Journal of Applied Research in Chemical-Polymer Engineering

Abstract Research subject: In this study, Fe₃O₄ nanoparticles were first synthesized through a controlled co-precipitation method. Subsequently, a uniform silica coating was formed on the surface of iron oxide nanoparticles via the Stöber process using tetraethyl orthosilicate (TEOS) as the silica precursor, resulting in core–shell Fe₃O₄@SiO₂ nanoparticles with a stable and well-organized structure. The obtained nanoparticles were then functionalized with a molecularly imprinted polymer (MIP) to produce a targeted and selective adsorbent for the removal of zinc ions (Zn²⁺) from aqueous solutions. The concentration of Zn²⁺ ions was determined using Inductively Coupled Plasma (ICP) analysis.
Research approach: To comprehensively investigate the physical, chemical, and structural characteristics of the synthesized nanoadsorbent, various analytical techniques were employed, including transmission electron microscopy (TEM), field-emission scanning electron microscopy (FE-SEM), dynamic light scattering (DLS), vibrating sample magnetometry (VSM), thermogravimetric analysis (TGA), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FT-IR).
Main results: The characterization results confirmed the formation of a coherent structure with uniform particle size distribution, good thermal stability and successful incorporation of active functional groups on the nanoparticle surface. The adsorption performance of the nanoadsorbent for Zn²⁺ ions was evaluated by studying the effects of various operational parameters, including adsorbent dosage, contact time, pH and initial metal ion concentration. Optimized results revealed that under the conditions of an adsorbent dosage of 16 mg, pH=7, an initial concentration of 0.45 mmol L⁻¹, a solution volume of 50 mL, and a contact time of 21 min, the removal efficiency of Zn²⁺ ions reached 96%, indicating the high performance of the adsorbent (107.55 mg/g). Also, isotherm studies demonstrated that the adsorption process followed the Langmuir model, suggesting a monolayer adsorption mechanism. Furthermore, kinetic analysis showed that the experimental data fitted the pseudo-second-order model, confirming that chemisorption was the dominant rate-controlling mechanism. In addition, the synthesized nanoadsorbent exhibited excellent magnetic separability, allowing for easy recovery from the aqueous solution. It also demonstrated high reusability over multiple adsorption-desorption cycles without significant loss in its adsorption performance. Therefore, the designed adsorbent can be considered a stable, efficient, and environmentally friendly system, offering a promising approach for the effective treatment of industrial wastewater containing heavy metal ions.

Abstract Research subject: Cellulosic nanomaterials, including cellulose nanocrystals, cellulose nanofibers, and bacterial cellulose, have attracted significant attention as reinforcing agents in epoxy matrices due to their low density, high mechanical strength, suitable elastic modulus, and renewable nature. However, the inherent hydrophilicity of cellulose nanoparticles and their poor interfacial adhesion with epoxy resins impose critical limitations on the mechanical and thermal performance of epoxy nanocomposites. Consequently, surface modification of cellulosic nanomaterials has emerged as a key strategy to enhance interfacial compatibility and improve the overall properties of epoxy-based nanocomposites.
Research approach: This study presents a comprehensive review and analysis of research published between 2023 and 2025, focusing on various surface modification techniques for cellulosic nanomaterials. These techniques include silane treatments, hydrophobic coatings, esterification reactions, and other chemical modifications. The primary objective of these approaches is to reduce the hydrophilicity of cellulose nanofibers, enhance interfacial adhesion between the reinforcing phase and the epoxy matrix, and promote uniform dispersion of nanomaterials within the nanocomposite structure.
Main results: The results of this study demonstrate that surface modification of cellulose nanoparticles significantly enhances their interfacial interactions and dispersion within the epoxy matrix, leading to a noticeable increase in the onset and peak thermal degradation temperatures, a reduction in the thermal degradation rate, and a measurable increase in char residue at elevated temperatures. Improved dispersion and reduced agglomeration of nanofibers result in substantial enhancements in mechanical properties, including tensile strength, elastic modulus, and stiffness, along with improved fracture behavior and effective inhibition of crack propagation. Quantitative analysis indicates that the surface modification method, functional group chemistry and density, nanofiber loading level, and dispersion uniformity play decisive roles in optimizing both thermal stability and mechanical performance. Overall, this work provides a systematic, quantitatively driven engineering framework for the design of durable, high-performance epoxy nanocomposites suitable for high-temperature and demanding industrial applications.

