Composites and nanocomposites
Linda Gouissem
Abstract
This study explores the development of high-density polyethylene (HDPE) composites reinforced with stearic acid-treated expanded perlite (TEP) to examine their thermal, mechanical, and processing properties. The composites were fabricated using a plastograph at 200°C, incorporating perlite concentrations ...
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This study explores the development of high-density polyethylene (HDPE) composites reinforced with stearic acid-treated expanded perlite (TEP) to examine their thermal, mechanical, and processing properties. The composites were fabricated using a plastograph at 200°C, incorporating perlite concentrations from 5% to 20% by volume. The effects of stearic acid (SA) treatment and perlite content were analyzed through SEM, melt flow index (MFI), tensile and impact testing, and thermal analysis (DSC, TGA, and Vicat softening temperature). SEM analysis revealed that untreated perlite exhibited a highly porous structure, while HCl treatment induced fragmentation. At 5% SA, perlite particles were well dispersed with a thin coating, whereas at 10% SA, the coating was more pronounced, leading to agglomeration. The MFI increased with perlite loading, reaching 12.3 g/10 min at 20% perlite, compared to 8.88 g/10 min for neat HDPE. Mechanical testing showed that the elastic modulus increased by 36% (786 MPa) at 5% perlite, dropped to 460.8 MPa at 15%, and rose again to 707.7 MPa at 20%, suggesting structural reinforcement. Moderate perlite content (5-10%) preserved ductility, while higher concentrations (15-20%), especially with 10% SA, increased brittleness due to reduced interfacial adhesion. Thermal analysis showed a slight decrease in melting temperature and a slight increase in crystallization temperature with the addition of treated perlite, while thermal stability improved and the Vicat softening temperature remained unchanged. These results highlight the potential of SA-treated expanded perlite as a viable alternative to conventional fillers, offering a balance between stiffness, ductility, and thermal resistance. The developed composites are promising for light weight and cost-effective applications in energy management and construction.
Composites and nanocomposites
Ali Yakoub Alkhair; Emiru Yidnekachew Melesse; Irina Anatol'evna Kirsh; Yulia Aleksandrovna Filinskaya; Izabella Sergeevna Tveritnikova; Oleg Igorevich Mihryachev
Abstract
Bio-composite from linear low-density polyethylene (LLDPE) with lysozyme, mixed lysosome and glucose oxidase enzymes was synthesized through the melt extrusion system, respectively. The aim of this work was evaluation and characterization of the effect of lysosome, mixed lysosome and glucose oxidase ...
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Bio-composite from linear low-density polyethylene (LLDPE) with lysozyme, mixed lysosome and glucose oxidase enzymes was synthesized through the melt extrusion system, respectively. The aim of this work was evaluation and characterization of the effect of lysosome, mixed lysosome and glucose oxidase enzymes on the mechanical, water vapor transfer rate, and structural appearance of the Bio based LLDPE composite films. Along this line, 50 g of LLDPE pellets incorporated with 1%, 5%, and 10% (w/w) of lysozyme alone, mixed lysosome and glucose oxidase were examined, apparently. Pure LLDPE was used as a control. Over all, biocomposite with 5 and 10%(w/w) of mixed lysosome and glucose oxidase enzymes did not result in good outcome and not even enough for characterization. The surface structure of biocomposites was examined through the digital microscopy for identify dispersion of enzymes inside the LLDPE matrix and at higher concentration (10w/w%) dense and large surface are formed. However, good dispersion and reinforcing activity of enzymes in the LLDPE matrix was noticed with small concentration of lysosome (1, and 5w/w%) enzymes. The mechanical strength and elongation at break of biocomposite composite films were found to increase with small concentration (1 and 5 w/w%), but decrease with increasing of enzyme concentration. Averagely, the WVTR showed increase as the enzyme concentration increased. Besides, the Fourier-transform infrared spectroscopy (FTIR) was used to determine structural configuration of the enzymes in LDPE matrix; single sharp stretching breaks at 570 cm-1 with 1, 5 and 10 wt.% was corresponded to the existence of enzyme bands. All in one, the addition of lysozomes and glucose oxidase in small concentration has high potential in development of biocomposite relative to the traditional plastic composites.
Composites and nanocomposites
Reza Naghdi; Tahereh Nejat
Abstract
The ever-increasing environmental constraints over waste disposal led us to study the feasibility of valorizing bagasse/ polypropylene composites via nanosilica and mercerization treatments. Water absorption and thickness swelling of the nanocomposites improved due to the barrier properties of nanosilica ...
