Polymer electrolyte membranes (PEMs) play a vital role in electrochemical devices, facilitating ion conduction while blocking gases and electrons. Their effectiveness is closely linked to their microstructural properties, especially the free volume, which impacts ionic conductivity, mechanical strength, and overall device performance. This study examines the behavior of PVC/PMMA/SSA blends under electric fields, using Positron Annihilation Lifetime Spectroscopy (PALS) to assess free volume and dielectric properties. The study involved preparing and characterizing membranes through x‐ray diffraction (XRD), thermogravimetric analysis (TGA), and PALS. XRD results indicated semi‐crystalline structures with changes in intensity due to temperature variations, while TGA highlighted changes in thermal stability under different electric fields. PALS measurements showed that free volume varied with temperature and electric field strength, influencing the material's dielectric and mechanical characteristics. The results revealed that higher electric fields reduced free volume while enhancing dielectric properties. The dielectric constant and loss were found to depend on frequency, which was affected by the polar SO3H groups. Impedance spectroscopy provided further insights into the electrical properties, showing increased dc conductivity with stronger electric fields. A correlation between the free volume investigated from PAL and the electrical properties was observed. This study emphasizes the significance of free volume and external electric field in optimizing PEMs for advanced energy applications.
聚合物电解质膜（PEM）在电化学设备中发挥着至关重要的作用，在促进离子传导的同时阻挡气体和电子。其有效性与其微结构特性密切相关，尤其是自由体积，自由体积会影响离子传导性、机械强度和整体设备性能。本研究利用正电子湮没寿命谱 (PALS) 评估自由体积和介电特性，研究 PVC/PMMA/SSA 混合物在电场下的行为。研究包括通过 X 射线衍射 (XRD)、热重分析 (TGA) 和正电子湮没寿命谱 (PALS) 制备和表征膜。X 射线衍射结果表明，半晶体结构的强度随温度变化而变化，而热重分析则强调了不同电场下热稳定性的变化。PALS 测量结果表明，自由体积随温度和电场强度的变化而变化，从而影响了材料的介电和机械特性。结果表明，电场越强，自由体积越小，介电特性越强。介电常数和损耗取决于频率，而频率又受到极性 SO3H 基团的影响。阻抗光谱进一步揭示了电学特性，表明随着电场的增强，直流电导率也会增加。通过 PAL 研究出的自由体积与电学特性之间存在相关性。这项研究强调了自由体积和外部电场在优化先进能源应用的 PEM 中的重要性。
{"title":"Effect of the electric field on the free volume investigated from positron annihilation lifetime and dielectric properties of sulfonated PVC/PMMA","authors":"M. R. M. Elsharkawy, Wael M. Mohammed","doi":"10.1002/pat.6519","DOIUrl":"https://doi.org/10.1002/pat.6519","url":null,"abstract":"Polymer electrolyte membranes (PEMs) play a vital role in electrochemical devices, facilitating ion conduction while blocking gases and electrons. Their effectiveness is closely linked to their microstructural properties, especially the free volume, which impacts ionic conductivity, mechanical strength, and overall device performance. This study examines the behavior of PVC/PMMA/SSA blends under electric fields, using Positron Annihilation Lifetime Spectroscopy (PALS) to assess free volume and dielectric properties. The study involved preparing and characterizing membranes through x‐ray diffraction (XRD), thermogravimetric analysis (TGA), and PALS. XRD results indicated semi‐crystalline structures with changes in intensity due to temperature variations, while TGA highlighted changes in thermal stability under different electric fields. PALS measurements showed that free volume varied with temperature and electric field strength, influencing the material's dielectric and mechanical characteristics. The results revealed that higher electric fields reduced free volume while enhancing dielectric properties. The dielectric constant and loss were found to depend on frequency, which was affected by the polar SO3H groups. Impedance spectroscopy provided further insights into the electrical properties, showing increased dc conductivity with stronger electric fields. A correlation between the free volume investigated from PAL and the electrical properties was observed. This study emphasizes the significance of free volume and external electric field in optimizing PEMs for advanced energy applications.","PeriodicalId":20382,"journal":{"name":"Polymers for Advanced Technologies","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141697694","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Electrospraying has emerged as a versatile technique in the pharmaceutical field due to its potential in drug delivery and formulation. With its advantages of cost‐effectiveness, reproducibility, ease of operation, and scalability, electrospraying offers numerous benefits for pharmaceutical applications. Notably, the production of nanoparticles using electrospraying provides unique properties, including small size, drug encapsulation capabilities, biocompatibility, and scalability. Electrospray nanoparticles have demonstrated significant promise in various drug delivery routes, such as oral and topical administration. These nanoparticles enhance drug stability, protection, and permeability, effectively overcoming limitations associated with these routes. Moreover, electrospray nanoparticles have proven valuable in targeted drug delivery, improving drug bioavailability and efficacy. Their ability to penetrate tissues and cells enables enhanced drug delivery to specific sites within the body. Additionally, electrospray nanoparticles can be tailored with targeting ligands or responsive components for controlled release and combination therapy, exhibiting successful applications in cancer treatment and neurological disorders. Therefore, electrospray nanoparticle technology shows great promise in biomedical applications, offering a versatile platform for targeted drug delivery and therapeutic interventions. This comprehensive review examines the various drug delivery applications of electrospraying and provides insights into its possibilities and challenges. The paper discusses the principles, methods, and parameters of electrospraying, while also exploring its use in fabricating drug delivery systems, addressing poorly soluble drugs. By synthesizing the findings from multiple studies, this review offers a comprehensive understanding of electrospraying's current state and potential in the pharmaceutical industry.