Abstract This review article focuses on recent advancements in enhancing the mechanical, thermal, electrical, and corrosion-resistant properties of epoxy resin through the incorporation of surface-modified zinc oxide nanoparticles. The main objective of this review is to highlight the role of nanoparticle surface modification and weight fraction on the performance of epoxy nanocomposites and to provide a comprehensive overview of the findings reported in previous studies. In this review, scientific articles and experimental studies on epoxy nanocomposites containing zinc oxide nanoparticles were systematically analyzed. Selected studies were evaluated based on criteria such as the type of nanoparticle surface modification, dispersion and mixing methods, nanoparticle weight fraction, and the effects of these parameters on the mechanical and thermal properties of the epoxy matrix. Additionally, the findings related to hybrid nanocomposite structures and their synergistic effects were summarized. The review indicates that uniform dispersion of nanoparticles in the epoxy matrix improves interfacial adhesion, prevents stress concentration and crack propagation, and consequently enhances the overall strength and durability of the material. Most studies suggest that low nanoparticle loadings (0.25–1 wt.%) promote better dispersion and improved mechanical properties, whereas higher loadings may cause particle agglomeration and reduced performance. Surface modification of nanoparticles with silane or amine groups enhances compatibility with the polymer matrix, improves stress transfer, and increases thermal stability. Furthermore, recent studies show that hybrid nanocomposite structures create synergistic effects, simultaneously enhancing multiple performance characteristics. Overall, the incorporation of surface-modified nanoparticles into epoxy resin demonstrates significant potential for developing advanced materials in electronics, photonics, marine, medical, and aerospace applications.

Abstract Research subject: In this study, a conductive sensitive layer composed of polybenzimidazole (PBI) and carbon nanotubes (CNTs) was designed and fabricated via electrospinning for the detection of volatile organic compounds (VOCs)—(methanol, ethanol, isopropyl alcohol (IPA), acetone—and water vapor.
Research approach: This study employed an experimental approach. In the first stage, various processing parameters—such as flow rate, voltage, and needle-to-collector distance—were optimized to enable the fabrication of uniform fibers with nanometric diameters. Subsequently, the fibers were deposited onto an interdigitated gold-on-glass electrode (IDE) as the sensor base to form the sensitive layer of the sensor. Finally, the dynamic response of the fabricated sensor was evaluated using a custom-built measurement system developed by the research group.
Main results: Optimal electrospinning conditions were established at a flow rate of 0.5 cc h⁻¹, an applied voltage of 24 kV, and a nozzle-to-collector distance of 15 cm, enabling the production of uniform nanofibers, as confirmed by scanning electron microscopy (SEM). Brunauer–Emmett–Teller (BET) analysis revealed a fiber specific surface area corresponding to 18.23 m² g⁻¹. Dynamic sensing experiments demonstrated strong sensor responses toward alcohols and acetone, with response intensity correlating inversely with alcohol polarity from methanol to IPA. The sensors exhibited an exceptionally short response time (< 10 s), attributed to the nanofibrous architecture of the sensing layer, which promotes rapid vapor diffusion and access to active sites. Furthermore, the response trends and selectivity toward target vapors were analyzed in the context of thermodynamic parameters, including the Flory–Huggins interaction parameter.

Abstract Contamination of water and soil with heavy metals poses serious risks and threats to human health and the environment, and therefore finding an effective solution to remove these metals is very necessary. In this research, magnetic nanoparticles MnFe₂O₄ @ SiO₂ functionalized with N-phosphonomethyl aminodiacetic acid with core-shell structure were synthesized. These nanoparticles were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, (TGA) thermal gravimetric analysis, transmission electron microscope (TEM), and (VSM) vibration sample magnetometer. The performance of this synthetic nanoadsorbent for removing Cr (VI), Cu (II) ions from aqueous solutions was evaluated by various parameters such as adsorbent amount, contact time effect on adsorption rate and pH effect. The results show that the adsorption efficiency increases with raising pH (2.5-5) and the best adsorbent performance in the adsorption process of Cr ((VI) and Cu (II) ions at pH 7 was observed. The amount of R in the Freundlich adsorption diagram of copper ion is higher than the Langmuir isotherm. As a result, the adsorption of copper ions on the adsorbent follows the Freundlich adsorption equation. In addition, the amount of R in the Freundlich adsorption diagram for chromium ion is higher than the Langmuir isotherm. Therefore, the absorption of chromium ions on the adsorbent follows the Freundlich adsorption equation. In conclusion, a high n value indicates a favorable and effective absorption in the Freundlich equation. The adsorption data were analyzed by the Langmuir and Freundlich isotherm model. In addition, the recyclability and reuse of the adsorbent was investigated. The results show that no significant reduction in adsorbent activity is observed.