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The ever-increasing environmental constraints over waste disposal led us to study the feasibility of valorizing bagasse/ polypropylene composites via nanosilica and mercerization treatments. Water absorption and thickness swelling of the nanocomposites improved due to the barrier properties of nanosilica particles. FTIR spectra revealed decreased hydroxyl groups as well as carbonyl groups disappearance after alkali treatment. Except for impact strength, the combined nanosilica-mercerization treatment could enhance the mechanical performance of the biocomposites. Thermogravimetric analysis showed higher degradation temperatures and residual char yields after the combined nanosilica-mercerization treatment. Furthermore, differential scanning calorimetry indicated that the individual mercerization and nanosilica treatments had no distinct effect on the thermal performance of the composites, whereas the combined treatment brought about marked improvements in the given properties, e.g; melting and crystallization temperatures and crystallinity rate. The present study introduces a novel technique to valorize a totally waste-based bagasse/ polypropylene composite material holding a promising potential for various industrial applications.
Simulation & Modeling
Aamir Mustafa Shaikh; Pravin R. Kubade
Abstract
Polymers can be natural or synthetic and are largely used in several applications due to their versatile properties. Polymers can vary widely in their properties and applications, and they are a fundamental part of our everyday life. Polypropylene (PP) is a thermoplastic polymer from the polyolefin family. ...
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Polymers can be natural or synthetic and are largely used in several applications due to their versatile properties. Polymers can vary widely in their properties and applications, and they are a fundamental part of our everyday life. Polypropylene (PP) is a thermoplastic polymer from the polyolefin family. It is among the most widely used plastics in various automotive and packaging industries. Although PP is widely used in commodity range, still its applications are restricted in niche areas due to lack of toughness which can be improved by incorporation of rubbery materials or fillers. Graphene (G) is one of the nanomaterials used to strengthen polypropylene. Graphene is recognized for its outstanding thermo-mechanical properties, making it a highly desirable material in various fields of science and technology. Benefits gained by incorporation of graphene nanoparticles into polypropylene are studied by researchers. In this study, a finite element analysis is performed which shows the mechanical behaviour of PP and G using ANSYS, which is one of the most powerful finite element analysis (FEA) softwares that can help to perform such simulations to understand stress, strain, deformation of components before actual experimentation. The bending load of 100 N and 1400 N in vertical z-direction are applied for 100% PP model, 100% G model and 50% PP+50% G model and the linear part of stress-strain curve is captured in this analysis.
Composites and nanocomposites
Shahryar Malekie; Mohammad Amin Hosseini; Ahmadreza Abiz; Fatemeh Bolourinovin; Suffian Mohamad Tajudin
Abstract
This research aims to determine and quantify the radiation shielding characteristics of High Density Polyethylene/Tungsten Oxide composite (HDPE/WO3) including the linear attenuation coefficient (µ), mass attenuation coefficient (µ/ρ), half-value layer (HVL) and tenth-value layer (TVL) ...
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This research aims to determine and quantify the radiation shielding characteristics of High Density Polyethylene/Tungsten Oxide composite (HDPE/WO3) including the linear attenuation coefficient (µ), mass attenuation coefficient (µ/ρ), half-value layer (HVL) and tenth-value layer (TVL) for photons at various energies using Geant4, XCOM, and experiment. Thus, HDPE was chosen as the polymer matrix. Then, the samples at various concentrations of WO3 nanoparticles, including 0, 1, 2, 3, 4, 5, 6, and 9.5 wt%, different graphene oxide (GO) wt% namely 0, 0.25, 0.5, and 1 wt%, and linear low-density polyethylene (LLDPE) at 10, and 20 wt% were fabricated. NaI (Tl) scintillation detector was used to measure the shielding quantities using the 201Tl, and 99mTc sources at three energies of 135, 140, and 167 keV. The experimental results demonstrated that the addition of GO and LLDPE to the HDPE matrix resulted in a more uniform samples. Incorporating 20% LLDPE into the HDPE polymer matrix for the 99mTc resulted in an 18% rise in µ compared to pure HDPE. Finally, experimental results revealed a comparatively good agreement with the Geant4 and XCOM simulations.