{"title":"Review on electrospray nanoparticles for drug delivery: Exploring applications","authors":"Pratikshkumar R. Patel, Dieter Haemmerich","doi":"10.1002/pat.6507","DOIUrl":"https://doi.org/10.1002/pat.6507","url":null,"abstract":"Electrospraying has emerged as a versatile technique in the pharmaceutical field due to its potential in drug delivery and formulation. With its advantages of cost‐effectiveness, reproducibility, ease of operation, and scalability, electrospraying offers numerous benefits for pharmaceutical applications. Notably, the production of nanoparticles using electrospraying provides unique properties, including small size, drug encapsulation capabilities, biocompatibility, and scalability. Electrospray nanoparticles have demonstrated significant promise in various drug delivery routes, such as oral and topical administration. These nanoparticles enhance drug stability, protection, and permeability, effectively overcoming limitations associated with these routes. Moreover, electrospray nanoparticles have proven valuable in targeted drug delivery, improving drug bioavailability and efficacy. Their ability to penetrate tissues and cells enables enhanced drug delivery to specific sites within the body. Additionally, electrospray nanoparticles can be tailored with targeting ligands or responsive components for controlled release and combination therapy, exhibiting successful applications in cancer treatment and neurological disorders. Therefore, electrospray nanoparticle technology shows great promise in biomedical applications, offering a versatile platform for targeted drug delivery and therapeutic interventions. This comprehensive review examines the various drug delivery applications of electrospraying and provides insights into its possibilities and challenges. The paper discusses the principles, methods, and parameters of electrospraying, while also exploring its use in fabricating drug delivery systems, addressing poorly soluble drugs. By synthesizing the findings from multiple studies, this review offers a comprehensive understanding of electrospraying's current state and potential in the pharmaceutical industry.","PeriodicalId":20382,"journal":{"name":"Polymers for Advanced Technologies","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141709991","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Centella asiatica phytocompounds coated onto Multi‐Walled Carbon Nanotube (MWCNT) possessing antibacterial activity were prepared using a simple physical absorption method. The incorporation of Centella asiatica phytocompounds into functionalized MWCNTs could improve the physical properties of Centella asiatica phytocompounds conjugated MWCNT compared to pure MWCNT. Fourier Transform Infrared Spectroscopy (FTIR) results depict the presence of bioactive compounds on MWCNT coatings and the Raman spectrum confirms the presence of carbon in various ranges by their peaks from 636 to 1594.46 cm−1 in the MWCNT. Scanning Electron Microscope (SEM) micrograph images confirmed the existence of MWCNT‐Nano composites with Centella asiatica phytocompounds exhibiting the surface structure with pore clarity and visible pipes. Transmission Electron Microscope (TEM) images show the uniform dispersed spherical ultrathin nanosheets at the size of 10–20 nm. Further anti‐bacterial analysis results revealed that Centella asiatica phytocompounds coating enhances the anti‐bacterial activity of MWCNT. Prepared Centella asiatica phytocompounds ‐MWCNT possess maximal inhibition and produces high zones of inhibition 11 ± 0.06, 17 ± 0.08, 14 ± 0.07, and 16 ± 0.08 mm against four food‐spoiling bacterial clinical pathogens Salmonella typhi, Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumonia respectively. Centella asiatica phytocompounds conjugated‐MWCNT spin‐coated packaging showed good preservation properties. Centella asiatica phytocompounds conjugated with MWCNTs provide antimicrobial properties, enabling the development of novel food packaging materials that can protect food from spoilage, increase food stability, and sustainability, and improve the shelf life of food.