Abstract Research subject: Polycarbonate/acrylonitrile butadiene styrene alloy is one of the most widely used polymer alloys in the world, which has become very widespread due to the excellent properties and characteristics of these alloys as well as other advantages. However, it seems that strengthening the properties and efficiency of these alloys can increase their scope of application. Typically, polymers have a high resistance to the passage of electricity. In recent years, increasing the electrical conductivity or reducing the electrical resistance of polymers by using conductive nanoparticles has received much attention.
Research approach: For this purpose, first, alloys of polycarbonate and acrylonitrile butadiene styrene were prepared by melt mixing method and were tested and evaluated in terms of physical and mechanical properties, thermal properties and behavior of the melt. Next, by adding nanographene to the best alloy, the electrical, mechanical and morphological properties of nanocomposites were investigated. In order to increase the electrical conductivity of nanocomposites, different amounts of nanographene (1, 2 and 3%) were used.
Main results: By increasing the amount of polycarbonate, tensile strength and modulus, flexural strength and modulus, and HDT of the alloys increased. The results showed that the alloy with 68% polycarbonate generally has better properties than other alloys, so this alloy was considered as the polymer base of nanocomposites. The results of the mechanical test show an increase in the tensile strength and tensile modulus of the samples with an increase in the percentage of nanoparticles. Also, the examination of the electrical resistance of nanocomposites showed that in all samples, nanographene has been able to reduce the electrical resistance of the polymer to a very significant extent. By examining the mechanical and electrical properties of the samples, it was determined that the Percolation threshold of nanoparticles is equal to 2%. The FE-SEM images of the nanocomposites showed that the graphene nanoparticles were well dispersed in the polymer matrix and no traces of clumps or clusters resulting from the accumulation of nanoparticles were observed.

Abstract Hypothesis: One potential method for improving nanocomposite mixed matrix membranes is through the use of nanoparticles and compounds containing hydroxyl and carboxyl groups, which may aid in the penetration of CO₂ gas. In this study, we investigated the selectivity and permeability of a polyether block amide/polyvinyl alcohol (Pebax/PVA) nanocomposite membrane containing magnesium oxide (MgO) nanoparticles. Previous research has shown that the addition of MgO to the Pebax/PVA matrix can increase CO₂ permeability by creating an intermolecular space.
Methods: Prepared a Pebax/PVA nanocomposite membrane with a weight ratio of 80:20, containing 10% MgO nanoparticles, through a solution casting method. Evaluated the performance of the Pebax/PVA/MgO nanocomposite membrane for separating CH₄ and CO₂ gases using various tests.
Findings: Characterized the membranes through Fourier transform infrared (FTIR), X-ray diffraction (XRD), and field emission scanning electron microscopy (FESEM) tests. FESEM images showed increased surface roughness with the addition of nanoparticles, and the nanoparticles were well dispersed within the polymer matrix. XRD analysis indicated that MgO nanoparticles had more interaction with PVA chains than with Pebax chains, and peaks at 42° and 62° regions were formed due to the placement of MgO nanoparticles among the polymer chains. We studied various parameters, including polyvinyl alcohol and MgO nanoparticle content, pressure, and temperature, as independent variables and examined their effects on the permeability of CH₄ and CO₂ gases. We measured the permeability of the constructed membranes and found that the addition of MgO significantly increased the permeability of CH₄ and CO_2.

Abstract Research subject: Poly (2-oxazoline) (PEOX) polymers are a family of synthetic macromolecules with biodegradable and biocompatible features. They resemble polypeptides in structure and therefore, have recently taken put to use in drug delivery. Nonetheless, these polymers suffer from relatively low thermal and mechanical performance and thus are reinforced with nanoparticles as nanocomposites. The molecular details of the reinforcement mechanism of PEOX have not yet been elucidated.
Research approach: This research work was done to reach an understanding on interaction of 2-oxazoline-based polymers with 2D nanoscale reinforcements and to shed light on the mechanism of reinforcing the respective nanocomposites. To this end, conformation and dynamics of poly (2-ethyl-2-oxazoline), as a known representative member of this family, near a functionalized graphene nanosheet were studied via classical molecular dynamics for a period of 10 ns. The effects of various temperatures and polymer chain lengths on polymer conformation and dynamics were assessed.
Main results: Molecular dynamics snapshots exhibited effective interaction of the polymer chain with the graphene nanosheet leading to adsorption, whereby conformation and dynamics of the chain underwent transition. The adsorbed polymer chain adopted a flat, folded arrangement parallel with the graphene plane. Also, the gyration radius was found to increase, when the polymer chain approached the graphene nanosheet. Pair correlation function curves revealed that the adsorption correlation length was on the order of the repeating unit end-to-end distance. Mean-square-displacement of the polymer chain decreased as it moved towards graphene. An increase in temperature led to a change in structure and dynamics of the adsorbed polymer chain.