Olefin polymerization and copolymerization
Tingting Yang; Ao Li; Yawei Qin; Jin-Yong Dong
Abstract
Polypropylene is one of the most widely used synthetic resins, which is mainly synthesized with Ziegler-Natta catalysts. In this paper, the functionalized Ziegler-Natta catalyst is applied to prepare high-performance polypropylene. A new way to synthesize functionalized Ziegler-Natta catalysts is to ...
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Polypropylene is one of the most widely used synthetic resins, which is mainly synthesized with Ziegler-Natta catalysts. In this paper, the functionalized Ziegler-Natta catalyst is applied to prepare high-performance polypropylene. A new way to synthesize functionalized Ziegler-Natta catalysts is to dope with inorganic nanoparticles. The MgCl2/TiCl4/BMMF catalysts doped with halloysite nanotubes were prepared and applied to synthesize polypropylene containing less than 200ppm halloysite nanotubes. It is found that doping nanotubes in Ziegler-Natta catalyst has little impact on the structure, composition and activity of the catalyst, and polypropylene with high isotactic degree and molecular weight was synthesized with the functionalized Ziegler-Natta catalyst. Halloysite nanotubes are found to be dispersed in polypropylene in the form of individual nanotube, forming percolated network in the polymer melt effectively. Moreover, the polypropylene containing halloysite nanotubes exhibited better mechanical and thermal resistance properties as compared with conventional polypropylene, and the thermo-oxidative properties of which do not deteriorate as the introduction of nanotubes. This research provides a facile way to relieve the contradiction between the high activity of catalyst and high content of nanoparticles during the preparation of polyolefin nanocomposites by in-situ polymerization, and a new idea to prepare polyolefin nanocomposites by in-situ polymerization.
Structure and property relationship
Leila Latreche; Samira Maou; Lokmane-Taha Abdi; Tahir Habila; Yazid Meftah
Abstract
Polypropylene (PP) is a strong, tough, crystalline thermoplastic material with high performance. Because of its diverse thermo-physical and mechanical properties, it is utilized in a wide variety of disciplines. In this study, the impact of free quenching on the thermo-physical characteristics of PP/calcium ...
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Polypropylene (PP) is a strong, tough, crystalline thermoplastic material with high performance. Because of its diverse thermo-physical and mechanical properties, it is utilized in a wide variety of disciplines. In this study, the impact of free quenching on the thermo-physical characteristics of PP/calcium carbonate (CaCO3) composites was examined. Three distinct heating procedures were used. First, composites were cooled from their melting phase temperature to ambient temperature. Second, composites were cooled from 130°C to a pre-determined and controlled temperature (T: 0°, 20°, 30°, 40°, 50°, 60°, 70°, 80°C). Third, composites were temperature-tested using annealing. The findings suggest that the elongation-at-break and impact strength may be improved following an initial quenching process from the melting phase to ambient temperature. On the other hand, a second quenching process at 0°C produces superior results, and a correlation between mechanical and thermal characteristics is noted; however, while these qualities are increased, others, such as flexibility, density, Vicat softening temperature (VST), and heat distortion temperature (HDT) are negatively impacted.
Composites and nanocomposites
Slimani Mohammed; Ahmed Meghezzi; Yazid Meftah; Samira Maou
Abstract
Date palm tree leaf-reinforced polymer composites have important advantages, such as sustainability and low-cost. In the present study, ternary blend composites of polyvinyl chloride (PVC), low-density polyethylene (LDPE), and acrylonitrile butadiene rubber (NBR) copolymer (LDPE/PVC: C0, LDPE/PVC/NBR:C1) ...
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Date palm tree leaf-reinforced polymer composites have important advantages, such as sustainability and low-cost. In the present study, ternary blend composites of polyvinyl chloride (PVC), low-density polyethylene (LDPE), and acrylonitrile butadiene rubber (NBR) copolymer (LDPE/PVC: C0, LDPE/PVC/NBR:C1) as well as reinforced composites with 10, 20, and 30 wt.% of alkali treated date palm fiber (TDPF) (C2, C3 and C4 respectively) were fabricated using a melt blending extrusion process. TDPF and the NBR copolymer were used to improve the interfacial bonding, compatibility, and thermo-mechanical properties of the composite, yielding the highest tensile strength of 32 MPa for the composite containing 10 wt.% TDPF. Moreover, the morphological analysis showed that the incorporation of the NBR copolymer enhanced the compatibility of the blend. Mechanical tests revealed that the hardness of the TDPF/PVC/LDPE/NBR composite increased in the order C2 (450 MPa) < C3 < C4 (540 MPa). In addition, the flexural and tensile moduli of the composite increased with increasing TDPF content, with the highest values (534 and 1585 MPa, respectively) observed for composite C4. Thermal analysis revealed increased Tonset and T10% values, indicating an improved thermal stability of the composite. This study clearly demonstrates that the (DPF/PVC/LDPE/NBR) composites can be used in various high-tech engineering applications, which require excellent properties.
