Pub Date : 2024-09-14DOI: 10.1177/09673911241273654
Yuesheng Yu, Bingnong Jiang, Yuan Chen, Lin Ye
Fused filament fabrication (FFF) is commonly utilised for 3D printing of semi-crystalline polymers, i.e., polypropylene (PP), while warpage deformation can often be observed in the printed products, with significantly reduced surface quality and mechanical properties. This study develops computational models for predicting rectangular boxes made of PP with different thicknesses under the FFF process to study the stress concentration and warpage mechanisms during 3D printing. Numerical models were established based on heat transfer, thermoelasticity, and crystallisation kinetics, with an activating elemental approach to calculate the FFF process of PP. The numerical models were validated with repetitive printing tests to study the mechanisms and relationships of stress conditions and warpage formation in PP boxes under FFF. The results show that the boxes with the thinnest thickness exhibited mostly severe warpage deformation (6.8 mm/5.9 mm in experiment and simulation, respectively), which is much more than that of the thickest box (1.3 mm/1.6 mm in experiment and simulation, respectively). The average crystallinity of the three boxes increases as the box thickness increases, but to a lesser extent. In terms of residual stress, the thinner box has a smaller residual stress (25.1 MPa, almost 45% of the thicker box).
{"title":"Modelling and characterising FFF process of semi-crystalline polymers: Warpage formation and mechanism analysis","authors":"Yuesheng Yu, Bingnong Jiang, Yuan Chen, Lin Ye","doi":"10.1177/09673911241273654","DOIUrl":"https://doi.org/10.1177/09673911241273654","url":null,"abstract":"Fused filament fabrication (FFF) is commonly utilised for 3D printing of semi-crystalline polymers, i.e., polypropylene (PP), while warpage deformation can often be observed in the printed products, with significantly reduced surface quality and mechanical properties. This study develops computational models for predicting rectangular boxes made of PP with different thicknesses under the FFF process to study the stress concentration and warpage mechanisms during 3D printing. Numerical models were established based on heat transfer, thermoelasticity, and crystallisation kinetics, with an activating elemental approach to calculate the FFF process of PP. The numerical models were validated with repetitive printing tests to study the mechanisms and relationships of stress conditions and warpage formation in PP boxes under FFF. The results show that the boxes with the thinnest thickness exhibited mostly severe warpage deformation (6.8 mm/5.9 mm in experiment and simulation, respectively), which is much more than that of the thickest box (1.3 mm/1.6 mm in experiment and simulation, respectively). The average crystallinity of the three boxes increases as the box thickness increases, but to a lesser extent. In terms of residual stress, the thinner box has a smaller residual stress (25.1 MPa, almost 45% of the thicker box).","PeriodicalId":20417,"journal":{"name":"Polymers and Polymer Composites","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142257366","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-10DOI: 10.1177/09673911241282424
Muhammad Asif Javed, Abuzar Ghaffari, H M Atif, Ahmed S Sowayan, Sami Ullah Khan
The underlying investigation reports the effects of the magnetohydrodynamics (MHD) and non-linear slip coefficients on the coating thickness of the web/substrate during the blade coating process. Two dimensional analysis of the blade coating process is performed using non-Newtonian nanofluid model with the help of basic equations of fluid dynamics are performed. Firstly, the system of equations of motion (EOM) is transformed into the non-dimensional form by using the scaling factors. Secondly, the modeled equations are further simplified with the help of lubrication approximation theory (LAT). The resulting boundary value problem is transformed into stream function to eliminate the pressure gradient from the flow equation and then numerically tackled with the Matlab built-in function bvp4c with the method of false position (Regula-Falsi Method). A comparative study of numerical data with results simulated by artificial neural networks (ANN) found that results are in excellent agreement. The impact of sundry parameters on physical quantities is examined through graphical representation. Results indicate that the influence of magnetohydrodynamics (MHD), nanoparticle and slip effects cannot be ignored during the blade coating flow, as a significant impact of these parameters is observed on velocity, temperature, pressure, coating thickness, blade load, and streamlines.