Abstract Research subject: Biodegradable compounds with high mechanical and thermal properties are one of the intersting research topics. Polylactic acid is an aliphatic polyester with high biodegradability and flexibility. It, however, suffers from several weaknesses such as high permeability to water vapor and gases, low glass transition temperature, poor thermal stability and brittleness which can be improved by the incorporation of nano-scale fillers giving rise to bionanocomposites. The aim of this study was to investigate the effect of the simultaneous incorporation of cellulose nanocrystals and nanosilver on the mechanical, thermal and water vapor permeability behavior of polylactic acid-based films.
Research approach: Polylactic acid films and their bionanocomposites containing different levels of cellulose nanocrystals (0.01, 0.03 and 0.05 g) and nanosilver (0.01 g) were prepared by solution casting method. To improve compatibility and miscibility of the polymer, cellulose nanocrystals were reacted with acetic anhydride and modified. FTIR spectroscopy, tensile test, thermal properties (DSC), migration test and antibacterial properties were used to study the properties of the samples. The water vapor permeability of the samples were also measured.
Main results: The addition of cellulose nanocrystals, increased the glass transition temperature (T_g) and melting point (T_m) of the samples. The presence of cellulose nanocrystals increased the tensile strength and modulus of elasticity of the bionanocomposite relative to pure polylactic acid. With the addition of cellulose nanocrystals, permeability was reduced by about 25%. As the amount of cellulose nanocrystals increased, the swelling and water absorption of the samples increased significantly. The migration rate of the samples also decreased after the addition of nanocellulose.

Abstract Research subject: Solar cells has gained a great attention as a green, renewable and cheap energy resources. To overcome the challenging technical problems and improve their competitiveness with silicone solar cells, the design, synthesis and development of new materials with engineered band gap energies has found an undeniable importance.
Research approach: Herein, the synthesis of a polymer with donor-acceptor structure based on polyaniline grafted to ZnO nanoparticles at one end and naphthalene moiety at the other end of chains, and investigation of their chemical structure, composition, morphology, optical and electrochemical properties is reported. The chemical structure of the materials were analyzed by FT-IR and ¹H NMR spectroscopy. The organic and inorganic contents of materials were determined by thermal gravimetric analysis (TGA) and atomic absorption spectroscopy (AAS) techniques. The morphology and size of nanoparticles were observed by scanning electron microscopy (SEM). The optical and electrical band gap energy of the samples were measured by ultraviolet visible-diffuse reflectance (UV-Vis-DRS) spectroscopy and cyclic voltammetry (CV) diagrams.
Main results: The chemical structure of designed materials has been successfully confirmed by the results of FT-IR and ¹H NMR spectra. TGA and AAS analysis have indicated that the synthesized final material has contained about 10% of ZnO and 90% of organic parts including toluene-2,4-diisocyanate, 2,4-diaminotoluene, polyaniline and naphthalene groups. An almost highly uniform spherical nanoparticles with sizes about 70 nm has been observed by SEM images. UV-Vis-DRS spectroscopy and CV diagrams have revealed that by grafting ZnO nanoparticles and naphthalene moiety to the polyaniline chain ends, the optical and electrical band gap energy of the sample were lowered to 1.19 and 0.95 eV, respectively. It was concluded that the grafted groups to chain ends has increased the length of conjugated system, lowering the energy level of lowest unoccupied molecular orbital (LUMO) and increasing the energy level of highest occupied molecular orbital (HOMO). Detailed analysis of CV diagrams has indicated that the effect in lowering of LUMO has been a bit more pronounced than the increasing of HOMO energy level.

Abstract Research subject: The use of hydroxyapatite nanoparticles (HAp) in traditional polymers as reinforcing agent has been reported. While there are a limited number of reports regarding the effect of HAp morphology on the mechanical properties of the polymeric matrix, no research on this effect on supermolecular polymers has been reported so far. This study investigates the hypothesis that incorporation of unidirectionally grown HAp nanoparticles (rod-like nanoparticles, rHAp) into supramolecular polycaprolactone (SPCL) leads to the synthesis of a new bioactive construct.
Research approach: For this, rHAp nanoparticles were first synthesized by microemulsion method and then functionalized with 2-ureido-4[1H]-pyrimidinone (UPy) groups. Moreover, PCL was functionalized and converted to supramolecular structures by reacting the hydroxyl terminal groups with UPy groups. Finally, SPCL/rHAp nanocomposites were synthesized by solution casting method and their structure and properties were examined using attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy, scanning electron microscopy (SEM), universal testing machine and simulated body fluid (SBF).
Main results: According to the results, microemulsion is an efficient procedure for the synthesis of rod-like nanoparticles with high phase purity. On the other hand, based on the results, it is possible to functionalize these nanoparticles with UPy. Tensile test showed that by incorporation of these modified nanoparticles into SPCL, a significant increase in both elastic modulus and tensile strength can be observed. In fact, while the initial PCL was a waxy solid, modification with UPy and then incorporation of modified nanoparticles made it an elastic material. Finally, the obtained results indicated high bioactivity of supramolecular nanocomposites compared to the sample without filler. Therefore, supramolecular SPCL/rHAp nanocomposites with bioactive properties and dynamic character can be used as a suitable replacement for bone tissue defects.