Composites and nanocomposites
Zahra Ranjbarha; Javad Mokhtari-Aliabad; Parviz Aberoomand-Azar; Seyed Amin Mirmohammadi; Mohammad Saber-Tehrani
Abstract
In the present work, the ability of wood-plastic composite containing high density polyethylene and wood powder as a recycled material to remove methylene blue cation pigment was studied. The effect of some important parameters such as pH, adsorbent amount and contact time was investigated. Adsorption ...
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In the present work, the ability of wood-plastic composite containing high density polyethylene and wood powder as a recycled material to remove methylene blue cation pigment was studied. The effect of some important parameters such as pH, adsorbent amount and contact time was investigated. Adsorption efficiencies for methylene blue were maximized at alkaline pH. Adsorption capacity increased with increasing adsorbent amount and contact time. The value of R2 in Langmuir model was equal to 1 and the separation factor for 0.5 and 1 g of adsorbent was 0.09 and 0.1, respectively. Given that the methylene blue adsorption data were more consistent with the Langmuir isotherm model, it can be stated that the wood-plastic composite probably has uniform adsorption surfaces and the adsorption process occurred in a homogeneous system on the adsorbent surface. Based on the results of this study, it was observed that this composite is a suitable adsorbent for removing methylene blue from aqueous solutions and used as a purifying agent in the decolorization of effluents containing pigments. This adsorbent is recyclable and cost-effective for dye removal from textile industry wastewater.
Composites and nanocomposites
Hamed NazarpourFard
Abstract
Polyvinylpyrrolidone (PVP) composites based on rice husk (RH), rice husk carbon (RHC, i.e., black rice husk ash (BRHA)) and rice husk ash (RHA, i.e., white rice husk ash (WRHA)) were prepared separately through solution casting method. Similar composites were made using polystyrene (PS) through the same ...
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Polyvinylpyrrolidone (PVP) composites based on rice husk (RH), rice husk carbon (RHC, i.e., black rice husk ash (BRHA)) and rice husk ash (RHA, i.e., white rice husk ash (WRHA)) were prepared separately through solution casting method. Similar composites were made using polystyrene (PS) through the same protocol. The carbon and ash obtained from this type of rice husk were obtained via pyrolysis at 300 and 600 °C, respectively, for 1 hour. The effects of these additives on the spectroscopic characteristics of polymers were verified by examining the infrared (FT-IR) and X-ray diffraction (XRD) spectra of the prepared composites. The resulting showed a remarkable difference between the spectra of parent polymers and the corresponding composites. Changes in peak width and 2θ parameters (observed in XRD patterns) revealed that PVP possesses better interactions with RHC, while PS has better interactions with RHA. Due to the high hydrophilicity of PVP, some investigations were accomplished on the hydrophilic properties of PVP samples. Polystyrene did not reveal detectable water vapor absorption (WVA), thus this experiment was not carried out for PS samples. Eventually, it was disclosed that there are significant discrepancies between the hydrophilic properties of PVP and its composites. In the other word, the WVA decreased from 290% for parent PVP to 210% for PVP-RHC composite.
Composites and nanocomposites
Tohid Abdolahzadeh; Jalil Morshedian; Shervin Ahmadi
Abstract
Researchers have studied the possibility of various polymer composites for radiation shielding applications. Lightness and non-toxicity of these materials are their significant advantages compared to Pb base traditional and common shields. In this research, polyethylene (HDPE)-based composites for shielding ...