{"title":"Machine learning non-isothermal study of the blade coating process (NIS-BCP) using non-Newtonian nanofluid with magnetohydrodynamic (MHD) and slip effects","authors":"Muhammad Asif Javed, Abuzar Ghaffari, H M Atif, Ahmed S Sowayan, Sami Ullah Khan","doi":"10.1177/09673911241282424","DOIUrl":"https://doi.org/10.1177/09673911241282424","url":null,"abstract":"The underlying investigation reports the effects of the magnetohydrodynamics (MHD) and non-linear slip coefficients on the coating thickness of the web/substrate during the blade coating process. Two dimensional analysis of the blade coating process is performed using non-Newtonian nanofluid model with the help of basic equations of fluid dynamics are performed. Firstly, the system of equations of motion (EOM) is transformed into the non-dimensional form by using the scaling factors. Secondly, the modeled equations are further simplified with the help of lubrication approximation theory (LAT). The resulting boundary value problem is transformed into stream function to eliminate the pressure gradient from the flow equation and then numerically tackled with the Matlab built-in function bvp4c with the method of false position (Regula-Falsi Method). A comparative study of numerical data with results simulated by artificial neural networks (ANN) found that results are in excellent agreement. The impact of sundry parameters on physical quantities is examined through graphical representation. Results indicate that the influence of magnetohydrodynamics (MHD), nanoparticle and slip effects cannot be ignored during the blade coating flow, as a significant impact of these parameters is observed on velocity, temperature, pressure, coating thickness, blade load, and streamlines.","PeriodicalId":20417,"journal":{"name":"Polymers and Polymer Composites","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142208035","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-29DOI: 10.1177/09673911241274092
Feras Zweiri, Neil A. Williams, Homayoun Hadavinia
Polyurethane elastomers (PU) are used in various applications, such as wind turbine blades, to safeguard structural integrity, maintain shape, and enhance survivability under repeated impact loading from rain droplets and sand particles. This study investigates the impact of individual and combination of additive carbon nanotubes, graphene, and fumed nanosilica nanomaterials, totalling 0.3 wt% loading to PU, on water uptake capacity and any adverse effect on mechanical properties after exposure to saturation. Alongside the control pure PU, five types of PUs with varying additive nanomaterial types and contents are examined. Experimental measurements of the temperature-dependent moisture absorption, diffusion coefficients and permeabilities for the pure PU and its nanocomposites are conducted at 22°C, 32°C, and 45°C. In addition, uniaxial tensile tests were conducted on both dry and water-saturated coatings, and their mechanical properties were compared. Physicochemical characterisation of the coating materials is performed using the Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and dynamic mechanical analysis (DMA) techniques. Water contact angle (WCA) and surface free energy measured. Morphological features of fracture surfaces are studied by scanning electron microscopy (SEM) and optical microscopy.
{"title":"Performance of polyurethane and polyurethane nanocomposites modified by graphene, carbon nanotubes, and fumed silica in dry and wet environments","authors":"Feras Zweiri, Neil A. Williams, Homayoun Hadavinia","doi":"10.1177/09673911241274092","DOIUrl":"https://doi.org/10.1177/09673911241274092","url":null,"abstract":"Polyurethane elastomers (PU) are used in various applications, such as wind turbine blades, to safeguard structural integrity, maintain shape, and enhance survivability under repeated impact loading from rain droplets and sand particles. This study investigates the impact of individual and combination of additive carbon nanotubes, graphene, and fumed nanosilica nanomaterials, totalling 0.3 wt% loading to PU, on water uptake capacity and any adverse effect on mechanical properties after exposure to saturation. Alongside the control pure PU, five types of PUs with varying additive nanomaterial types and contents are examined. Experimental measurements of the temperature-dependent moisture absorption, diffusion coefficients and permeabilities for the pure PU and its nanocomposites are conducted at 22°C, 32°C, and 45°C. In addition, uniaxial tensile tests were conducted on both dry and water-saturated coatings, and their mechanical properties were compared. Physicochemical characterisation of the coating materials is performed using the Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and dynamic mechanical analysis (DMA) techniques. Water contact angle (WCA) and surface free energy measured. Morphological features of fracture surfaces are studied by scanning electron microscopy (SEM) and optical microscopy.","PeriodicalId":20417,"journal":{"name":"Polymers and Polymer Composites","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142208038","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-28DOI: 10.1177/09673911241275806