Abstract Plant fibrous suspensions require electrostatically cationic polymers to provide proper and strong structures during papermaking. The charge bearing naturally and synthetically polymers (Polyelectrolytes), are considered as the most chemicals used in cellulosic products mills, due to improvement in the fibrous suspension and network properties. For this, cationic acrylamide polymer (CPAM) and anionic nano cellulose (ANC) were added individually and in combination forms into the fibrous suspension recycled from brown packaging papers. Compared to the blank sample without any the polymeric additive, the polymeric contained suspensions and networks revealed improvements in fibrous suspension properties; i.e., retention, freeness and the solid materials loss during the network formation; and in the fibrous dried network, include density, tensile and burst strengths. Individually application of each CPAM and ANC increased the suspension retention (productivity) as 8% and 2%, resp. Fibrous suspension freeness and loss materials content continuously increased and decreased up to 47%, respectively that could provide significant technologically and economically benefits. Paper density (+5%), tensile (+17%) and burst (+27%) properties improved drastically compared to the blank. But, tear strength of fibrous network decreased (-4%) which could be attributed to the network higher fines contents and retention, originated from the acrylamide polyelectrolyte flocculation effect. Individually application of ANC also enhanced suspension retention, network density, tensile and burst strengths and declined network tear strength with lesser suspension freeness and loss. Anionic nature, high specific surface area and huge hydrogen bonding potential of ANC are the main reasons of the obtained results. ANC post addition to CPAM contained suspension resulted in tear reduction, but higher suspension retention and freeness, together with higher density, tensile and burst strength of cellulosic network.

Abstract Research subject: Nanomaterials are substances that, because of their size, can easily penetrate small pores and apply their impact. Nanofluids can allow appropriate wettability change in the reservoir rock, therefore, an accurate understanding of the behavioral mechanisms of these nanofluids is important in changing the wettability. This is because if there is no proper understanding of these mechanisms, they may exhibit the opposite behavior and cause damage to the reservoir. In previous research, CuO / TiO2 / PAM nanocomposite was synthesized and mechanistically introduced.
Research approach: In this study, in continuation of the previous study, the behavioral and mechanism study has been investigated in a more accurate and documented manner, and spectral absorption tests, chemical flooding, and relative permeability diagrams confirm the effectiveness of enhanced oil recovery results of this nanocomposite. In carbonate rocks due to the positive surface charge of the rock and the negative charge of the nanocomposite, adsorption of nanomaterials in a double electrode layer state has been suggested as the dominant mechanism of wettability change. In sandstone rocks due to the charge coincidence of rock surface and nanomaterials which are both negative, the mechanism of disjoining pressure was the dominant mechanism of wettability change. To prove the abovementioned behaviors 200 ppm concentration of nanofluid was analyzed by spectroscopy method of adsorption analysis to validate the attraction forces of the nanocomposite with carbonate rocks and repulsion forces with sandstones.
Main results: Dynamic chemical flood tests were performed to confirm the effectiveness of this material in increasing oil production and showed 8.5% and 6.35% increase in oil production for carbonate and sandstone lithologies, respectively. Relative permeability diagrams showed an intersection point in the carbonate system with a 10% increase in water saturation and an intersection point in the sandstone system with a 12% increase in water saturation and the behavioral effect of the material at the studied concentrations.

Abstract Optical properties of graphene oxide and poly methyl methacrylate nanocomposite was investigated in this paper. Initially, graphene oxide was prepared from the oxidation of graphite powder by a strong acid by Hummers-Offemane method. Then identification, purity determination and particle size were obtained by using infrared spectroscopy, X-ray diffraction and scanning electron microscopy. The average size of graphene oxide nano particles was estimated about 38.4 nm using the XRD technique. So nano composites of graphene oxide based on poly methyl methacrylate were prepared by the co-precipitation method as an optical sensor element. Nano composites were identified and characterized by FE SEM, EDX, XRD and FT IR analyzes. To investigate the optical properties of the specimens, UV-vis spectro photometry and reflective spectrometer were used. For three samples of the poly methyl methacrylate nano composite containing nano -graphene oxide, the values ​​of the color parameters b *, a * and L * were obtained that were prepared in the same conditions. Then the black index of the Westlanchr('39')s ratio was calculated. The average blackness index calculated was 3.7 for this nano composite. The study of UV-vis spectra in the region of 400-1100 nm for this nano composite showed that in the 400 - 700 nm regions the light transmission of UV light is approximately zero. Therefore, the results showed that the use of graphene oxide in the PMMA matrix improves the nano composite coating properties against UV waves and nano oxide graphene gives better shades of black color compared to other fillers and pigments.

