Effect of gamma radiation on mechanical properties of pineapple leaf fiber (PALF)-reinforced low-density polyethylene (LDPE) composites

The objective of this work is to investigate the influence of the utilization of dammar gum (DG), which is a biodegradable and renewable binder, on the mechanical properties of short pineapple leaf fiber (PALF) reinforced tapioca biopolymer (TBP). Samples with variable DG concentrations (10%, 20%, 30%, and 40% by weight) and a constant 30% PALF composition were created with varying TBP percentages using an internal mixing process and compression molding. The results showed that PALF‐TBP with 10% DG had the highest mechanical properties with tensile, flexural, and impact strength of 19.49 MPa, 18.53 MPa and 13.79 KJ/m2, respectively. Scanning electron microscopy (SEM) images prove the enhanced mechanical characteristics. In addition, Fourier transform infrared spectroscopy (FTIR) analysis showed that the DG improves the matrix and PALF interface. The results show that the utilization of DG significantly enhanced the mechanical characteristics of composites. In addition, it is anticipated that it will be able to create PALF‐TBP‐DG composites as a potential alternative for conventional polymers in various applications, especially in engineering applications such as automotive and packaging industries. Therefore, it is expected to be capable of contributing to sustainable development goals (SDGs).Highlights Recent studies show that damar gum (DG) has potential as a sustainable binder. Optimal composition is a critical factor in bio‐composite manufacturing. The mechanical properties improved the most when 10 wt% of DG was applied. DG could serve as a viable substitute for petroleum‐derived coupling agents. Bio‐composites may serve as alternative polymers for forthcoming applications.

The mechanical properties of pineapple leaf fibre (PALF)/carbon hybrid laminate composites at anti-symmetric ply orientation

This paper analyzes several existing pineapple leaf fiber degumming methods and their advantages and disadvantages and describes its relationship with the degumming from the structure characteristics and chemical properties of pineapple leaf fiber. The author puts forward the pineapple leaf fiber degumming technology should be to "high-quality, efficient, low consumption, low pollution" direction of development, and put forward a new method of degumming. By means of scanning electron microscope, infrared spectroscopy, mechanical properties, thermal gravimetric analysis, differential scanning calorimetry and other means, to study the structure, mechanical properties and thermal properties of pineapple leaf fiber biochemical degumming treatment. The results show that: biochemical degumming can take off the original fiber, fiber surface glue residue, single fiber are glial exist, but the fiber separation in good condition, the fiber surface is smooth; hemicellulose degradation in biochemical degumming process, but did not completely removed; no effect on biochemical degumming of pineapple leaf fiber structure has good effect, degumming the treated fiber; degumming relative strength; fiber still has relatively high heat resistance.

Due to their biodegradability, affordability, low density, and numerous other benefits, natural fiber polymer composites are preferable to conventional GFRP in maritime applications. However, when exposed to moisture, their mechanical qualities deteriorate. A significant agricultural waste called pineapple leaf fiber (PALF) can be employed as reinforcement in epoxy matrices. Improved interfacial bonding between phases improves interfacial bonding and hence enhance mechanical and water absorption properties. Only evaluation of mechanical properties is undertaken in this paper. Nanoclay in 1.5 and 3 wt% was incorporated in epoxy resin via magnetic stirring and ultrasonication. PALF fibers were subjected to NaOH treatment and was analyzed using SEM and FTIR techniques. Hand layup and compression moulding were used to fabricate composites using a nanoclay-epoxy resin combination and chemically treated PALF (20 & 30 wt%). The combination of 30 wt% PALF and 1.5 wt% nanoclay results in the maximum mechanical properties, namely tensile and flexural properties. The results of SEM investigation of fractured specimens show that interfacial bonding in epoxy composites containing PALF is poor while that in epoxy composites containing PALF and 1.5 wt% nanoclay is excellent. Due to nanoclay agglomerations, bonding is inadequate at 3 wt% nanoclay, which lowers the mechanical properties.