Muhammad Mubeen Safdar, Muhammad Imran Khan, Maha Alsunbul, Eman Fayad, Zulfiqar Ahmad Rehan, Tehseen Ullah, HM Fayzan Shakir, Muhammad Umair
Generally, 2D woven structures are used in a different high performance applications. But 2D woven natural fibers based structures have poor mechanical properties as compared to glass and other synthetic yarns. One of the possible solutions to overcome this problem is to develop 3D woven structures with natural fibers. The present work developed hemp yarn based three types of novel 3D woven structures, i.e., hybrid through the thickness (HB-1 (TT)), novel woven layer to layer structure (HB-2 (LL)), and layer to layer structure with double warp yarn (HB-3 (LL)). Furthermore to evaluate the impact of interlocking pattern on the static mechanical properties i.e., tensile, tear, puncture resistance and stiffness tests of the strucures were performed. The findings reveal variations in tensile strength among different 3D woven structures. Specifically, the 3D woven HB-3 (LL) configuration demonstrated the highest tensile strength, whereas the HB-1 (TT) structure exhibited the lowest. In the warp orientation, the tensile strength of the 3D woven HB-3 (LL) structure surpassed that of the HB-1 (TT) structure by 25.75%. Additionally, the stiffness results for the 3D woven HB-1 (TT) structure in the warp direction exceeded those of the HB-2 (LL) structure by 55.53%. Moreover, the HB-3 (LL) structure displayed superior puncture resistance compared to other 3D woven configurations. Furthermore, in the warp direction, the tear strength of the 3D woven HB-1 (TT) structure exceeded that of the HB-2 (LL) structure by 16.40%. Statistical analysis utilizing one-way ANOVA (Tukey) revealed that the influence of 3D woven hybrid structures on the outcomes of mechanical testing was statistically significant.
{"title":"Effect of hybrid weaving patterns on mechanical performance of 3D woven structures","authors":"Muhammad Mubeen Safdar, Muhammad Imran Khan, Maha Alsunbul, Eman Fayad, Zulfiqar Ahmad Rehan, Tehseen Ullah, HM Fayzan Shakir, Muhammad Umair","doi":"10.1177/09673911241275806","DOIUrl":"https://doi.org/10.1177/09673911241275806","url":null,"abstract":"Generally, 2D woven structures are used in a different high performance applications. But 2D woven natural fibers based structures have poor mechanical properties as compared to glass and other synthetic yarns. One of the possible solutions to overcome this problem is to develop 3D woven structures with natural fibers. The present work developed hemp yarn based three types of novel 3D woven structures, i.e., hybrid through the thickness (HB-1 (TT)), novel woven layer to layer structure (HB-2 (LL)), and layer to layer structure with double warp yarn (HB-3 (LL)). Furthermore to evaluate the impact of interlocking pattern on the static mechanical properties i.e., tensile, tear, puncture resistance and stiffness tests of the strucures were performed. The findings reveal variations in tensile strength among different 3D woven structures. Specifically, the 3D woven HB-3 (LL) configuration demonstrated the highest tensile strength, whereas the HB-1 (TT) structure exhibited the lowest. In the warp orientation, the tensile strength of the 3D woven HB-3 (LL) structure surpassed that of the HB-1 (TT) structure by 25.75%. Additionally, the stiffness results for the 3D woven HB-1 (TT) structure in the warp direction exceeded those of the HB-2 (LL) structure by 55.53%. Moreover, the HB-3 (LL) structure displayed superior puncture resistance compared to other 3D woven configurations. Furthermore, in the warp direction, the tear strength of the 3D woven HB-1 (TT) structure exceeded that of the HB-2 (LL) structure by 16.40%. Statistical analysis utilizing one-way ANOVA (Tukey) revealed that the influence of 3D woven hybrid structures on the outcomes of mechanical testing was statistically significant.","PeriodicalId":20417,"journal":{"name":"Polymers and Polymer Composites","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142208036","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-23DOI: 10.1177/09673911241279770
Hicham El Hatka, Youssef Hafidi, Najim Ittobane