Abstract Research subject: Polymer nanofibers have attracted much industrial interest over the past decade. In general, these fibers are suitable for a variety of applications including medical applications, insulation, capacitors, advanced aerospace technologies, and so on. Specifically in aerospace technology, the used materials must be thermally stable with suitable electrical conductivity. However, many of these polymer nanofibers suffer from low temperature degradation and low electrical conductivity, limiting their use in many potential applications. Graphite has unique properties such as high conductivity and high thermal stability. This exceptional material can be included as a nanoparticle in polymer nanofibers to modify electrical and thermal properties.The aim of this research was to investigate the effect of addition of graphite nanoparticle on thermal and electrical propertiesof polymer fibers.
Research approach: For this purpose, polyvinyl alcohol 72000 (PVA) as a non-conductive polymer and graphite nanoparticles were used. Polyvinyl alcohol-graphite nanofibers were synthesized method by electrospinning technique under optimized parameters. The optimum conditions for the electrospinning process were: PVA concentration of 8%, applied voltage of 22 Kv, flow rate of 10 ml and tip/collector distance of 20 cm.
Main results: Scanning electron microscopy (SEM) studies showed that produced PVA fibers were smooth, continuous without any bead, with a diameter of about 350 nm. The PVA / graphite nanofibers were also smooth but much thinner (about 200 nm) than PVA fibers at the same processing parameters. Moreover, X-ray patterns of PVA/graphite nanofibers include peaks of graphite particles in the structure and slso the suppression of crystallinity. According to the results of 4 point probe teste, by increasing weight percentage of graphite in the fibers, electrical conductivity increased up to 0.5 . The thermal behavior of PVA nanofibers after mixing with graphite was also investigated by differential calorimetry analysis (DSC) and TGA. It was demonstrated that PVA / graphite nanofibers are thermally stable up to 300 ° C.

Abstract Research subject: In this research we studied the anti-corrosion properties of epoxy coating containing anti-corrosion pigment zinc phosphate with hydrophobic nano silica with different percentage also for determine the optimal conditions for preparation of nanocomposite Taguchi experimental design method was used.

Research approach: Anti-corrosion properties of epoxy coating under the influence of very important factors such as the percentage of nano silica, anticorrosive pigment and pigment to resin ratio according to model L9 taguchi method was studied and analyzed. Anti-corrosion properties of epoxy coatings were studied by electrochemical impedance spectroscopy test (EIS) in 3/5% NaCl aqueous solution and salt fog test (salt spray). To investigate the distribution of nano silica particles in epoxy resin were analyzed by transmion electron microscope (TEM) and scanning electron microscope (SEM). The results show that using from zinc phosphate and nano-silica was able to improve the corrosion resistances.

Main results:Results shows that addition of zinc phosphate and nano silica to epoxy resin caused a decrease in number of blisters and corrosion products after exposure to corrosion test based on the results in Nyquist and Bode plots, also the similarity in results was observed for the epoxy coating loaded according to the optimum conditions with 8% zinc phosphate, 3% nano silica and pigment to resin ratio of one according to salt spary. The significance levels of the experimental parameters, which indicate how the factors affect the compressive addition of zinc phosphate and nano silica to epoxy resin, were determined by using variance (Anova) method.

Abstract Abstract
Research Subject: In recent years, the use of graphene nanoplatelets (GnPs) in polymer nanocomposites has attracted considerable attention. Dispersion state of GnPs in the polymer matrix has a great importance which can affect microstructure and final properties of nanocomposite. Therefore, in the present work, the effect of compatibilizer on the dispersion state of GnPs and also on internal structure, orientation, and tensile properties of polypropylene (PP)/GnPs nanocomposite fibers are investigated.
Research Approach: PP/GnPs nanocomposite fibers containing 0.1% and 0.5% GnPs with and without maleic anhydride-grafted polypropylene (PP-g-MA) were melt spun. Dispersion state and location of GnPs in the nanocomposite fibers were investigated by transmission electron microscopy (TEM) and small angle X-ray scattering (SAXS). Fiber orientation and crystallinity were studied by polarized Fourier transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC), respectively. Moreover, fracture behaviour of PP/GnPs nanocomposite fibers was investigated by cross-sectional scanning electron microscopy (SEM) images of tensile fractured samples. Using Halpin-Tsai model, experimental tensile moduli of fibers were compared with the predicted values.
Main Results: TEM images show that in the compatibilized PP/MA/GnPs nanocomposite fibers, GnPs aggregates decrease and their size also reduces, suggesting that GnPs dispersion improved. An increase in L_p of the compatibilized sample recorded from SAXS analysis indicates that the more GnPs are located in the intrafibrillar region. Based on polarized FTIR and DSC results, orientation and crystallinity of PP/G0.5 nanocomposite fiber are found to significantly increase after inclusion of PP-g-MA. Moreover, reinforcing effect of GnPs in PP/MA/GnPs nanocomposite fibers could be explained by better GnPs dispersion and changes in internal structure of fiber. Furthermore, the tensile fracture behavior of PP/GnPs nanocomposite fiber changes from ductile to brittle in the presence of PP-g-MA.