{"title":"Multi‐walled carbon nanotubes doped with Phytocompounds of Centella asiatica for food packing applications and their anti‐microbial properties","authors":"Santhini Sivakumar, T. A. Hema","doi":"10.1002/pat.6518","DOIUrl":"https://doi.org/10.1002/pat.6518","url":null,"abstract":"Centella asiatica phytocompounds coated onto Multi‐Walled Carbon Nanotube (MWCNT) possessing antibacterial activity were prepared using a simple physical absorption method. The incorporation of Centella asiatica phytocompounds into functionalized MWCNTs could improve the physical properties of Centella asiatica phytocompounds conjugated MWCNT compared to pure MWCNT. Fourier Transform Infrared Spectroscopy (FTIR) results depict the presence of bioactive compounds on MWCNT coatings and the Raman spectrum confirms the presence of carbon in various ranges by their peaks from 636 to 1594.46 cm−1 in the MWCNT. Scanning Electron Microscope (SEM) micrograph images confirmed the existence of MWCNT‐Nano composites with Centella asiatica phytocompounds exhibiting the surface structure with pore clarity and visible pipes. Transmission Electron Microscope (TEM) images show the uniform dispersed spherical ultrathin nanosheets at the size of 10–20 nm. Further anti‐bacterial analysis results revealed that Centella asiatica phytocompounds coating enhances the anti‐bacterial activity of MWCNT. Prepared Centella asiatica phytocompounds ‐MWCNT possess maximal inhibition and produces high zones of inhibition 11 ± 0.06, 17 ± 0.08, 14 ± 0.07, and 16 ± 0.08 mm against four food‐spoiling bacterial clinical pathogens Salmonella typhi, Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumonia respectively. Centella asiatica phytocompounds conjugated‐MWCNT spin‐coated packaging showed good preservation properties. Centella asiatica phytocompounds conjugated with MWCNTs provide antimicrobial properties, enabling the development of novel food packaging materials that can protect food from spoilage, increase food stability, and sustainability, and improve the shelf life of food.","PeriodicalId":20382,"journal":{"name":"Polymers for Advanced Technologies","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141843752","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Farnaz Azadikhah, Maryam Ghaderi, Hesam Khorsandi, Ali Reza Karimi
Water contamination from industrial dyes poses a significant threat to the environment and human health. This study focuses on the development of advanced porous cross‐linked chitosan‐based hydrogels and superparamagnetic hydrogel nanocomposites for efficient removal of indigo carmine (IC) dye from water. The hydrogels were cross‐linked using benzophenonetetracarboxylic dianhydride (BTDA) and incorporated functionalized magnetic iron nanoparticles (CP‐MNPs). A comparative study revealed that the superparamagnetic hydrogel nanocomposite exhibited superior performance in IC dye adsorption. Higher IC removal efficiencies were observed at lower amounts of cross‐linker, pH, and adsorbent dosage. The superparamagnetic hydrogel nanocomposite demonstrated superior IC dye adsorption compared with the chitosan hydrogel. The adsorption process followed a pseudo‐second‐order kinetic model and Langmuir isotherm model. Thermodynamic data indicated that the adsorption onto the superparamagnetic hydrogel nanocomposite was endothermic and spontaneous, making it a promising material for environmental applications.
