Rice Husk Fiber Research Articles

Mechanical properties of hybrid glass fiber/rice husk reinforced polymer composite

The world today is experiencing a significant global warming problem. One of the causes of the problem is due to the use of excessive and uncontrollable material. Therefore, replacing the material with more environmental friendly is a challenging task, especially from wasted natural materials such as rice husk (RH) fiber. The aim of the study is to investigate the mechanical properties from composites made by reinforcing bi-directional glass fiber and RH short fiber with epoxy resin. Total of fibers content for each sample was 30 wt% and 70 wt% for epoxy resin. The weight distributions for RH fiber were ranging from 5 wt%, 10 wt% and 15 wt%, meanwhile 25 wt%, 20 wt% and 15 wt% for bi-directional glass fiber. The arrangement of fibers were alternate layers and hand lay-up for fabrication of hybrid composite. The best combination of hybrid composite was 5 wt% of RH fiber and 25 wt% of glass fiber with tensile strength value 215.42 MPa, tensile modulus 1.8 GPa, flexural strength 275.51 MPa and impact strength 447.19 J/m. It was indicated that the decreasing trend on its mechanical properties when the content of RH fiber exceeds 5 wt%.

Utilization of Rice Husk Cellulose as a Magnetic Nanoparticle Biocomposite Fiber Source for the Absorption of Manganese (Mn2+) Ions in Peat Water

Rice husk (RH) is an agricultural waste that contains cellulose. Rice husk fiber (RHF) can be used as a source of fiber in the manufacture of magnetic nanoparticle biocomposite. The purpose of this study is to synthesize and characterize magnetic nanoparticle biocomposite used as an adsorbent and evaluate its performance on the adsorption of Mn2+ ions and Total Suspended Solid (TSS) in peat water. Rice husk fiber was delignified to eliminate lignin levels. Furthermore, the biocomposite was made through the solvothermal method with and without the addition of hexanediamine. The products produced are two types of adsorbents, namely magnetic nanoparticle biocomposite with an amino group (RHB-MH) and rice husk fiber biocomposite without an amino group (RHB-M). These biocomposites were used to adsorb Mn2+ ions in peat water. Evaluations were carried out at pH 5, 6, 7, and 8 with an optimum adsorption time of 60 minutes. The solutions at the time of adsorption were evaluated to determine the optimum conditions of the adsorption process carried out. The observation of magnetic nanoparticle biocomposite based on the analysis of Scanning Electron Microscopy (SEM) shows magnetic nanoparticles formed on the surface of rice husk fiber with a diameter of 30-50 nm. X-Ray Diffraction (XRD) analysis showed that the delignification of rice husk increased Crystallinity Index (CrI) by 64.98% and reduced silica content by 78%. Fourier Transform Infra-Red (FT-IR) spectrometer show absorption peak at 570 cm-1 for Fe-O bonds and Fe3O4 peak around 1627 cm−1, indicating the presence of N-H bending. The optimum condition for Mn2+ adsorption was achieved at pH 5 and 60-minutes duration with an adsorption capacity of 54.7 mg/g and 190.78 mg/g for RHB-M and RHB-MH. The TSS reduction achieved the effectiveness of 60.2% and 90.3% for BSP-M and BSP-MH, respectively.

Improvement of Rice Husk/HDPE Bio-Composites Interfacial properties by Silane Coupling Agent and Compatibilizer Complementary Modification.