In this paper, the effects of stacking sequence and ply orientation on the mechanical properties of pineapple leaf fibre (PALF)/carbon hybrid laminate composites were investigated. The hybrid laminates were fabricated using a vacuum infusion technique in which the stacking sequences and ply orientations were varied, which were divided into the categories of cross-ply symmetric, angle-ply symmetric, and symmetric quasi-isotropic. The results of tensile and flexural tests showed that the laminate with interior carbon plies and ply orientation [0°, 90°] exhibited the highest tensile strength (187.67 MPa) and modulus (5.23 GPa). However, the highest flexural strength (289.46 MPa) and modulus (4.82 GPa) were recorded for the laminate with exterior carbon plies and the same ply orientation. The fracture behaviour of the laminates was determined by using scanning electron microscopy, and the results showed that failure usually initiated at the weakest PALF layer. The failure modes included fibre pull-out, fibre breaking, matrix crack, debonding, and delamination.

In this work, the mechanical and thermal properties of pineapple leaf fiber (PALF)/poly (lactic acid) (PLA) composites were studied. Pineapple leaf fibers were pretreated with 4 %wt sodium hydroxide solution followed by various silane solutions i.e. γ-(aminopropyl) trimethoxy silane (APS), γ-methacrylate propyl trimethoxy (A174) and bis [3-(triethoxysilyl) propyl] tetrasulfide (Si69). FTIR results show a significant functional groups of C=O and C=C of methacrylic group, NH2group and Si-O which are the characteristic of these silane coupling agents. SEM micrographs of pretreated PALF showed a rough surface while untreated and silane treated PALF revealed less roughness. It was found that the tensile strength at break of PLA is 56 MPa and tensile strength of composites decreased when fiber content increased. The tensile modulus of silane treated PALF composites were higher than PLA, whereas their impact strength were similar to PLA. Si69 treated PALF showed lower impact strength compared to the others silanes treated fiber which indicates more phase separation between fiber and matrix. This is related to high percentage of crystallinity of composite from Si69 treated fiber. It was also found that the addition of PALF did not change the glass transition temperature and melting temperature of PLA while the percentage of crystallinity increases as the fiber content increased. In addition WAXS study of composite from Si69 treated fiber reveals sharp crystalline peaks of PLA while the others silane treatments show amorphous characteristic of PLA.

Pineapple fiber which is rich in cellulose, relatively inexpensive, and abundantly available has the potential for polymer reinforcement. This research presents a study of the tensile properties of pineapple leaf fiber and pineapple peduncle fiber reinforced polyester composites. Composites were fabricated using leaf fiber and peduncle fiber with varying fiber length and fiber loading. Both fibers were mixed with polyester composites the various fiber volume fractions of 4, 8 and 12% and with three different fiber lengths of 10, 20 and 30 mm. The composites panels were fabricated using hand lay-out technique. The tensile test was carried out in accordance to ASTM D638. The result showed that pineapple peduncle fiber with 4% fiber volume fraction and fiber length of 30 mm give highest tensile properties. From the overall results, pineapple peduncle fiber shown the higher tensile properties compared to pineapple leaf fiber. It is found that by increasing the fiber volume fraction the tensile properties has significantly decreased but by increasing the fiber length, the tensile properties will be increased proportionally. Minitab software is used to perform the two-way ANOVA analysis to measure the significant. From the analysis done, there is a significant effect of fiber volume fraction and fiber length on the tensile properties.

This study deals with the analysis of dynamic mechanical, thermal and flammability properties of treated and untreated pineapple leaf fiber (PALF) and kenaf fiber (KF) phenolic composites. Results indicated that storage modulus was decreased for all composites with increases in temperature and pattern of slopes for all composites, having almost the same values of E' at glass transition temperature (Tg). The peak of the loss modulus of pure phenolic composites was shown to be much less. After the addition of kenaf/PALF, peaks were higher and shifted towards a high temperature. The Tan delta peak height was low for pure phenolic composites and maximum for 60% PALF phenolic composites. Cole-Cole analysis was carried out to understand the phase behavior of the composite samples. Thermogravimetric analysis (TGA) results indicated that pure phenolic composites have better thermal stability than PALF and kenaf phenolic composites. Vertical and horizontal UL-94 tests were conducted and showed pure phenolic resin is highly fire resistant. The overall results showed that treated KF composites enhanced the dynamic mechanical and thermal properties among all PALF/KF composites.