工业染料造成的水污染对环境和人类健康构成了严重威胁。本研究的重点是开发先进的多孔交联壳聚糖基水凝胶和超顺磁性水凝胶纳米复合材料，以高效去除水中的靛蓝胭脂红（IC）染料。这些水凝胶使用苯并四羧酸二酐（BTDA）进行交联，并加入了功能化的磁性纳米铁粒子（CP-MNPs）。比较研究表明，超顺磁性水凝胶纳米复合材料在 IC 染料吸附方面表现出卓越的性能。在交联剂用量、pH 值和吸附剂用量较低的情况下，IC 去除率较高。与壳聚糖水凝胶相比，超顺磁性水凝胶纳米复合材料表现出更优越的 IC 染料吸附性能。吸附过程遵循伪二阶动力学模型和 Langmuir 等温线模型。热力学数据表明，超顺磁性水凝胶纳米复合材料上的吸附是内热和自发的，使其成为一种具有环境应用前景的材料。
{"title":"Advanced superparamagnetic cross‐linked chitosan‐based biosorbent hydrogel for efficient removal of indigo carmine dye from water: Adsorption isotherms, kinetics, and thermodynamic studies","authors":"Farnaz Azadikhah, Maryam Ghaderi, Hesam Khorsandi, Ali Reza Karimi","doi":"10.1002/pat.6513","DOIUrl":"https://doi.org/10.1002/pat.6513","url":null,"abstract":"Water contamination from industrial dyes poses a significant threat to the environment and human health. This study focuses on the development of advanced porous cross‐linked chitosan‐based hydrogels and superparamagnetic hydrogel nanocomposites for efficient removal of indigo carmine (IC) dye from water. The hydrogels were cross‐linked using benzophenonetetracarboxylic dianhydride (BTDA) and incorporated functionalized magnetic iron nanoparticles (CP‐MNPs). A comparative study revealed that the superparamagnetic hydrogel nanocomposite exhibited superior performance in IC dye adsorption. Higher IC removal efficiencies were observed at lower amounts of cross‐linker, pH, and adsorbent dosage. The superparamagnetic hydrogel nanocomposite demonstrated superior IC dye adsorption compared with the chitosan hydrogel. The adsorption process followed a pseudo‐second‐order kinetic model and Langmuir isotherm model. Thermodynamic data indicated that the adsorption onto the superparamagnetic hydrogel nanocomposite was endothermic and spontaneous, making it a promising material for environmental applications.","PeriodicalId":20382,"journal":{"name":"Polymers for Advanced Technologies","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141844193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Rajendran Thavasimuthu, P. M. Vidhya, S. Sridhar, S. P. Sasirekha, P. Sherubha
The contamination of microplastics (MPs) creates a substantial risk to both the environment and human health, necessitating the development of efficient methods for detecting and categorizing these micro pollutant particles. As a solution, Dense‐UNet with Convolutional Vision Transformer (Dense‐UNet‐CvT), a novel deep learning (DL)‐based model is proposed to detect and classify the MPs by performing the computer vision tasks. The main objective of this work is to enhance the detection accuracy in detecting the MPs classified from the input images. Initially, a holographic MPs image dataset comprising primary classes such as polyethylene (PE), polystyrene (PS), low‐density polyethylene (LDPE), polyhydroxyalkanoate (PHA) is collected for training and evaluating the research model. The images from the dataset are preprocessed by performing image resizing, Recursive Exposure based Sub‐Image Histogram Equalization (RESIHE)‐based image enhancement, Gaussian Adaptive Bilateral Filtering (GABF)‐based denoising to improve the visual quality of the images. The preprocessed images are applied for segmentation using the Dense‐UNet model for performing semantic segmentation. The CvT model is implemented to extract useful features and to perform classification on detecting the known and unknown classes of MPs labeled in the collected dataset. The MPs detection and classification performances are computed in terms of detection rate, accuracy, f1‐score, and precision. The Dense‐UNet‐CvT model achieved 98.22% detection rate, 98.59% accuracy, 98.35% f1‐score, and 98.76% precision. These performances are compared with the current models for proper validation, in which the research model outperformed all the compared models in terms of performance. Overall, the proposed Dense‐UNet‐CvT model demonstrates superior performance across multiple evaluation metrics, suggesting its effectiveness in detecting and classifying MPs contamination in holographic images.
