using the hand layup technique, six stacking orientations (0°/0°/0°/0°, 0°/90°/0°/90°, −45°/90°/0°/45°, 90°/−45°/0°/45°, 90°/0°/45°/−45°, and 0°/45°/−45°/90°) were employed to create kenaf fiber‐reinforced ABS composites.A quasi‐isotropic sequence of 0°/45°/−45°/90° allows the least water penetration due to the strategic placement of ±45° plies in the middle layers of composites.0°/45°/−45°/90° configuration offers the best flexural and tensile properties due to better force distribution within the ±45° plies in the middle layers.Under surface morphological analysis, the optimal fiber stacking sequence contributes to fewer voids and fiber pull‐outs. [ABSTRACT FROM AUTHOR]

The integration of sustainable components in automotive parts is in growing demand. This study involves the entire process, from the extraction of kenaf cellulosic fibers to the fabrication of automotive parts by applying injection molding (sample only) and Resin Transfer Molding (RTM) techniques. Fibers were pretreated, followed by moisture content analysis before composite fabrication. The composite was fabricated by integrating the fibers with polypropylene, maleic anhydride polypropylene (MAPP), unsaturated polyester, and epoxy resin. Mechanical tests were done following ASTM D5083, ASTM D256, and ASTM D5229 standards. The RTM technique was applied for the fabrication of parts with reinforced kenaf long bast fibers. RTM indicated a higher tensile strength of 55 MPa at an optimal fiber content of 40%. Fiber content from 10% to 40% was found to be compatible with or better than the control sample in mechanical tests. Scanning Electron Microscope (SEM) images showed both fiber-epoxy-PE bonding along with normal irregularities in the matrix. The finite element simulations for the theoretical analysis of the mechanical performance characteristics showed higher stiffness and strength in the direction parallel to the fiber orientation. This study justifies the competitiveness of sustainable textile fibers as a reinforcement for plastics to use in composite materials for automotive industries. [ABSTRACT FROM AUTHOR]

Limitation in practical applications of biopolymer–fiber composite is mainly at higher temperatures. Thus, this study highlights the effects of fiber orientation on the durability of polylactic acid (PLA) reinforced with unidirectional (UD) continuous kenaf fibers at elevated temperatures. PLA and long kenaf fiber were fabricated using the hot-pressing method and stacked at fiber orientations of 0°, 45°, or 90°, relative to the tensile force. Dynamic mechanical analysis of the composites shows excellent anti-shock and temperature-resistant properties of the composite. UD PLA–kenaf composites with a 0° fiber orientation showed an ultimate tensile of ∼190 MPa and a flexural strength of ∼235 MPa, and the strength of the composite was able to retain up to 120°C temperature. The debonding behavior of the fiber from the matrix (fiber pull-out) supported by microscopy proved that interfacial failure occurs from the local strains, which initiate cracking. Interfacial failure and stress transfer have caused a remarkable reduction in composite strength when fibers were oriented at 90°. Hence, this current improvement in the performance of the UD PLA–kenaf fiber composite may potentially replace conventional synthetic fibers, especially for structural automotive applications. [ABSTRACT FROM AUTHOR]

Kenaf fiber has recently garnered exponential interest as reinforcement in composite materials across diverse industries owing to its superior mechanical attributes, ease of manufacture, and inherent biodegradability. In the discourse of this review, various methods of manufacturing kenaf/Polylactic acid (PLA) composites have been discussed meticulously, as delineated in recently published scientific literatures. This paper delves into the chemical modification of kenaf fiber, examining its consequential impact on tensile strength and thermal stability of the kenaf/PLA composites. Further, this review illuminates the role of innovative 3D printing techniques and fiber orientation in augmenting the mechanical robustness of the kenaf/PLA composites. Simultaneously, recent insightful explorations into the acoustic properties of the kenaf/PLA composites, underscoring their potential as sustainable alternative to conventional materials have been reviewed. Serving as a comprehensive repository of knowledge, this review paper holds immense value for researchers aiming to utilize the capabilities of kenaf fiber reinforced PLA composites. • Kenaf fiber has gained popularity as a reinforcement in composite materials for its superior mechanical properties and biodegradability. • Recent manufacturing methods of kenaf/PLA composites and their effect on mechanical, thermal and acoustic properties have been investigated. • Chemical modifications enhance the mechanical and thermal properties of the kenaf/PLA composites, broadening the scope of application. • Advancements in 3D printing technologies contribute significantly to the mechanical properties of the kenaf/PLA composites. [ABSTRACT FROM AUTHOR]