This study investigated the potential of bis(2-hydroxyethyl) terephthalate (BHET), derived from the glycolysis of polyethylene terephthalate (PET) waste, as an additive in the synthesis of flexible polyurethane foam (FPUF), addressing the escalating environmental concerns associated with PET waste accumulation and the demand for sustainable material solutions. The influence of varying BHET content on the synthesis process, cellular architecture, and the intricate interplay between compositional variations and the resultant physical, mechanical, and thermal properties of FPUFs has been investigated. Our examination approach included analyses of foam density and cell morphology, comprehensive Fourier transform infrared (FTIR) spectroscopy for chemical structure elucidation, thermogravimetric analysis (TGA) to assess thermal stability, and differential scanning calorimetry (DSC) alongside mechanical property evaluations to discern the impact of BHET on foam performance metrics. Results emphasized the pivotal role of BHET in refining foam characteristics, where its inclusion facilitated the formation of foams with improvement in cell uniformity, subsequently affecting the foam’s apparent density. FTIR spectra analysis provided insight into the hydrogen bonding dynamics within polyurethane segments, revealing how BHET integration influenced microphase separation and the structural coherence of the material. The thermal and mechanical property assessments through TGA and mechanical testing demonstrated that the addition of BHET substantially augmented the thermal stability and mechanical performance of FPUFs.
{"title":"Investigation of effects of bis(2-hydroxyethyl) terephthalate derived from glycolysis of polyethylene terephthalate on the properties of flexible polyurethane foam","authors":"Hicham El Hatka, Youssef Hafidi, Najim Ittobane","doi":"10.1177/09673911241279770","DOIUrl":"https://doi.org/10.1177/09673911241279770","url":null,"abstract":"This study investigated the potential of bis(2-hydroxyethyl) terephthalate (BHET), derived from the glycolysis of polyethylene terephthalate (PET) waste, as an additive in the synthesis of flexible polyurethane foam (FPUF), addressing the escalating environmental concerns associated with PET waste accumulation and the demand for sustainable material solutions. The influence of varying BHET content on the synthesis process, cellular architecture, and the intricate interplay between compositional variations and the resultant physical, mechanical, and thermal properties of FPUFs has been investigated. Our examination approach included analyses of foam density and cell morphology, comprehensive Fourier transform infrared (FTIR) spectroscopy for chemical structure elucidation, thermogravimetric analysis (TGA) to assess thermal stability, and differential scanning calorimetry (DSC) alongside mechanical property evaluations to discern the impact of BHET on foam performance metrics. Results emphasized the pivotal role of BHET in refining foam characteristics, where its inclusion facilitated the formation of foams with improvement in cell uniformity, subsequently affecting the foam’s apparent density. FTIR spectra analysis provided insight into the hydrogen bonding dynamics within polyurethane segments, revealing how BHET integration influenced microphase separation and the structural coherence of the material. The thermal and mechanical property assessments through TGA and mechanical testing demonstrated that the addition of BHET substantially augmented the thermal stability and mechanical performance of FPUFs.","PeriodicalId":20417,"journal":{"name":"Polymers and Polymer Composites","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142208037","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-13DOI: 10.1177/09673911241273679
Z Abbas, M Javed, A Hanif, MY Rafiq, S Khaliq
Blade coating is a widely used technique for achieving smooth surfaces by applying a protective fluid layer from the blade onto the moving substrate. Under the blade coating phenomena, the impacts of MHD, velocity slip, and heat distribution of the third-grade fluid for both planar and exponential coaters are taken into discussion. Lubrication approximation theory is employed for solving nonlinear equations, while the numerical method known as the shooting technique is utilized to characterize pressure, pressure gradient, velocity, and heat distribution. Numerous parameters including the slip parameter, third-grade fluid, coating thickness, and MHD are numerically investigated to show the effect on fluid flow and shown in several graphs and tables. The results prove the viscoelastic nature of fluid along with MHD and viscous slip to be controlling parameters of pressure and blade load which lead to varying coating thickness, which may help in achieving improved substrate life and efficient coating process.