{"title":"Enhanced classification of microplastic polymers (polyethylene, polystyrene, low‐density polyethylene, polyhydroxyalkanoate) in waterbodies","authors":"Rajendran Thavasimuthu, P. M. Vidhya, S. Sridhar, S. P. Sasirekha, P. Sherubha","doi":"10.1002/pat.6506","DOIUrl":"https://doi.org/10.1002/pat.6506","url":null,"abstract":"The contamination of microplastics (MPs) creates a substantial risk to both the environment and human health, necessitating the development of efficient methods for detecting and categorizing these micro pollutant particles. As a solution, Dense‐UNet with Convolutional Vision Transformer (Dense‐UNet‐CvT), a novel deep learning (DL)‐based model is proposed to detect and classify the MPs by performing the computer vision tasks. The main objective of this work is to enhance the detection accuracy in detecting the MPs classified from the input images. Initially, a holographic MPs image dataset comprising primary classes such as polyethylene (PE), polystyrene (PS), low‐density polyethylene (LDPE), polyhydroxyalkanoate (PHA) is collected for training and evaluating the research model. The images from the dataset are preprocessed by performing image resizing, Recursive Exposure based Sub‐Image Histogram Equalization (RESIHE)‐based image enhancement, Gaussian Adaptive Bilateral Filtering (GABF)‐based denoising to improve the visual quality of the images. The preprocessed images are applied for segmentation using the Dense‐UNet model for performing semantic segmentation. The CvT model is implemented to extract useful features and to perform classification on detecting the known and unknown classes of MPs labeled in the collected dataset. The MPs detection and classification performances are computed in terms of detection rate, accuracy, f1‐score, and precision. The Dense‐UNet‐CvT model achieved 98.22% detection rate, 98.59% accuracy, 98.35% f1‐score, and 98.76% precision. These performances are compared with the current models for proper validation, in which the research model outperformed all the compared models in terms of performance. Overall, the proposed Dense‐UNet‐CvT model demonstrates superior performance across multiple evaluation metrics, suggesting its effectiveness in detecting and classifying MPs contamination in holographic images.","PeriodicalId":20382,"journal":{"name":"Polymers for Advanced Technologies","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141688693","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lignin is one of the most common biopolymers. The application of the electrophysical properties of the polymer is one of the directions of its use. The effect of impurities potassium bromide with an ionic crystal lattice on the electrophysical properties of lignin has been shown. The study of the frequency dependences of the specific electrical conductivity and the components of the complex dielectric permittivity in the frequency range from 6 × 10−2 to 6 × 107 rad s−1 was carried out. The nonadditivity of the electrophysical properties of the lignin‐potassium bromide system has been shown. It is established that the relaxation time of the π‐electrons of the aromatic rings of lignin depends on the content of potassium bromide in the mixture and varies from 1.6 × 10−7 (100% lignin) to 7.5 × 10−4 s (1% of KBr in mixture). The orientation of the positive charge of potassium atom of the KBr dipole atom to the π‐electrons of the benzene ring of lignin leads to change of high‐frequency relaxation time. This effect can be used in frequency filter to eliminate electronic polarization in the high‐frequency region. Thus, the polarization of ionic impurities has a significant effect on the dielectric properties of lignin in the region of medium and high frequencies of alternating electric field.
{"title":"Influence of ionic impurities on the dielectric properties of lignin","authors":"Sergey S. Khviyuzov, Aleksandr S. Volkov","doi":"10.1002/pat.6467","DOIUrl":"https://doi.org/10.1002/pat.6467","url":null,"abstract":"Lignin is one of the most common biopolymers. The application of the electrophysical properties of the polymer is one of the directions of its use. The effect of impurities potassium bromide with an ionic crystal lattice on the electrophysical properties of lignin has been shown. The study of the frequency dependences of the specific electrical conductivity and the components of the complex dielectric permittivity in the frequency range from 6 × 10<jats:sup>−2</jats:sup> to 6 × 10<jats:sup>7</jats:sup> rad s<jats:sup>−1</jats:sup> was carried out. The nonadditivity of the electrophysical properties of the lignin‐potassium bromide system has been shown. It is established that the relaxation time of the <jats:italic>π</jats:italic>‐electrons of the aromatic rings of lignin depends on the content of potassium bromide in the mixture and varies from 1.6 × 10<jats:sup>−7</jats:sup> (100% lignin) to 7.5 × 10<jats:sup>−4</jats:sup> s (1% of KBr in mixture). The orientation of the positive charge of potassium atom of the KBr dipole atom to the <jats:italic>π</jats:italic>‐electrons of the benzene ring of lignin leads to change of high‐frequency relaxation time. This effect can be used in frequency filter to eliminate electronic polarization in the high‐frequency region. Thus, the polarization of ionic impurities has a significant effect on the dielectric properties of lignin in the region of medium and high frequencies of alternating electric field.","PeriodicalId":20382,"journal":{"name":"Polymers for Advanced Technologies","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141502636","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Elder Pacheco da Cruz, Felipe Nardo dos Santos, Jaqueline Ferreira de Souza, Estefania Júlia Dierings de Souza, Laura Martins Fonseca, André Ricardo Fajardo, Elessandra Rosa da Zavareze, Alvaro Renato Guerra Dias