Composites using agricultural and forestry residues as raw materials with potentially high-performance, multifunctional and biodegradable ecological advantages, are viewed as very promising for new-generation lightweight and low-cost bio-based sustainable building materials. At present, the research on wood-plastic composite materials is relatively mature. However, it is still a challenge to effectively use other biomass and improve the interface of the high-polymer compound system. Herein, we proposed a simple and effective method to enhance the interfacial adhesion properties of rice husk fibre and High Density Polyethylene (HDPE) composites by the silane coupling agent KH-550 and compatibilizer Maleic anhydride grafted polyethylene (MAPE) with complementary modification. It was found that the coupling agent KH-550 cross-linked with the hydroxyl group on the husk fibre surface and solidified with the high polymer by –NH–, –C=O– functional group generation. Compatibilizer MAPE strengthened the two phases by covalently bonding with an ester linkage and lowered the roughness of the cross-section of the composites. Meanwhile the modification enhanced the dispersibility, and mechanical properties of the husk-high polymer compound system, the bending and flexural strength were improved by 11.5% and 28.9% with KH-550, and MAPE added, respectively. The flexural strength of the composites increased by 40.7% after complementary modification. Furthermore, the complementary modification treatment reduced the hydrophilic hydroxyl groups and increased the molecular chain to improve the water-resistance, elastic modulus and toughness of the composite. This study prepared a bio-composite, which is expected to expand the use of agricultural and forestry residues as an extension of wood-plastic composites.

Energy behavior assessment of rice husk fibres reinforced polymer composite

Natural fibre composites, possess characteristics that are beneficial towards the environment and ecosystem, completely biodegradable, renewable, offer strength and reliability of the material properties, and enhance economic development because of its ability in replacing synthetic composites. One of them refers to rice husk, which is a non-timber source that is easily available from agricultural wastes. Hence, rice husk fibres were selected as fibre-reinforced composites, while polypropylene as matrices in this research. Rice husk composite (RHC) specimens were produced via injection molding process. The composite composition was fixed at 35% of fibre content. The cycle tests were conducted to obtain cyclic properties by adhering to specifications outlined in ASTM D3479. Servo-hydraulic machines were used for five different stresses with constant amplitudes of R=0.1, R=0.3, and R=0.5 of S75, S80, S85, S90, and S95 to determine the stress effects on energy dissipation and fatigue life of the material. The results indicated that there was increment in energy loss for the increasing fatigue life in every cycle. This shows that with the addition of natural fibres in composites, the material exhibited viscoelastic behaviour, in which energy loss was represented by matrix cracks and broken fibres.

Tailoring Structural and Optical Properties of Composite Glass with Rice Husk Fibre (RHF) as Additive Materials

This paper reports the effect of additional of rice husk fibre (RHF) with various sizes ranging from 63μm, 125μm and 250μm on the structural and optical properties of glasses. A series of glass with composition of 69.50TeO2 – 20ZnO – 10Na2O – 0.50Er2O3 – (x)0.2%RHF (x = 63μm, 125μm, 250μm) are synthesized by using melt-quenching technique. XRD pattern shows the nonexistence of sharp peak reflect the amorphous nature of glass without RHF content. However, an addition of RHF in glass matrix shows the appearance of sharp peaks signifies the contribution of cristobalite due to the incorporation of rice husk. SEM image of glass containing 125μm RHF illustrates the glass surface morphology. The respective EDX spectra of glass containing 125μm RHF verify the elemental traces of carbon, oxygen, sodium, zinc, tellurium, aluminium, silicon, copper, calcium and erbium. The variation in absorption coefficient of glass with additional of different sizes of RHF are observed due to the lowering value of α.

Tuning Optical and Structural Properties of Composite Glass: Effect of Rice Husk Fibre

Tuning optical and structural properties of composite glass due to the effect of rice husk fibre are examined. A series of glass with composition of 69.5TeO2-20ZnO-10Na2O-0.5Er2O3-(x)0.2RHF where x is rice husk fibre in weight percentage with three distinctive sizes of 63 μm, 125 μm and 250 μm are prepared following melt-quenching technique and characterized systematically. UV-Vis spectra displayed nine absorption bands centered at 380, 410, 445, 489, 520, 545, 650, 799 and 975 nm corresponding to the transitions of Er3+ originate from ground state to excited states. The direct and indirect band gap is found to lies in range of 3.296 to 3.410 eV and 2.958 to 3.174 eV, respectively. Urbach energy lies in the range of 0.145 to 0.181 eV. SEM images illustrates the fractures surface due to porosity of glass samples and elemental traces verify the appearance of C, O, Na, Zn, Te, Au, Al, Si, Er and Ca elements.