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Researchers have studied the possibility of various polymer composites for radiation shielding applications. Lightness and non-toxicity of these materials are their significant advantages compared to Pb base traditional and common shields. In this research, polyethylene (HDPE)-based composites for shielding against X-ray radiations were prepared by utilizing several weight fractions of the nano tungsten oxide, bismuth oxide, and barium sulfate, which were decorated on nanographene oxide (10, 15, 20, and 25 wt%). The linear and mass attenuation coefficient values of samples were investigated experimentally with an X-ray tube at radiology energy ranges and estimated theoretically by using MCNP code (Mont Carlo Nanoparticle program). Results illustrate that by increasing the nanoparticles content, the linear attenuation coefficient parameter and the absorbed dose values increased dramatically. The shielding efficiency of the prepared samples has been shown by measuring the HVL values. Furthermore, the effect of sample thicknesses on the attenuation properties of nanocomposites was studied in this research. The morphological properties of the samples were evaluated with SEM. The collected results showed that the particle size of the nanoparticles used has a uniform dispersion in the polymer matrix. The mechanical properties of nanocomposite samples were characterized by DMTA and tensile test. Nanocomposites containing 20% and 25% of tungsten oxide and bismuth oxide particles reached to 88% and 90% dose absorption, respectively.
Composites and nanocomposites
Raid Banat; Malek Aljnaid; Manal Al-Rawashdeh
Abstract
Mechanical and physical properties of various weigh percentages (0% - 40%) of olive pomace flour (OPF)-loaded linear low density polyethylene (LLDPE) in the presence of 0%, 5% and 10% coupling agent (C) were formulated and studied. Extrusion and hot press processing techniques were used to fabricate ...
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Mechanical and physical properties of various weigh percentages (0% - 40%) of olive pomace flour (OPF)-loaded linear low density polyethylene (LLDPE) in the presence of 0%, 5% and 10% coupling agent (C) were formulated and studied. Extrusion and hot press processing techniques were used to fabricate OPF/LLDPE composites. Tensile stress at yield increased by 20% with the increasing of the filler loading up to 20%; and marginally increased in the presence of the C. Whereas, the decline in the tensile strain at yield of the polymer composite improved with the increase in the C content. The modulus increased from 631 MPa for the neat LLDPE to 680, 808 and 700 MPa for the composites filled by 5%, 10% and 20% filler content, respectively. Whereas, a decrease in the given modulus (550 MPa) was observed at 40% filler loading. The modulus has shown a successive improvement upon the addition of the C with values not less than 800 MPa. The impact strength decreased with the increase in filler loading from 119 kJ/m2 for the neat LLDPE to 81, 43, 27 and 16 kJ/m2 for the 5%, 10%, 20% and 40% OPF/LLDPE samples, respectively. On the contrary, 10% C addition improved the impact strength of the composite by two folds in the case of 10 - 40% filler inclusion. The scanning electron microscopy (SEM) illustrations proved the mechanical performance of various bio-composite formulations. Water absorption of the bio-composite increased with the OPF loading, from 0.73% for the neat LLDPE to 2.6% for 40% OPF-filled polymer composite, and decreased upon increasing the C content with an average of 1.4% for all composites. Formulated by mixing cellulosic-based material OPF and LLDPE, the bio-composite demonstrated compatible physical properties and can be used as an already available cellulosic filler for the bio-composite materials.
Composites and nanocomposites
Afshar Alihosseini; Amin Hedayati Moghaddam
Abstract
In this work, the effects of operative parameters on CH4, CO2, O2, and N2 membrane gas separation for poly (4-methyl-1-pentane) (PMP) membrane modified by adding nanoparticles of TiO2, ZnO, and Al2O3 are assessed and investigated. The operative parameters were type and percentage of nanoparticles, and ...
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In this work, the effects of operative parameters on CH4, CO2, O2, and N2 membrane gas separation for poly (4-methyl-1-pentane) (PMP) membrane modified by adding nanoparticles of TiO2, ZnO, and Al2O3 are assessed and investigated. The operative parameters were type and percentage of nanoparticles, and cross membrane pressure. The membrane permeability and selectivity were selected as the responses and indexes of separation process performance. To design the experimental layout, design of experiment methodology (DoE) techniques were used. Further, the separation process was modeled and simulated using artificial intelligence (AI) methods. So, a robust black-box model based on radial basis function (RBF) network was developed and trained with the ability for predicting the performance of membrane process. The developed model could simulate the process and predict the permeability with R2-validation of 0.9. Finally, it was found that addition of nanoparticles and increasing the operative pressure had positive effects on membrane performance. Maximum permeability values for O2, N2, CO2 and CH4 were 181.58, 52.09, 550.85, and 54.26, respectively. The maximum values of validation-R2 of optimum structure for CO2/N2 and CO2/CH4 selectivity were 0.8697 and 0.7028, respectively.