Polymer concentration and aging time of polymeric solutions are crucial factors that can influence their viscosity, playing an essential role in the fabrication of electrospun nanofibers. Based on this, herein we evaluated the impact of aging time (24 and 48 h) and pea starch concentration (10%, 20%, and 30%, wt/vol) on the polymeric solutions to produce electrospun nanofibers. Solutions were evaluated by rheology, electrical conductivity, and degree of substitution. The nanofibers were analyzed by morphology, size distribution, chemical nature, and thermal properties. The degree of substitution of starches varied from 1.17 to 1.56. Overall, electrical conductivity decreased with increasing starch concentration and aging time of the polymeric solutions. The use of 10% starch displayed a transition from capsules to fibers, while 20% and 30% starch were able to manufacture homogenous, cylindrical, and random nanofibers with diameters varying from 89 to 373 nm. A significant impact of viscosity was not observed; on the other hand, aging time increased the average diameter of nanofibers. Besides, the fabricated nanofibers showed a lower decomposition temperature than raw starch. The fabricated nanofibers have great potential as wall materials for the encapsulation of different compounds and applications in the biomedical and food sectors.
{"title":"Impact of concentration and aging time of pea starch‐based polymeric solutions on the fabrication of electrospun nanofibers","authors":"Elder Pacheco da Cruz, Felipe Nardo dos Santos, Jaqueline Ferreira de Souza, Estefania Júlia Dierings de Souza, Laura Martins Fonseca, André Ricardo Fajardo, Elessandra Rosa da Zavareze, Alvaro Renato Guerra Dias","doi":"10.1002/pat.6479","DOIUrl":"https://doi.org/10.1002/pat.6479","url":null,"abstract":"Polymer concentration and aging time of polymeric solutions are crucial factors that can influence their viscosity, playing an essential role in the fabrication of electrospun nanofibers. Based on this, herein we evaluated the impact of aging time (24 and 48 h) and pea starch concentration (10%, 20%, and 30%, wt/vol) on the polymeric solutions to produce electrospun nanofibers. Solutions were evaluated by rheology, electrical conductivity, and degree of substitution. The nanofibers were analyzed by morphology, size distribution, chemical nature, and thermal properties. The degree of substitution of starches varied from 1.17 to 1.56. Overall, electrical conductivity decreased with increasing starch concentration and aging time of the polymeric solutions. The use of 10% starch displayed a transition from capsules to fibers, while 20% and 30% starch were able to manufacture homogenous, cylindrical, and random nanofibers with diameters varying from 89 to 373 nm. A significant impact of viscosity was not observed; on the other hand, aging time increased the average diameter of nanofibers. Besides, the fabricated nanofibers showed a lower decomposition temperature than raw starch. The fabricated nanofibers have great potential as wall materials for the encapsulation of different compounds and applications in the biomedical and food sectors.","PeriodicalId":20382,"journal":{"name":"Polymers for Advanced Technologies","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141502638","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Electric field plays a pivotal role in electrospinning to produce the desired micro and nanofibers, hence, a tricipital‐needle spinneret was developed to improve electric field distribution and productivity in this work. The effects of electric field distribution induced by spinneret configuration on jet motion, fiber morphology, and properties of electrospun TPU fibrous membrane at different applied voltages were investigated by simulation and experiment. The simulation results show that the designed tricipital‐needle spinneret weakens the electric field near the needle tip and strengthens the electric field in the whipping region in comparison to the single‐needle spinneret, exhibiting a relatively uniform electric field distribution. The experimental results demonstrate that the fiber diameter prepared by the tricipital‐needle spinneret at the corresponding voltage is smaller than that of the single‐needle spinneret due to the improved electric field distribution. Moreover, the fibrous membrane prepared by the tricipital‐needle spinneret shows excellent tensile properties (7 MPa tensile stress and 401% breaking elongation), air permeability (85.32 mm s−1) and water vapor permeability (6.7 kg m−2 d−1). Therefore, the electrospinning system with the tricipital‐needle spinneret not only increases the fiber productivity, but also improves the electric field distribution and endows the fibrous membrane with better properties, which can widen the applications of electrospun TPU fibrous membrane and also provides a new approach for the performance design of other electrospun fibers.
