Papers by Keyword: Coir

Abstract: The purpose of this study was to determine the tensile, flexural, and impact strength of coir composites as fishing boat wall materials. The stages of this study were: (1) preparation, procurement of materials, coir treatment, composite manufacture, testing, and discussion. Before being used as a composite reinforcement, coir was soaked in an alkali solution with a concentration of 20% for 3 hours, then dried in an oven at a temperature of 90°C for 5 hours. Coir composites were made with three types, namely 20%, 25%, and 30% coir, respectively. After that, tensile, flexural, and impact test specimens were made. Based on the test, the highest tensile and flexural strengths were obtained in coir composites with a composition of 30% coir, respectively 21.04 MPa and 44.71 MPa, while the highest impact strength was obtained in a composition of 25% coir, namely 4.3 kJ/m2. It was concluded that the higher the composition of coir, the greater its strength.

Abstract: It is quite amazing that the use of 3D printing techniques, especially the Fused Deposition Modelling (FDM) has delivered such significance in terms of cost reduction, time saver features where a different variety of thermoplastic and composite materials (Biodegradable and Non-biodegradable) are well developed. Different sectors have continually developed natural organic materials that are also both structurally composite in nature. Similarly, the use of different fibers that are abundantly accessible and considered as renewable resources which can be optionally combined with other biodegradable materials is a great challenge through the use of the FDM printing method. The study aims to determine the effect of different particle size and raster angle at a certain fiber concentration which could affect the mechanical properties of the composite by developing a printable composite filament made of Polylactic Acid (PLA) and Coco Coir materials using a filament maker and FDM printer. The composite filament was fabricated and optimized using a twin-screw extruder and 3D Devo Filament maker. 3D printing of samples for mechanical testing was conducted using three (3) raster angles (45^o, 60^o, and 75^o) and various particle sizes of coco coir fiber reinforcement in the PLA matrix. Results showed that the < 74μm particle size of the coco-coir exhibited a 24% and 175% increase in tensile strength and izod impact strength compared to the pure PLA at 60^o and 75^o raster angles, respectively. Likewise, the reinforcement of <149μm particle size coco coir at 45^o raster angle contributes to an increase of 4.8% flexural and 176% compressive strength compared to pure PLA. The study concludes that there is an improvement in the mechanical properties of the PLA-Coco Coir composite at a certain particle size and raster angle in 3D printing.

Abstract: The utilization of natural fibers in composites continues to increase due to their advantages over the synthetic fiber materials especially in terms of environmental impact and costs. One of the techniques that can be used to further enhance the properties of these natural fiber reinforced composites is through fiber hybridization. In this study, salago and coir fibers were reinforced in the epoxy resin to form a new hybrid composite. The salago to coir fiber weight ratios considered in the fiber hybridization were 3:1, 1:1 and 1:3. The performance of these hybrid fiber composites were compared to pure coir fiber composite and salago fiber composite in terms of impact strength, tensile properties and flexural properties. Among the hybrid fiber composites, the fiber weight ratio of 3:1 has the highest tensile strength (33.8 MPa), tensile modulus (3.57 GPa), flexural strength (44.2 MPa) and impact strength (42.3 J/m). It was found out that the addition of coir to this hybrid fiber composite improves the tensile strength by about 21.1 % as compared to the salago fiber composite. On the other hand, the addition of salago fiber to this hybrid fiber composite resulted to a higher tensile modulus (43.4 %) and impact strength (25.5 %) than the coir fiber composite. Moreover, the thermal analysis of the composites revealed a peak degradation temperature at around 370 °C which is associated to the decomposition of cellulose, hemicellulose and epoxy resin.

Abstract: Over the last decades composite materials, plastics and ceramics have been the dominant emerging materials. The volume and number of applications of composite materials have grown steadily, penetrating and conquering new markets relentlessly. So everybody is concentrating on new materials which will be strong enough, less weight, recyclable with reduced cost. Hence all the researchers are concentrated on the composite materials which have all the above properties. The present work is concentrated on coconut coir fiber and Rice husk reinforced polyester hybrid composites. The composites specimen was fabricated with various weight percentages of natural fibers namely coconut coir (20%, 15%, 10%, and 5%) and Rice husk (15%, 10%, and 5%) combined with CamElect 3321 resin using hand lay-up method. So to obtain new composite materials different proportions of coconut coir and Rice husk is added and the mechanical properties such as Tensile strength, Flexural Strength and Impact test were carried out for the samples cut from the fabricated composites specimen to the dimensions as per ASTM standard. With the increasing percentage of the reinforcements the performance of the material is improving. The tensile strength increases with the increase in coir reinforcement percentage and flexural strength increases with the increasing in percentage of the rice husk and the impact strength of the material gets boost with equal proportional percentage of coconut coir and rice husk reinforcement.

Abstract: Permanent formwork building system is a method that uses the formwork as a contributor to the load bearing capacity of the structure. This study characterized the proposed foamed composite structural insulated panel (CSIP) with coir for load bearing wall application in low rise construction. The percentage of coir in foamed concrete that could significantly increase the compressive and flexural strength of the panel considering the effect of coir to the workability of the foamed concrete were determined. The results showed that the samples with 0.5% coir had the maximum increase in its compressive and flexural capacity and further addition of coir decreases its capacities. The results also showed that it could carry the required design loads. Moreover, using Euler’s buckling equation for the effect of slenderness, the panel could be used as exterior wall for a height of 2m, 3m, and 4m and as interior wall for a height of 2m and 3m. It can be concluded that the proposed panel could be used as a load bearing wall in low rise construction.