{"title":"Rheology of magnetohydrodynamic viscoelastic fluid flow and heat transfer during the blade coating process with blade slip","authors":"Z Abbas, M Javed, A Hanif, MY Rafiq, S Khaliq","doi":"10.1177/09673911241273679","DOIUrl":"https://doi.org/10.1177/09673911241273679","url":null,"abstract":"Blade coating is a widely used technique for achieving smooth surfaces by applying a protective fluid layer from the blade onto the moving substrate. Under the blade coating phenomena, the impacts of MHD, velocity slip, and heat distribution of the third-grade fluid for both planar and exponential coaters are taken into discussion. Lubrication approximation theory is employed for solving nonlinear equations, while the numerical method known as the shooting technique is utilized to characterize pressure, pressure gradient, velocity, and heat distribution. Numerous parameters including the slip parameter, third-grade fluid, coating thickness, and MHD are numerically investigated to show the effect on fluid flow and shown in several graphs and tables. The results prove the viscoelastic nature of fluid along with MHD and viscous slip to be controlling parameters of pressure and blade load which lead to varying coating thickness, which may help in achieving improved substrate life and efficient coating process.","PeriodicalId":20417,"journal":{"name":"Polymers and Polymer Composites","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142208040","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-12DOI: 10.1177/09673911241275302
Md. Anwarul Karim, Sharmin Sultana Dipti, Mohammad Mahfuz Enam Elahi
Polyvinyl alcohol has the potential to be used in fuel cell membranes due to its chemical, mechanical, and membrane-forming capabilities, as well as its higher hydrophilicity and low methanol permeability. However, the pure PVA membrane has a lower proton conductivity than the NafionTM membrane. With the addition of some ceramic fillers, PVA can be a possible alternative to NafionTM membranes. Therefore, we used the solution method to prepare three polyvinyl alcohol-based composite membranes with the following compositions: a) 5 wt% PVA (polyvinyl alcohol), b) 5 wt% PVA/2 wt % PEG (polyethylene glycol)/wt.1% silicon dioxide (SiO2) nanoparticles, and c) 5 wt% PVA/2 wt% PEG/wt.1% clay powder. The membranes were characterized using Fourier Transform Infrared Spectroscopy (FTIR), Thermal Gravimetric Analysis (TGA), Scanning Electron Microscopy (SEM), Energy dispersive X-ray (EDX), oxidative stability, ion exchange capacity, water absorption characteristics, conductivity, and permeability. FITR, EDX, and SEM confirmed the successful fabrication of the composite membrane, while TGA demonstrated membrane thermal stability and other parameters relevant to fuel cell membranes. The methanol permeability of the membrane is pure 5 wt % PVA, 5 wt%PVA/2 wt%/1 wt% SiO2, and 5 wt% PVA/2 wt% PEG/wt.1% Clay measured 2.37 × 10−6 cm2/s, 2.89 × 10−6 cm2/s, and 1.57 × 10−6 cm2/s, respectively. The methanol permeability of 5 wt% PVA/2 wt% PEG/wt.1% Clay is better than of Nafion117 (5.16 × 10−6 cm2/s as reported). The membrane 5 wt% PVA/2 wt% PEG/1% Clay exhibits satisfactory levels of oxidative stability (RW% = 94.09 at 1.32 h), IEC (0.232 meq/g), conductivity (0.00432 S/cm), methanol permeability (1.57 × 10−6 cm2/s), selectivity (3.63 × 10−4 Ss/cm3), and better water uptake properties at fuel cell operating temperature. As a result, it is reasonable to expect that PVA-based modified membranes will outperform NafionTM membranes in the future.