Abstract Abstract
Research subject: Nanocomposites are a new class of materials that have at least one of their major constituents, at least in one dimension, in the range of one to one hundred nanometers. Typically, nanocomposites have different and superior properties in terms of mechanical and physical properties than conventional composites.
Research approach: In this study, polyvinyl acetate was prepared by emulsion polymerization for polymer matrix. Then the diamond nanoparticles were modified with silane agent. Finally, polyvinyl acetate / diamond nanocomposite was prepared and analyzed with 0.5, 1, 1.5 and 2 wt% of modified diamond nanoparticles. To determine the properties and structure of the nanocomposite, FTIR, TGA, RMS, FESEM, oxygen permeation analysis was used in the films produced and contact angle measurements.
Main results: FTIR Analysis revealed that the modification of the diamond nanoparticles with the silane agent was well performed. FESEM images show that homogeneous nanocomposites were created. Oxygen permeability in polyvinyl acetate / diamond nanocomposite film decreases with increasing percentage of modified nanoparticles in nanocomposite. This is a valuable property if this nanocomposite is used as a fruit preservative coating. Contact angle measurement of polyvinyl acetate / diamond nanocomposite showed that by increasing the amount of modified diamond nanoparticles from 0.5 to 2 wt %, the hydrophobicity of nanocomposite film increased. Therefore, by increasing the specific amount of nanoparticles to the polymer matrix, the polymer properties such as heat resistance and tensile strength are increased which increases the efficiency of the polymer.

Abstract Research Subject: Poor mechanical strengths and lack of thermal stabilities of hydrogels confine their extensive practical applications in many areas. The growing scientific need for solving this problem and achievement to the hydrogels with improved properties has led to the design and production of the nanocomposite hydrogels.
Research Approach: The polymeric networks of nanocomposite hydrogels compared to the ordinary hydrogels have improved elasticity and rheological properties. Other points that increase the importance of structural studies of nanocomposite hydrogels are the high strength of these materials versus the application of external forces, as well as maintaining its structure against increasing of temperatures. In this regard, the type and amounts of nanomaterial, the preparation method and formation of hydrogel network have a significant role in improving the physical, chemical and biological properties of hydrogels, and, it must be noted that these parameters will depend on the application of nanocomposite hydrogels. This also highlights the need for the production of nanocomposite tailored hydrogels. Therefore, orientation of the range of nanomaterials, the preparation method and product identification, along with sufficient information on the application of these materials, might have an important role in ensuring the success of these materials, requiring comprehensive library research and studies on polymerization processes, morphology and rheology.
Main Results: In this review article, the scientific advances in the field of nanocomposite hydrogels, focusing on its types based on the type of nanoparticles, its properties, preparation methods, identification methods with a new perspective on rheology, thermal analysis and morphology is investigated. Finally, the applicability of these materials is collected in a comprehensive table in various fields such as tissue engineering, enhanced oil recovery, agriculture, and etc…

Abstract The aim of this project is the design and optimization of the formulation of epoxy adhesives for bonding metal to composite parts . This joints are most widely used in the aerospace industry to reduce stress concentration at a point. Joints for single edge joining include stainless steel metal with commercial code 316L and composite epoxy resin / carbon fiber. In this study, the effect of three types of additives: filler (alumina micro-particles), nylon 6.6 and phenolic resin (type of resin) on the mechanical and thermal properties of epoxy adhesive have been investigated. Tensile test results showed that increasing alumina fillers increases the tensile strength and overlap shear adhesive samples, respectively, in single lap joint dumbbells and elderly. The test showed that increasing the amount of nylon 6.6 When is slightly higher due to a sharp drop in tensile strength and overlap shear, respectively, in both cases is dog bone and single lap joint adhesives. This limit depends on the capacity epoxy ring to absorb amide hydrogens. The test for thermal properties (TGA) showed that increasing the amount of phenolic thermal stability is improved. High-temperature tensile test of appropriateness is also increasing impact of phenolic resin. Finally, the adhesive properties built with the similar adhesive (UHU) were compared. Results showed superiority in single lap joint metal to composite adhesive is made in the study.