Abstract: Polypropylene (PP), a versatile polymer finds application in many sectors. However, it has low impact strength.To overcome this draw back elastomer is added, which results in improved impact property at the expense of decreased tensile strength. To improve this fillers are added. However some fillers also improve impact strength. In this work only fillers have been used to get balance of properties in PP. Knowledge of crystallization of PP is important for processing of PP. In this work the effect of hybrid fillers on PP has been studied on the isothermal and non-isothermal crystallization kinetics of PP. The fillers used are coir and talc.

Abstract: The influence of chitosan impregnation on the tensile and flexural strength of the short coir fiber reinforced polyester composites were studied in this investigation. The chitosan fillers were dispersed in polyester matrix, and laminates were prepared by reinforcing coir fibers in chitosan –polyester matrix. The composites were fabricated by varying filler content, fiber content and fiber length in three levels and their influence on tensile and flexural strength of the composites were studied. The composites with fiber length 30 mm, filler content 4% and fiber content 25% showed better values tensile (23 MPa) and at the same time the flexural strength (28MPa) of the composite was observed to be better with fiber length 30 mm, filler content 4 % and fiber content 25%.

Abstract: The main objective of this investigation was to study the properties of composites of polypropylene (PP) containing different proportions (20, 40 and 60% wt%) of coir short fiber (natural vegetable fiber) without treatment of fibers, for use in products by injection with applications in the automotive industries, construction and other segments. Samples were prepared in a only stage using a high intensity thermokinetic mixer (K-Mixer). Additives were used in the mass fraction of 3 wt% compatibilizer (PP-g-MA), 2.2 wt% processing additive and 0.12 wt% thermal antioxidant. The composites were characterized by tensile test according to ASTM D638-10. The surface properties of the polymeric matrix with additives were studied by determining the contact angle (CA) in a sessile drop tensiometer and the carbonyl index (CI) by Fourier-transform infrared spectroscopy (FTIR). Thermal properties of the PP and the composition were evaluated by thermogravimetric test, and the interface of the fiber and the matrix in the composites were evaluated using images from scanning electron microscopy (SEM). The CA analysis showed that the PP matrix with additives has become less hydrophobic and the FTIR and the CI that there was a better stabilization of the PP with additives. There was an increase in thermal stability of the composites for all fiber content, which was up to 15 °C above PP for coir fiber composites. In the Young's modulus values showed that the inclusion of fibers reinforced the polymeric matrix and increased the stiffness of the composites, especially in composites containing 60% (wt%) in which the values were ~1.7 times greater than the polypropylene. Images of micrographs showed the interaction of the fiber in the matrix and that despite the hydrophilic character of the fibers and hydrophobic character of the PP, the composites showed non-homogeneous interfaces. These findings confirm the feasibility of using high level of coir fiber in polypropylene composites even without pretreatment of the fibers and the preparation of samples by injection.

Abstract: It is well known fact that vibrations contribute to excessive wear, fatigue failure and other premature failure of machine components. Thus, various methods have been applied to control these vibrations. One of the commonly used is vibration absorber. The aim of this paper is to explore the potential of epoxy reinforced natural fibers as an alternative material for vibration absorber. Both mechanical properties and dynamic characteristic of the composites are investigated through tensile test and transmissibility test, respectively. Two types of natural fibers were selected for the study; coconut coir and pineapple leaf. The results show that the tensile modulus of composites increases with the increase of fiber content, although the strength was found decreases. This reduction indicates an ineffective stress transfer between the fiber and matrix. From the tensile test result, 20 vol% of pineapple leaf fiber was found to be the optimum fraction, in which afterward was employed for fabrication vibration absorber. Meanwhile, from the transmissibility test, it was noticed that when base excitation increases, the resonance peak and attenuation frequency were changed to the lower value. The fixed-fixed end beam with attached composite vibration absorbers showed that the resonance amplitude of the beam decreased significantly. More absorbers attached on the beam produce better result in attenuating the global structural vibration.

Abstract: Natural fibres are fibre that can be directly obtained from an animal, mineral, or vegetable sources. Recently natural materials are becoming a good alternative for synthetic material as they provide good health to a greener environment. This aim of this study to investigate and compared the acoustic characteristics of three natural fibres; Kenaf fibre (Hibiscus Cannabinus), Ijuk fibre (Arenga Pinnata), and Coconut coir fibre, where each material is qualified for acoustical absorption. During the processing stage, each fibre is reinforced with 60:40 ratio of pure latex separately. The fibres are then compressed after the pure latex treatment into circular samples, of 28 mm and 100 mm diameters respectively. The thickness of each sample is fixed at 50mm. The acoustical performances were evaluated by using an impedance tube instrument. This study also investigates the effect of air gap of 10mm and 50mm in the sound absorption performance. The results show that, all the three fibres have reached an optimum level of sound absorption value of more than 0.7. The frequency peak value of Kenaf is obtained in a range of 700 Hz – 800 Hz, while for coconut coir is at 1000 Hz – 1075 Hz frequency range. Only Ijuk has obtained the highest frequency range of 3200 Hz – 3400 Hz. The results demonstrate that these three fibres are a promising light and environment-friendly sound absorption material as they are ready to replace the common synthetic fibre.