Optimisation of bio-based building materials using image analysis method

Wetting of bio-based mortars — the affinity of the biofibres and earth to the water — can have a strong impact on the flow, but the microscale physics and macroscopic consequences remain poorly understood, not helping in the material optimisation. This research analyses the influence of casting on biofibres dispersion in bio-based insulation materials at the macro-level and evaluate changes on hygrothermal behaviour if fibres and casting change. Earth-based blocks reinforced with 3% weight content of barley straw, hemp shiv and rice husk fibres were produced with 5 and 4 cm thickness using two casting methods. The 5 cm blocks were unstabilised and compacted; the 4 cm blocks were moulded and stabilised with gypsum and air lime. The approach is to implement a developed method of image analysis to elucidate the inherently 2D pore-scale mechanisms and help explain the striking macroscopic displacement patterns that emerge. The results indicate that production variables have a significant directionally dependent impact on the physical properties of cast bio-based materials. This means that the Image analysis can be used for quality control towards the optimisation of the bio-composites. Thermal conductivity and ultra sound velocity are affected by fibres distribution inside bio-based materials. The shape of ultra sound distribution from direct and indirect methods enhance the anisotropy of the bio-based materials with different composition and casting methods.

Compatibilized recycled polymers/clay as a matrix for rice husk composites: mechanical and physical properties

The growing green technological trend towards waste utilization and cost reduction has gained the industrial attention in the use of agricultural waste as a value added filler material. This research addresses a simple fabrication of greenly bionanocomposites made from polyethylene (rHDPE), recycled polyethylene terephthalate (rPET), nanoclay and rice husk (RH), with and without ethylene-glycidyl methacrylate (E-GMA) or maleic anhydride polyethylene (MAPE) compatibilizer, using a two-step twin-screw extrusion followed by hot/cold pressing. Results showed the positive effect in elongation at break and impact strength upon the reinforcement of nanoclay with the aids of compatibilizer as compared to the neat polyolefin blend. By adding RH, the flexural properties were found to increase remarkably up to 3.6 times than the blend matrix. It was found that the addition of compatibilizer, especially E-GMA, lowered the water absorption and thickness swelling of bionanocomposites. Scanning electron microscopy confirmed the improved compatibility of nanoclay with polymer blend upon the addition of compatibilizer. It can be concluded that the synergy effects of hybrid reinforcements of rice husk fibre and nanoclay in the recycled polymer blend have achieved while maintaining environmental appeal.

Effect of Reinforcing Fillers and Fibres Treatment on Morphological and Mechanical Properties of Typha-Phenolic Resin Composites

This study estimates the potential using of typha australis (t. australis) as reinforcing element in composite materials based on plant fibres as way of enhanced for this invasive plant. Composite materials based on t. australis, bamboo and rice husk fibres were prepared with phenolic resin and their properties compared in order to evaluate this invasive plant in relation to the commonly used fibres in composite materials. Scanning Electronic Microscopy shows similarity in the morphologic structure of t. australis and bamboo fibres. The failure mode is typically the same for all composite materials when fibres or system undergo the same treatment. The 3-point bending tests exhibit mechanical characteristics in the same range for different composites materials, for example the Young modulus for t. australis, bamboo and rice husk composites without any modification are estimated at 1.92, 2.04 and 2.00 GPa respectively.