Efforts to reduce manufacturing cost and negative environmental impacts have seen the mixture of natural fibre with synthetic fibre in composite structures. However, there are limited studies on the notch effect and fibre orientation on mechanical properties of hybrid fibre metal laminate (FML). In this study, tensile properties of FML with notch and different fibre orientation were investigated. The hybrid FML incorporated with kenaf fibre at the middle layer was compared with FML with three layers of E-glass fibre. Kenaf fibre and E-glass fibre used were in plain woven form. The FML in 2/1 configuration was manufactured through hot press manufacturing method to bond layers of annealed aluminium 5052 to the composite. Tensile test was conducted in a quasi-static manner according to ASTM E8. The results showed FML with three layers of glass fibre exhibited higher tensile strength compared with hybrid FML. However, the introduction of kenaf fibre in hybrid FML reduces the notch and fibre orientation sensitivity compared with glass fibre reinforced FML. [ABSTRACT FROM AUTHOR]

The aim of this work is to study the effect of kenaf volume content and fiber orientation on tensile and flexural properties of kenaf/Kevlar hybrid composites. Hybrid composites were prepared by laminating aramid fabric (Kevlar 29) with kenaf in three orientations (woven, 0o/90o cross ply uni-directional (UD), and non-woven mat) with different kenaf fiber loadings from 15 to 20% and total fiber loading (Kenaf and Kevlar) of 27-49%. The void content varies between 11.5-37.7% to laminate with UD and non-woven mat, respectively. The void content in a woven kenaf structure is 16.2%. Tensile and flexural properties of kenaf/Kevlar hybrid composites were evaluated. Results indicate that UD kenaf fibers reinforced composites display better tensile and flexural properties as compared to woven and non-woven mat reinforced hybrid composites. It is also noticed that increasing volume fraction of kenaf fiber in hybrid composites reduces tensile and flexural properties. Tensile fracture of hybrid composites was morphologically analysed by scanning electron microscopy (SEM). SEM micrographs of Kevlar composite failed in two major modes; fiber fracture by the typical splitting process along with, extensive longitudinal matrix and interfacial shear fracture. UD kenaf structure observed a good interlayer bonding and low matrix cracking/debonding. Damage in composite with woven kenaf shows weak kenaf-matrix bonding. Composite with kenaf mat contains the high void in laminates and poor interfacial bonding. These results motivate us to further study the potential of using kenaf in woven and UD structure in hybrid composites to improve the ballistic application, for example, vehicle spall-liner. POLYM. COMPOS., 36:1469-1476, 2015. © 2014 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

The increase of environmental awareness has led to interest in the use of materials with eco-friendly attributes. In this study, a sandwich composite was developed from polyester and kenaf fiber with various orientation arrangements. Polyester/kenaf sandwich composite was fabricated through the combination of a hand lay-up process and cold compression. The tensile, flexural, and Izod impact tests of the sandwich composites were evaluated by using a universal tensile tester and an impact tester. The thermal stability of polyester/kenaf sandwich composite and plywood were investigated by using a thermogravimetric analyser. Results showed that the polyester/kenaf sandwich composite with kenaf fiber in anisotropy orientation achieved the highest mechanical properties. The kenaf fiber in anisotropic orientation could absorb the impact energy and allow the sandwich composite to withstand greater impact forces compared to composite with fiber in perpendicular or isotropic orientations. The polyester/kenaf sandwich composite also showed higher thermal stability compared to a conventional plywood sheet. Thus, the fabrication of polyester/kenaf sandwich composite with kenaf fiber in an anisotropic orientation design has great potential to replace plywood sheets for beam construction applications. [ABSTRACT FROM AUTHOR]