Abstract In this study, phenolic compounds-coated ZnO@HAP nanocomposite (Ph.ZnO@HAP) was synthesized and used to improve the physical and chemical properties of chitosan hydrogel for biological application. At first, the phenolic compounds were extracted from walnut green hulls. The synthesis of Ph.ZnO@HAP nanocomposite was performed with the assistance of extracted phenols using a hydrothermal method. Chitosan hydrogel was also prepared using NaHCO₃ at 37°C. Hybrid hydrogels based on chitosan and Ph.ZnO@HAP nanocomposite were prepared in a similar way and then characterized by fourier-transform infrared spectroscopy (FTIR) and field emission scanning electron microscopy (FESEM). The antioxidant property, cytotoxicity, and osteogenesis of hybrid hydrogels were measured using DPPH radical scavenging method, MTT, and alkaline phosphatase enzyme assay, respectively. The FTIR spectra, FESEM images, EDX spectrum, and Zeta potential data showed that Ph.ZnO@HAP nanocomposites synthesized successfully with rod-like morphology, phenolic compounds coated on the surface and a negative particle surface charge. The results of DPPH experiment showed that the antioxidant property of the nanocomposite material increased in a concentration-dependent manner. The FESEM images of chitosan hybrid hydrogels with different concentrations of embedded Ph.ZnO@HAP nanocomposite showed that hybrid hydrogels have a more uniform porous structure, compared to the chitosan hydrogel. Moreover, by an increase in the nanocomposite concentration in the structure of hybrid hydrogels, the antioxidant property augmented. The results of the biological studies showed that the cytotoxicity of hybrid hydrogels on osteoblast-like cells (Saos-2) is lower than that of chitosan hydrogel. Also, hybrid hydrogels showed the higher potential in induction of osteogenesis than chitosan hydrogels.

Abstract Fiber production in nanoscale prepares high surface contact for fibers and leads to the improvement of their properties with respect to other fibers. A convenient and effective method for nanofiber production with different diameters is electrospinning. Various effective parameters on electrospinning processes, including environmental, equipment, and solution variables can produce fibers with different morphologies. PVA has been used in various fields of applied research because of its high thermal stability, biocompatibility, non-toxic and solubility in water. The published reports indicated that properties of the PVA are improved with the addition of bentonite. In this research, to prepare PVA/nano-bentonite nanofiber membrane, the optimum amounts of three effective variables on the above-mentioned processes were determined. According to the obtained results, the voltage of 11 kV, the feeding rate of 0.5 mL/h and bentonite concentration of 3% w/w were optimum conditions for the process of PVA/nano-bentonite nanofiber composite production. In this condition, the average diameter of produced nanofibers was 243 nm with the standard deviation of 0.0551 and the tensile strength of 7.64 MPa. The results showed that the addition of bentonite to PVA increase intensity of nanofibers and decrease the diameter of nanofibers from 308 nm to 243nm.Therfore, the produced PVA/bentonite nanofiber composite is a good membrane for water treatment.

Abstract In this study, three different size (100-300-500 µm) of the rubber powder (waste tire) were used in the formulation of epoxy- phenolic adhesive. Rubber powder was modified with grafting method by acrylamide monomer. In order to prevent any loss in properties such as modulus and strength of the adhesive, which is due to the addition of rubber powder to the adhesive, the micro particles of silica were used in formulation of epoxy- phenolic adhesive. The experiment was designed by Taguchi method, and in the experiment, the effect of the composition of rubber powder, size of rubber powder, composition of silica filler and phenolic resin on mechanical and thermal properties of epoxy adhesives were investigated. To study the mechanical properties of adhesives and adhesion properties, dumbbell-shaped specimens and single edge lap bonds that have been made of metal (stainless steel) to composite (epoxy resin / carbon fiber) were prepared and subjected to tensile test. Thermal stability and interfacial interaction between epoxy and filler in adhesive formulation were explored by thermogravimetric analysis and Fourier transform infrared spectroscopy analyses, respectively. Tensile test results showed that for lap- joint bonding with the addition of each factor in its optimal level into epoxy adhesive, strength, modulus and toughness increase by 7.5%, 27.56% and 114% respectively in comparison with the samples bonded with the neat epoxy adhesive. A significant increase was obtained in thermal stability for formulated adhesive samples compared with neat epoxy adhesive.