{"title":"Clay powder in polymer composite membranes enhanced the performance of direct methanol fuel cells","authors":"Md. Anwarul Karim, Sharmin Sultana Dipti, Mohammad Mahfuz Enam Elahi","doi":"10.1177/09673911241275302","DOIUrl":"https://doi.org/10.1177/09673911241275302","url":null,"abstract":"Polyvinyl alcohol has the potential to be used in fuel cell membranes due to its chemical, mechanical, and membrane-forming capabilities, as well as its higher hydrophilicity and low methanol permeability. However, the pure PVA membrane has a lower proton conductivity than the Nafion<jats:sup>TM</jats:sup> membrane. With the addition of some ceramic fillers, PVA can be a possible alternative to Nafion<jats:sup>TM</jats:sup> membranes. Therefore, we used the solution method to prepare three polyvinyl alcohol-based composite membranes with the following compositions: a) 5 wt% PVA (polyvinyl alcohol), b) 5 wt% PVA/2 wt % PEG (polyethylene glycol)/wt.1% silicon dioxide (SiO<jats:sub>2</jats:sub>) nanoparticles, and c) 5 wt% PVA/2 wt% PEG/wt.1% clay powder. The membranes were characterized using Fourier Transform Infrared Spectroscopy (FTIR), Thermal Gravimetric Analysis (TGA), Scanning Electron Microscopy (SEM), Energy dispersive X-ray (EDX), oxidative stability, ion exchange capacity, water absorption characteristics, conductivity, and permeability. FITR, EDX, and SEM confirmed the successful fabrication of the composite membrane, while TGA demonstrated membrane thermal stability and other parameters relevant to fuel cell membranes. The methanol permeability of the membrane is pure 5 wt % PVA, 5 wt%PVA/2 wt%/1 wt% SiO<jats:sub>2</jats:sub>, and 5 wt% PVA/2 wt% PEG/wt.1% Clay measured 2.37 × 10<jats:sup>−6</jats:sup> cm<jats:sup>2</jats:sup>/s, 2.89 × 10<jats:sup>−6</jats:sup> cm<jats:sup>2</jats:sup>/s, and 1.57 × 10<jats:sup>−6</jats:sup> cm<jats:sup>2</jats:sup>/s, respectively. The methanol permeability of 5 wt% PVA/2 wt% PEG/wt.1% Clay is better than of Nafion117 (5.16 × 10<jats:sup>−6</jats:sup> cm<jats:sup>2</jats:sup>/s as reported). The membrane 5 wt% PVA/2 wt% PEG/1% Clay exhibits satisfactory levels of oxidative stability (RW% = 94.09 at 1.32 h), IEC (0.232 meq/g), conductivity (0.00432 S/cm), methanol permeability (1.57 × 10<jats:sup>−6</jats:sup> cm<jats:sup>2</jats:sup>/s), selectivity (3.63 × 10<jats:sup>−4</jats:sup> Ss/cm<jats:sup>3</jats:sup>), and better water uptake properties at fuel cell operating temperature. As a result, it is reasonable to expect that PVA-based modified membranes will outperform Nafion<jats:sup>TM</jats:sup> membranes in the future.","PeriodicalId":20417,"journal":{"name":"Polymers and Polymer Composites","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142208039","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-10DOI: 10.1177/09673911241275586
Hikmet Yazıcı
This study aimed to prepare and characterize PAA/carbonized waste rubber composites. Composites containing different proportions of PAA, and carbonized waste rubber were prepared (0.5%, 1% and 2% carbonized waste rubber by weight of PAA). Structural characterization of the prepared composites was carried out using FT-IR and XRD techniques. Thermal stability was examined with the TGA/DTG technique. Their morphologies were investigated using SEM. It is evaluated that the thermal stability of PAA is increased by preparing the composites obtained from all the results and the obtained composites can be used in areas where the thermal management of the electronic product is required.