Extrusion processing of a high fibre loading of agrowaste in recycled polyolefin biocomposite

A high loading rice husk fibre (RHF) incorporated polyolefin blend of recycled polyethylene high-density/poly(ethylene terephthalate) (rPEHD/rPET) biocomposite was produced through extrusion and hot/cold press process. Interfacial modification of biocomposites was conducted through alkalization (sodium hydroxide solution) of fibres, compatibilization (using E-GMA) and/or coupling agent (MA -g-PE) to improve the interaction between components and the homogeneity of materials blending. Alkalization of fibres had improved the impact strength of biocomposites. The compatibilization and coupling effects on immiscible rPEHD/rPET blend and recycled polymer/RH filler, respectively, had led to an enhancement of mechanical performance and morphological stability. Scanning electron microscope micrograph revealed the improved matrix–matrix and filler–matrix interaction through interfacial modification. This investigation had shown that RHF mixed well with rPEHD/rPET/RHF to produce eco-friendly biocomposite products.

Influence of nanofibers prepared from rice husk on the properties of natural rubber

ABSTRACT Different concentrations of rice husk fibres have been mixed with natural rubber to study the effect on the properties of rubber mixtures and vulcanisates. Cellulose nanofibers were added in different concentrations up to 100 phr. The aim was to improve the mechanical properties of the composite, swelling resistance, and rheological properties. The research studied microstructure of prepared composites and properties of rubber mixes and vulcanisates, using transmission electron microscopy (TEM) and X-ray diffraction. Rice husk fibres derived from treating the husk with sodium hydroxide followed by careful drying and grinding in ball mill were used as filler in natural rubber formulations. These treated fibres improved the tensile strength up to an optimum concentration (20 phr) and then started to decrease in effect. A marked improvement in the modulus of elasticity and hardness of rubber mixtures also occurs.

Effect of Nano-Filler Content and Fiber Treatment on the Characteristics of Gamma-irradiated Rice Husk-Epoxy Particleboard Composites.‎

In this study, both untreated and treated rice husk fibers with a silane coupling agent are incorporated with epoxy resin to prepare particleboard composites. The effect of different ratios of nanoclay 5%, 10%, 15%, and 20% (by the weight of the polymer) on the physicomechanical properties of the prepared particleboard composites is investigated. The results show that the flexural, and impact strengths as a function of mechanical properties getting better with increasing nanoclay content up to 10%. While the addition of nanoclay to the samples decreases the water absorption percentage. This decrease is almost constant with nanoclay (%). In addition, the effect of different doses of gamma-irradiation on the properties of both untreated and treated rice husk-epoxy particleboard composites that containing 10% of nanoclay is also discussed. The results show that the irradiated specimens at a dose of 10kGy achieved a good enhancement in mechanical properties whereas the water absorption percentage as a physical property decreases at a dose of 10kGy and starts to increase with increasing gamma irradiation doses. TGA, and SEM are carried out to confirm the data obtained.

Effect of Gamma-Irradiation on Properties of Polymer/Fibrous/Nanomaterials Particleboard Composites

This investigation aimed to study the role of different contents of nano-slag, as well as various doses of gamma-irradiation on physical and mechanical properties of rice husk-polyvinyl chloride particleboard composites. Equal proportions of rice husk fibers and polyvinyl chloride polymer were used. The treatment of rice husk fibers with silane coupling agent showed a significant improvement in both mechanical and physical properties of the prepared particleboard composites as compared to those containing untreated rice husk fibers. Moreover, the partial replacement of polyvinyl chloride with different percentages of nano-slag namely 5, 10, 15, and 20% by the weight of polymer manifested a good effect on the properties of the resulting particleboard composites precisely at 10%nano-slag. In addition, the effect of different gamma-irradiation doses on the properties of the particleboard composite specimens that contain 10% nano-slag showed an enhancement in the physical (thickness swelling %) and mechanical (flexural strength, and hardness) properties. In addition, the results elaborated that the irradiated particleboard composites had a good thermal stability.