{"title":"Effect of improved electric field distribution on jet motion, fiber morphology, and properties of electrospun thermoplastic polyurethane fibrous membrane","authors":"Xiang Li, Liqin Lou","doi":"10.1002/pat.6483","DOIUrl":"https://doi.org/10.1002/pat.6483","url":null,"abstract":"Electric field plays a pivotal role in electrospinning to produce the desired micro and nanofibers, hence, a tricipital‐needle spinneret was developed to improve electric field distribution and productivity in this work. The effects of electric field distribution induced by spinneret configuration on jet motion, fiber morphology, and properties of electrospun TPU fibrous membrane at different applied voltages were investigated by simulation and experiment. The simulation results show that the designed tricipital‐needle spinneret weakens the electric field near the needle tip and strengthens the electric field in the whipping region in comparison to the single‐needle spinneret, exhibiting a relatively uniform electric field distribution. The experimental results demonstrate that the fiber diameter prepared by the tricipital‐needle spinneret at the corresponding voltage is smaller than that of the single‐needle spinneret due to the improved electric field distribution. Moreover, the fibrous membrane prepared by the tricipital‐needle spinneret shows excellent tensile properties (7 MPa tensile stress and 401% breaking elongation), air permeability (85.32 mm s<jats:sup>−1</jats:sup>) and water vapor permeability (6.7 kg m<jats:sup>−2</jats:sup> d<jats:sup>−1</jats:sup>). Therefore, the electrospinning system with the tricipital‐needle spinneret not only increases the fiber productivity, but also improves the electric field distribution and endows the fibrous membrane with better properties, which can widen the applications of electrospun TPU fibrous membrane and also provides a new approach for the performance design of other electrospun fibers.","PeriodicalId":20382,"journal":{"name":"Polymers for Advanced Technologies","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141502637","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xiangbin Zhang, Lang Xu, Qing Sun, Jian Zhang, Jiawei Sheng
Ceramic polyolefin composites have the capability to transform into hard ceramics when exposed to fire conditions. During the ceramization process, the formation of new crystalline phase plays a crucial role in enhancing flame‐retardant and ceramifiable properties. Consequently, ceramic polyolefin composites show great potential for the applications in fire‐resistant wires and cables. In this article, the incorporation of the compound flame retardant consisting of ammonium polyphosphate/melamine cyanurate/zinc borate (APP/MCA/ZB) was found to enhance the flame retardancy and ceramization of polyethylene/wollastonite fiber/phosphate glass frits (PE/WF/PGF) composites. The results indicated that ceramifiable flame‐retarding PE composites with compound flame retardant exhibited superior flame retardancy compared to pure PE and PE composites with a single flame retardant. Specifically, the limiting oxygen index (LOI) was significantly increased to 26.8%, and the vertical combustion test rating in UL‐94 (test for flammability of plastic materials for parts in devices and appliances) reached V‐0. During the heating process, ZB thermally decomposed to produce 2ZnO ⋅ 3B2O3, which reacted with CaSiO3 to form a silicate glass intermediate phase (CaO ⋅ SiO2 ⋅ 2ZnO ⋅ 3B2O3). APP thermally decomposed to produce (HPO3)n, which reacted with 2ZnO ⋅ 3B2O3 to form a phosphate glass intermediate phase (nP2O5 ⋅ 2ZnO ⋅ 3B2O3). These two glass phases experienced a eutectic reaction with WF, ultimately producing the formation of a new crystalline phase of calcium zinc phosphate (CZP, Ca19Zn2(PO4)14). This newly formed CZP phase made sintered ceramics more compact and had higher flexural strength. The flexural strength of ceramic residues after sintering was 11.68 MPa, meeting the requirements for practical applications.
