Preparation and characterization of physical properties of Durian skin fibers biocomposite

Durian skin fibres (DSF) are cellulose-based fibres extracted from the durian peel. This paper present the physical behaviour, chemical structure and crystallinity of the fibres, as observed by environmental scanning electron microscope (ESEM), Fourier transform infrared (FTIR) and Xray diffraction (XRD). The characteristic of the natural fibers produces from durian skins are\ud similar with other types of natural fiber. The average diameter and density are 0.299 mm and 1.243 g/cm3, respectively while the crystallinity index is slightly higher than the common fibers. The properties and charecteristic of durian skin fibers are within the propertise of lignocellulosic fiber which is suitable for development of biocomposite materials

Statistical Optimization Using Response Surface Methodology for Enhanced Tensile Strength of Polyethylene/Graphene Nanocomposites

Despite having remarkable features such as low density, ease of fabrication and recyclability, linear low-density polyethylene (LLDPE) has several drawbacks like poor stiffness and low creep resistance which fortunately can be improved by incorporating with other suitable nanofillers. In this study, graphene nanoplatelets (GNPs) that are well-known for its high surface area and superior stability were selected to reinforce the polymer network of LLDPE via melt blending. During mixing processing, the rotor speed, mixing temperature and mixing time parameters are manipulated with the aids of 5-level-3-factor central composite rotatable design (CCRD) in order to determine the optimization of processing parameters in preparing LLDPE/GNPs nanocomposites. The experimental data is fitted with the statistically significant quadratic model with R2 value of 0.8601. The results showed that the tensile strength of LLDPE/GNPs nanocomposites could be extended to 24.80 MPa.  The optimum processing parameters for preparation LLDPE/GNPs nanocomposites were found to be at 101 rpm rotor speed, 139.8oC of mixing temperature and 13.2 min of mixing time, resulting in LLDPE/GNPs nanocomposites with tensile strength of 24.11 MPa. Conclusively, our study has provided a novel statistical design of experiment to obtain the optimum processing parameters in preparing LLDPE/GNPs nanocomposites

Optimizing the parameters in durian skin fiber reinforced polypropylene composites by response surface methodology

Awareness on the advantages of natural fibers stimulates the interest of researchers to use them as reinforcement in polymer composites for robust application. Therefore, investigation on optimizing the impact property of durian skin fiber (DSF) reinforced polypropylene (PP) composites was carried out to determine the effect of DSF content, fiber size and maleic anhydride polypropylene (MAPP) content. Response surface methodology (RSM) was used in the design of experiments and in the analysis of results. The optimized value for the maximum impact strength of PP–DSF composite was found at 50 wt% DSF content and fiber size range of 250–500 μm with 0 wt% MAPP. The maximum impact property for PP–DSF composite was 10.66 kJ/m2. From the analysis of variance (ANOVA), fiber content significantly affects the strength of PP–DSF composites, followed by the fiber size and MAPP content. The P-value of the model of experiment is less than 0.05 and the determination coefficient (R2) is nearly 1 which suggested that the model is significant and implies on the precision and processability in the production

Comparative adsorption mechanism of rice straw activated carbon activated with NaOH and KOH

Activated carbon (AC) was produced from rice straw via a two-step method. Potassium hydroxide (KOH) and sodium hydroxide (NaOH) were used as activating agent. The activated carbon (AC) samples were used as adsorbent to remove methylene blue (MB) from aqueous solution. Characterizations using a scanning electron microscope (SEM), BrunauerEmmett-Teller surface area (BET), and Fourier transform infrared (FTIR) spectroscopy were performed on the samples before the MB adsorption experiments. The adsorption isotherms and kinetics analyses were carried out under different conditions of pH, temperature, and MB concentration to study the adsorption efficiency of the samples against the MB solution. The adsorption kinetics of both activated carbon samples followed the pseudo-second-order model. The adsorption capacity of the KOH rice straw activated carbon towards MB achieved a maximum adsorption 588 mg/g as compared to 232 mg/g of the NaOH rice straw activated carbon. The intraparticle diffusion model indicated that the adsorption process of the activated carbon samples toward MB included the external mass transfer and diffusion of MB molecules into the adsorbents. Adsorption isotherm results for MB on the activated carbon samples fit the Langmuir isotherm, suggesting monolayer adsorption during the adsorption process