Effects of rice husk fibers on the properties of mixed-particle-size fiber-reinforced polyvinyl chloride composites under soil accelerated aging conditions

In this article, rice husk fiber/polyvinyl chloride composites were prepared and analyzed. The optimal composition of mixed-particle-size fiber-reinforced composites was determined through orthogonal experimentation. The physical, mechanical, and thermal properties of the mixed-particle-size fiber-reinforced composites were compared to unprocessed (100 mesh) rice husk fiber/polyvinyl chloride composites. The surface microscopic appearances of the unprocessed and final composites were observed via laser microscope. Long-term accelerated soil aging caused micro-cracks to appear on the surfaces of the composites. Interfacial adhesion was observed via scanning electron microscopy. The results indicated that mixed-particle-size fibers can better fill interfacial gaps, leading to strong interfacial adhesion. Furthermore, the addition of mixed-particle-size fibers improves the soil aging resistance of composites. The hardness, flexural strength, impact strength, and first onset pyrolysis temperature (after 0 days) increase from 50 HRR, 35.2 MPa, 3.19 KJ/m2, and 258.5°C to 55 HRR, 39.4 MPa, 3.86 KJ/m2, and 261.2°C, respectively. However, the mass loss rate and thickness expansion rate (after 21 days) decrease from 2.9% and 0.79% to 2.21% and 0.74%, respectively. In general, the addition of mixed-particle-size fibers improves the ultimate properties of composites under soil aging conditions.

Manufacturing of superabsorbent membranes of PVA and rice husk fibres reinforced with nanosilica for agricultural and horticultural applications

ABSTRACTNovel superabsorbent membranes (SMs) consisting of polyvinyl alcohol (PVA), cellulose nanocrystals (CNCs) originated from rice husk (RH), nanosilica, glutaraldehyde and glycerine (G) were manufactured by a compression moulding process. RHs were used to isolate pure CNCs via mechanical and chemical treatments. RHs were used to improve water retention. These SMs were characterised by Fourier-transform infrared spectroscopy, scanning electron microscopy, mechanical testing and differential scanning calorimetry. SMs showed a greater equilibrium swelling capacity than neat cross-linked PVA. Moreover, the water transport mechanism of all SMs was found to follow Fickian diffusion. SMs exhibited good pH-dependent swelling reversibility and high-water retention capacity, making them more efficient water retention materials. The biodegradability of SMs was evaluated under environmental changes. The biodegradability of SMs was evaluated against environmental changes. The SM was also investigated for antimicrobial activity against pathogenic bacteria such as Candida albicans (fungus), Bacillus subtilis (Gram-positive), Staphylococcus aureus (Gram-positive), Proteus vulgaris (Gram-negative) and Erwinia carotovora (Gram-negative). SMs have been found to act as a useful water reservoir, which may make it useful in agricultural applications.Abbreviation: Novel superabsorbent membranes (SMs) consisting of polyvinyl alcohol (PVA), cellulose nanocrystals (CNCs) originated from rice husk (RH), nanosilica (NS), glutaraldehyde (GLA) and glycerine (G) were manufactured by a compression moulding process. RHs were used to isolate pure CNCs via mechanical and chemical treatments. RHs were used to improve water retention. These SMs were characterized by Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Mechanical Testing and Differential Scanning Calorimetry (DSC).

Effects of pretreatment on the soil aging behavior of rice husk fibers/polyvinyl chloride composites

The application of rice husk fibers (RHFs) to reinforce wood plastic composites has received appreciable attention. However, good interfacial adhesion is important for actual applications. Pretreatment methods can reduce the hydroxyl groups in plant fibers in order for them to bond with the plastic matrix. In this research, RHFs were pretreated by four methods: hydrothermal treatment (HT), microwave treatment (MT), alkali treatment (AT), and benzoylation treatment (BT). The effects of the four pretreatment methods on aging behavior of RHFs/polyvinyl chloride (PVC) composites was studied with simulated soil-accelerated aging conditions. Accelerated-soil aging caused the physical and mechanical properties of the composites to deteriorate. The ultimate performance of the composites was improved by the pretreated RHFs. The effectiveness ranking of the pretreatment methods was: benzoylation-treated RHFs reinforced PVC (BRRP) > alkali-treated RHFs reinforced PVC (ARRP) > hydrothermal-treated RHFs reinforced PVC (HRRP) > microwave-treated RHFs reinforced PVC (MRRP) > untreated RHFs reinforced PVC (URRP).