{"title":"Preparation and characterization of Poly(acrylic acid)/carbonized waste rubber composites","authors":"Hikmet Yazıcı","doi":"10.1177/09673911241275586","DOIUrl":"https://doi.org/10.1177/09673911241275586","url":null,"abstract":"This study aimed to prepare and characterize PAA/carbonized waste rubber composites. Composites containing different proportions of PAA, and carbonized waste rubber were prepared (0.5%, 1% and 2% carbonized waste rubber by weight of PAA). Structural characterization of the prepared composites was carried out using FT-IR and XRD techniques. Thermal stability was examined with the TGA/DTG technique. Their morphologies were investigated using SEM. It is evaluated that the thermal stability of PAA is increased by preparing the composites obtained from all the results and the obtained composites can be used in areas where the thermal management of the electronic product is required.","PeriodicalId":20417,"journal":{"name":"Polymers and Polymer Composites","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141936506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-06DOI: 10.1177/09673911241273578
Waham Ashaier Laftah, Wan Aizan Wan Abdul Rahman
The sizing of pineapple leaf fiber (PALF) using cornstarch, polyvinyl acetate (PVA), and carboxymethyl cellulose (CMC) was analyzed, incorporating glycerol and urea as a plasticizer and stabilizer, respectively. The impact of various sizing agents on the physical properties of PALF was evaluated. A comparison between treated and untreated PALF was conducted using FTIR, thermogravimetric analysis (TGA), and tenacity testing. The thermal stability of PALF improved with PVA treatment, showing decomposition temperatures of 363.831°C after modification compared to 343.163°C before modification. Conversely, CMC and cornstarch did not affect PALF's thermal stability. The tenacity test revealed that untreated PALF had the highest breaking force, while the elongation at break increased after sizing. The drying rate of PALF decreased post-sizing, whereas water absorption increased with CMC, PVA, and cornstarch treatments. Overall, sizing agents enhanced the handling and physical properties of PALF, indicating its potential as an alternative material source for textile applications.
{"title":"Chemical surface modification of pineapple leaf fiber for polymer composites applications: Comparative study","authors":"Waham Ashaier Laftah, Wan Aizan Wan Abdul Rahman","doi":"10.1177/09673911241273578","DOIUrl":"https://doi.org/10.1177/09673911241273578","url":null,"abstract":"The sizing of pineapple leaf fiber (PALF) using cornstarch, polyvinyl acetate (PVA), and carboxymethyl cellulose (CMC) was analyzed, incorporating glycerol and urea as a plasticizer and stabilizer, respectively. The impact of various sizing agents on the physical properties of PALF was evaluated. A comparison between treated and untreated PALF was conducted using FTIR, thermogravimetric analysis (TGA), and tenacity testing. The thermal stability of PALF improved with PVA treatment, showing decomposition temperatures of 363.831°C after modification compared to 343.163°C before modification. Conversely, CMC and cornstarch did not affect PALF's thermal stability. The tenacity test revealed that untreated PALF had the highest breaking force, while the elongation at break increased after sizing. The drying rate of PALF decreased post-sizing, whereas water absorption increased with CMC, PVA, and cornstarch treatments. Overall, sizing agents enhanced the handling and physical properties of PALF, indicating its potential as an alternative material source for textile applications.","PeriodicalId":20417,"journal":{"name":"Polymers and Polymer Composites","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141936507","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-25DOI: 10.1177/09673911241245006
Qing Ma, Xiaotong Fang, Yerong Shi, Jing Hu
UV-cured 3D printing technology had become more and more popular due to its rapid printing speed and high molding accuracy. However, for ordinary Direct-ink-writing (DIW) printers, though there were widely materials can be used, but they cannot be quickly printed and molding accuracy was much low. Therefore, a simple method combined UV-cured and DIW was summarized in this paper, before DIW the mixed slurry (FeSiB and Epoxy resins soft magnetic composites without photoinitiator added) was pre-curing by UV for some time to a semi-cured state, the rheological properties of the slurry were investigated and the magnetic, mechanical properties and micromorphology of printed products were studied. Compared with the printed products without UV pre-curing, the coercive force (Hc) was reduced by 20.36%, the elastic modulus increased by 34.41%, and the insulating coating after UV pre-curing was more uniform, with no obvious defects.
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