Reinforced thermoplastic natural rubber hybrid composites with Hibiscus cannabinus, L and short glass fiber – Part I: Processing parameters and tensile properties

Hybrid composite of thermoplastic natural rubber (TPNR) reinforced with Hibiscus cannabinus, L fiber (kenaf fiber: KF) and short glass fiber (GF) were prepared via melt blending method using internal mixer, at various temperatures, speed and time. TPNR matrix is a blend of polypropylene (PP), liquid natural rubber (LNR) and natural rubber (NR) at a ratio of 70 : 10 : 20. Processing parameters were determined from the tensile strength based on fiber content with 50 : 50 ratios of GF and KF. Using the optimum processing parameters, tensile test was carried out for reinforced TPNR–KF–GF hybrid composites (0–20% by volume), with and without addition of silane coupling agent and maleic anhydride grafted polypropylene (MAPP). The result of tensile strength has shown that the increasing in kenaf fiber content substantially reduced the tensile strength and modulus. Scanning electron microscopy (SEM) has shown that the composite, with coupling agent or compatibilizer, promotes better fiber–matrix interaction

The mechanical and physical properties of thermoplastic natural rubber hybrid composites reinforced with hibiscus cannabinus, L and short glass fiber

Thermoplastic natural rubber hybrid composites reinforced with kenaf and short glass fibers were compounded by melt blending method using an internal mixer, Thermo Haake 600P. Thermoplastic natural rubbers (TPNR) were prepared from polypropylene (PP), natural rubber (NR) and liquid natural rubber (TPNR) with ratio 70:20:10, which were blended using internal mixer for 12 minutes at 180�C and rotor speed 40 r.p.m. Glass fiber was treated with silane coupling agent while TPNR reinforced kenaf fiber composite is using MAPP as a compatibilizer. TPNR hybrid composite with kenaf/glass fibers was prepared with fiber content (5, 10, 15, 20 volume % of fiber). Mechanical properties of the composites were investigated using tensile test[1], flexural, impact, and hardness test and scanning electron microscope (SEM)[1]. The incorporation of the treated or untreated fiber into TPNR has result in an increment of almost 100% of flexural modulus and impact strength as compared to TPNR matrix. However, the maximum strain decreased with increasing fiber content. The optimum composition for hybrid composite is at the fiber ratio of 30% kenaf fiber and 70% glass fiber. The SEM micrograph had shown, that the composite with coupling agent or compatibilizer promote better fiber-matrix interaction

Kesan penambahan kepingan nanozarah grafin terhadap sifat mekanik dan terma hibrid komposit serabut Sansevieria-getah asli-polietilena berketumpatan tinggi

Kajian ini dilakukan untuk mengkaji kesan penghibridan kepingan nanozarah grafin (GNP) ke atas sifat mekanik, morfologi dan terma komposit Sansevieria trifasciata-getah asli-polietilena ketumpatan tinggi (STF-NR-HDPE). Pemprosesan penghibridan komposit STF-NR-HDPE dan GNP dilakukan dengan menggunakan mesin pengadun dalaman. Tahap pengisian sebanyak 20% bt. STF ke atas matriks (NR/HDPE) telah dilakukan dalam kajian ini dengan variasi GNP yang digunakan adalah antara 1-10% bt. Adunan komposit yang terhasil ditekan dengan mesin penekan panas untuk mendapatkan sampel ujian berketebalan 1 mm dan 3 mm. Sampel dinilai melalui ujian tegangan, ujian hentaman Izod, pembelauan sinar-X (XRD) dan kalorimetri pengimbasan berbeza (DSC). Kajian morfologi pula dijalankan dengan menggunakan mikroskop elektron pengimbas pelepasan medan (FESEM). Keputusan menunjukkan bahawa nilai kekuatan regangan dan kekuatan hentaman komposit menunjukkan sedikit penurunan bacaan pada permulaan penambahan amaun GNP tetapi bacaan kebanyakan komposisi kemudiannya menunjukkan peningkatan selepas 5% bt. tahap pengisian dan ke atas. Modulus tegangan pula secara umumnya menunjukkan peningkatan bacaan dengan penambahan pengisi. Analisis terma dengan menggunakan alat DSC tidak menunjukkan perubahan aliran graf yang ketara terhadap kelakuan terma bahan. Ini kerana STF adalah bahan yang mempunyai kestabilan terma yang baik