Strength, microstructure, and thermal conductivity of the insulation wallboards prepared with rice husk fiber and recycled concrete aggregates.

This paper intends to evaluate the influence of content of rice husk fiber and cementitious materials on mechanical properties and thermal conductivity of thermal insulation wallboards. Thermal insulation wallboard contained different mass of rice husk fiber was prepared when the weight of cement, fly ash, cellulose ether, naphthalene superplasticizer, and recycled concrete aggregates was equal. Scanning electron microscopy (SEM) shows the internal structure of the insulation wallboards is very dense. Compared to thermal conductivity of blank group (0.9600 W/m·°C), B2 (0.1997 W/m·°C) and C2 (0.1810 W/m·°C) measured by the DRCD-3030 intelligent thermal conductivity tester can meet certain engineering requirements. Average compressive strength, flexural strength, and thermal conductivity of wallboards decreases with content of rice husk fiber increasing when other materials mass are the same. Under the same conditions of curing time and rice husk content, average compressive and flexural strength increase with the increase of the amount of cementitious material.

Rice Husk Fiber Magnetic Nanoparticle Biocomposites: Preparation and Characterization

The synthesis of biocomposites from rice husk (RH) fiber and magnetic nanoparticle was made by solvothermal reaction. Rice husk dried was blended to small size (60 mesh), then through delignification process to eliminate lignin by 1% w/v NaOH solution. Delignified rice husk was put into hydrothermal reactor, afterward was carried out by one-pot solvothermal at 200 °C for 6 h in the presence of 1,6-hexanediamine, FeCl3.6H2O and ethylene glycol. The process was produced two types of biocomposites, without amino group (RHB-M) and with amino group (RHB-MH). The characterization results shown by FE-SEM, magnetic nanoparticle have been formed on the surface of RH fiber with diameter size around 30–50 nm could be obtained. X-Ray Diffraction (XRD) analysis showed treatment of ED delignification was increased crystalinity index (CrI) about 16.77% and reduced silica content about 78%. The iron content may affect the adsorbent by enhanching the high-adsorption of sorbent capacity for reactivity toward a wide range of organic pollutan.

Combination of ground rice husk and polyvinyl alcohol fiber in cementitious composite

In this study, ground rice husks (GRH) in combination with polyvinyl-alcohol (PVA) fiber were used to produce low-cost and high-quality hybrid cementitious composites. Different amounts of GRH (2.5, 5.0, 7.5 and 12.5% in weight of cement) were added to the concrete. The work presented in this paper provides an insight into the use of an agricultural waste as effective additive in cement based materials. The properties of resultant cementitious composites including density, water absorption, flexural behavior and compressive strength were investigated. The results have shown that incorporation of ground rice husk in combination with PVA fiber can be effective in improvement of the flexural properties of cementitious composite. The study explored the effectiveness of this type of agricultural waste as a beneficial material in fine aggregate concrete materials.

3D printing of biodegradable parts using renewable biobased materials

The paper presents ways of utilising the additive manufacturing process 3D-printing using renewable biobased materials, with a focus on adapted packaging for sensitive components. This application provides an attractive scenario for sustainable production and the re- or upcycling of waste material such as wood flour, rice husk or miscanthus fibre. Packaging of prototypes with sensitive or filigree structures or made of fragile materials is currently difficult, because standardized packages are often not suitable and cost for adapted packages are high. Within this study, CAD-data based adapted packaging made of renewable raw materials is addressed. The 3D-printing process was modified for using conditioned biobased fibre and a special binder. Furthermore, a software tool was developed to create adapted packaging designs by using the individual part geometry.In this way and in combination with AM processes, sustainable and biodegradable packaging for complex components can be generated within a short time. The manufactured packaging is conform to the demands of packaging for fragile goods and can be produced just-in-time.