In this article, gray relational analysis (GRA) was carried out to study the influence of fiber length, fiber loading, and injection parameters on the mechanical, thermal, and morphological properties of the developed green composites. The green composite was developed by chemically modifying the pineapple leaf fiber (PLF). PLF was chemically treated with 1% Na2CO3 for a period of 6 h. The chemically modified PLF was chopped at a fiber length (L) of 2, 3, 4, 5, and 6 mm. The fiber loading (D) was also varied to 10, 20, and 30 wt% to study the effect of both fiber length and loading on the tensile and flexural properties of the PLF/PLA green composite developed through injection molding. GRA was employed to determine the optimal fiber length and fiber loading for achieving better tensile and flexural properties of PLF/PLA green composite. The injection parameters considered for producing the PLF/PLA green composite were (a) injection pressure (70, 90, and 110 bars), (b) injection speed (40, 50, and 60 mm/s), and (c) melting temperature (165, 175, and 185°C). The mechanical (tensile, flexural, compression, and shear) and thermal (TGA: thermogravimetric analysis and DTG: derivative thermogravimetric analysis) behavior of the developed PLF/PLA green composite was studied and analyzed. The morphology of the fractured specimens was also inspected using field‐emission scanning electron microscope (FESEM).

Short pineapple‐leaf‐fiber‐(PALF)‐reinforced low‐density polyethylene (LDPE) composites were prepared by melt‐mixing and solution‐mixing methods. In the melt‐mixing technique, a mixing time of 6 min, rotor speed of 60 rpm, and mixing temperature of 130°C were found to be the optimum conditions. Tensile properties of melt‐mixed and solution‐mixed composites were compared. Solution‐mixed composites showed better properties than melt‐mixed composites. The influence of fiber length, fiber loading, and orientation on the mechanical properties has also been evaluated. Fiber breakage and damage during processing were analyzed from fiber distribution curve and optical and scanning electron micrographs. Considering the overall mechanical properties and processability characteristics, fiber lenght of 6 mm was found to be the optimum length of pineapple leaf fiber for the reinforcement in LDPE. The mechanical properties were found to be enhanced and elongation at break reduced with increasing fiber loading. Longitudinally oriented composites showed better properties than randomly and transversely oriented composites. Recyclability of the composite was found to be very good. A comparison of the properties of the PALF‐reinforced LDPE composites with those of other cellulose‐fiber‐reinforced LDPE systems indicated superior performance of the PALF–LDPE composites.© 1995 John Wiley & Sons. Inc.

In tropical regions such as the Philippines, pineapple leaf fiber (PALF) is abundantly available as a low-cost and renewable source for industrial purposes. In this research, PALF was used as a reinforcing material for cement-based composites to open up further possibilities in waste management. Since natural fibers are not fully compatible with the matrix due to their hydrophilic nature, surface treatment is necessary to enhance the fiber-matrix bonding. Fibers were treated using sodium hydroxide (NaOH) with varying concentrations (4%, 8% and 12%) for 6-hr immersion time at room temperature. PALF was then added at varying content (1%, 4% and 7% w/w cement) to the concrete mixture with a design mix ratio of 2:1 (sand: cement) and a constant water-cement ratio of 0.55. The samples were mechanically characterized after 28 curing days following ASTM C209 and ASTM C473. Full factorial experimental design (FFED) was used to investigate the effects of alkali treatment and the fiber content on the mechanical strengths of the composite. Experimental methods, analysis of variance (ANOVA) and normality test were carried out to evaluate, analyze and validate the results. The best results for tensile strength parallel to the surface and flexural strength at 2.028 MPa and 1.495 kN, respectively, were observed at composites with 1% PALF with 4% NaOH. Meanwhile, composites with 1% PALF with 12% NaOH showed the best result for tensile strength perpendicular to the surface at 1.681 MPa. According to ANOVA results, only the model for the tensile strength perpendicular to the surface showed a curvilinear behavior (p-value=0.012). Results revealed that the factor with the most significant effect was the interaction of the fiber content and alkali treatment on the tensile strength parallel to the surface (p-value=0.000), tensile strength perpendicular to the surface (p-value=0.001) and flexural strength (p-value=0.001).

In recent years natural fibres such as sisal, jute, kenaf, pineapple leaf and banana fibres appear to be the outstanding materials which come as the viable and abundant substitute for the expensive and non-renewable synthethic fibre. This paper investigate the effect of fibre length and fibre content on the tensile properties of pineapple leaf fibre (PALF) reinforced unsaturated polyester (UP) composites. PALF as reinforcement agent will be employed with UP to form composite material specimens. The various of fiber length (<0.5, 0.5–1, and 1-2 mm) and fibre content (0, 5, 10 and 15 % by volume) in UP composite have been studied. The fabrication of PALF/UP composites used hand lay-up process, and the specimens for tensile test prepared follow the ASTM D3039. The result obtained from this study show that the 1-2 mm fibre length has higher tensile strength (42 MPa) and tensile modulus (1344 MPa) values compared to fibre length of <0.5 mm (30 MPa and 981 MPa) and 0.5-1 mm (35.40 MPa and 1020 MPa) respectively. Meanwhile, for the effect of various fibre content in study has shown that the increase of fibre content has decreased in tensile strength dan tensile modulus of composites. The increase of fibre content due to poor interfacial bonding and poor wetting of the fibre by unsaturated polyster. The treatment of natural fibre are suggested in order to improve the interfacial adhesion between natural fibre and the unsaturated polyester.

Synthetic fiber composites are used in diversified applications because of their high strength-to-weight ratio. The energy associated with the production of synthetic fibers and their non-degradable characteristics is a major factor of concern looking from an environmental point of view. Natural fibers are derived from plants and animals, are biodegradable, and have properties similar to synthetic fibers. Pineapple leaf fibers (PALF) are obtained from pineapple leaves and can be effectively used as a reinforcement in the polymer matrix. PALF-based composite can be used in automobile, aerospace, sports, biomedical and furniture industries. Utilizing pineapple leaves for producing fibers which will be used in composites will not only reduce the associated environmental problems but also will give lucrative income opportunities to farmers and industries. This review paper deals with surface treatment methods for PALF. Mechanical and thermal properties of PALF reinforced composite are discussed in detail. The hybrid composite formed by PALF as one element is discussed. Overall, this review article highlights the previous work and identifies the gap for future research in the field of PALF reinforced composites.

Pineapple Leaf Fiber (PALF), usually recognized as a sustainable material, is derived from agricultural waste with versatilities and great values for textile and composite applications. This review provides a comprehensive summary and update on PALF, tracing its journey from plantation to final product by offering an explicit introduction of its production, properties, processing, and applications. It begins with an outline on the PALF’s cultivation, distribution, and production. Then, the complex processing of PALF is well demonstrated by investigating the technological advancements across three decades in extraction methods and degumming techniques, including biological, and synergistic approaches. Subsequently, the structure and properties of PALF are discussed in terms of anatomical structure, chemical composition, mechanical strength, thermal behavior, and antimicrobial properties. In addition, the effects of different chemical modifications on PALF’s properties are summarized, highlighting the fiber’s remarkable versatility. This study further maps PALF’s diverse applications along with the corresponding processing techniques. These applications span from textile manufacturing, composite materials to innovative waste utilization strategies. From knitted fabrics, aerogels to creative waste management solutions like fuel briquettes, it underscores the fiber’s transformative potential. Supported by a rigorous Life Cycle Assessment (LCA), this review evaluates PALF’s environmental impact, positioning it as a revolutionary sustainable material that aligns with circular economic principles.

Pineapple leaf fiber (PALF) is known as pineapple residue and has potential as a textile material. Typical yarn manufacturing adopts ring spinning technique, yet it is challenging for course fibers, including PALF. PALF has been used in clothing and paper production using textile thread. It has the highest modulus among leaf fibers, comparable to synthetic fibers such as aramid and glass, and possesses the greatest tensile strength among leaf fibers. PALF has high fineness index makes it ideal for industrial yarn and woven fabric applications. Using natural fibers offers benefits such as being environmentally friendly, cost-effective, and lightweight yet sturdy. This study evaluates the physical properties of PALF-cotton yarn at three twist speeds, two total drafts, and three PALF-cotton blending ratios. The methodology of this study involves carding, drawing, and ring spinning of the PALF-cotton fibers. The process starts with cutting and opening PALF before blending it with cotton fiber using a carding machine. The finding shows that the average diameter and fineness values range from 205 μm to 458 μm and 31.2 to 67.0 tex, respectively. The study also reported that twist speed, total draft, and blending ratio affect the diameter and fineness of the yarns. In contrast, the increment of twist speed and total draft decreases the fineness and diameter of PALF-cotton yarns. Pineapple leaf fiber (PALF) shows great potential in the apparel industry. Three regression models were presented to predict the future ring-spinning process, and pineapple waste can be repurposed into valuable products, reducing overall waste.