{"title":"Effect of crystalline phase formed by compound flame retardant on the flame retardancy and ceramization of polyethylene composites","authors":"Xiangbin Zhang, Lang Xu, Qing Sun, Jian Zhang, Jiawei Sheng","doi":"10.1002/pat.6485","DOIUrl":"https://doi.org/10.1002/pat.6485","url":null,"abstract":"Ceramic polyolefin composites have the capability to transform into hard ceramics when exposed to fire conditions. During the ceramization process, the formation of new crystalline phase plays a crucial role in enhancing flame‐retardant and ceramifiable properties. Consequently, ceramic polyolefin composites show great potential for the applications in fire‐resistant wires and cables. In this article, the incorporation of the compound flame retardant consisting of ammonium polyphosphate/melamine cyanurate/zinc borate (APP/MCA/ZB) was found to enhance the flame retardancy and ceramization of polyethylene/wollastonite fiber/phosphate glass frits (PE/WF/PGF) composites. The results indicated that ceramifiable flame‐retarding PE composites with compound flame retardant exhibited superior flame retardancy compared to pure PE and PE composites with a single flame retardant. Specifically, the limiting oxygen index (LOI) was significantly increased to 26.8%, and the vertical combustion test rating in UL‐94 (test for flammability of plastic materials for parts in devices and appliances) reached V‐0. During the heating process, ZB thermally decomposed to produce 2ZnO ⋅ 3B<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>, which reacted with CaSiO<jats:sub>3</jats:sub> to form a silicate glass intermediate phase (CaO ⋅ SiO<jats:sub>2</jats:sub> ⋅ 2ZnO ⋅ 3B<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>). APP thermally decomposed to produce (HPO<jats:sub>3</jats:sub>)<jats:sub>n</jats:sub>, which reacted with 2ZnO ⋅ 3B<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> to form a phosphate glass intermediate phase (nP<jats:sub>2</jats:sub>O<jats:sub>5</jats:sub> ⋅ 2ZnO ⋅ 3B<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>). These two glass phases experienced a eutectic reaction with WF, ultimately producing the formation of a new crystalline phase of calcium zinc phosphate (CZP, Ca<jats:sub>19</jats:sub>Zn<jats:sub>2</jats:sub>(PO<jats:sub>4</jats:sub>)<jats:sub>14</jats:sub>). This newly formed CZP phase made sintered ceramics more compact and had higher flexural strength. The flexural strength of ceramic residues after sintering was 11.68 MPa, meeting the requirements for practical applications.","PeriodicalId":20382,"journal":{"name":"Polymers for Advanced Technologies","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141523178","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
T. Angelin Swetha, Abhispa Bora, V. Ananthy, Kumar Ponnuchamy, Govarthanan Muthusamy, A. Arun
Plastic is a widely available material in every aspect of life, and its long‐term usage is an important threat to the environment. An enormous quantity of plastic waste has been discharged into the environment throughout the world, resulting in global white pollution. The weathering of accumulated plastic waste in the environment, which can further break down into small fragments like microplastics and nanoplastics, will harm the ecosystem and humans. Therefore, the production and disposal of plastics need to be considered. Bioplastics are increasingly being used as an alternative to conventional plastics; their primary purpose is to solve pollution‐related problems with plastics. Bioplastics (BPs) are an adequate substitute for traditional plastics since they have less carbon footprint and are readily biodegradable, but not all bioplastics can degrade entirely in the natural environment. Due to less environmental impact, bioplastics are defined as polymers produced by using renewable feedstocks or by microorganisms. BP has a wide range of applications in the medical, automotive, and food packaging industries, and it has the potential impact on effect of development of low‐carbon environment. The standards bioplastics must meet to be called compostable or biodegradable are determined by certified worldwide standard processes. The primary purpose of this review is to focus on bioplastics as an alternative tool to plastic—its types, structure, characteristics, degradation behavior, standard techniques, feedstock used for the production of bioplastic, process for its development, and limitation of bioplastics.
{"title":"A review of bioplastics as an alternative to petrochemical plastics: Its types, structure, characteristics, degradation, standards, and feedstocks","authors":"T. Angelin Swetha, Abhispa Bora, V. Ananthy, Kumar Ponnuchamy, Govarthanan Muthusamy, A. Arun","doi":"10.1002/pat.6482","DOIUrl":"https://doi.org/10.1002/pat.6482","url":null,"abstract":"Plastic is a widely available material in every aspect of life, and its long‐term usage is an important threat to the environment. An enormous quantity of plastic waste has been discharged into the environment throughout the world, resulting in global white pollution. The weathering of accumulated plastic waste in the environment, which can further break down into small fragments like microplastics and nanoplastics, will harm the ecosystem and humans. Therefore, the production and disposal of plastics need to be considered. Bioplastics are increasingly being used as an alternative to conventional plastics; their primary purpose is to solve pollution‐related problems with plastics. Bioplastics (BPs) are an adequate substitute for traditional plastics since they have less carbon footprint and are readily biodegradable, but not all bioplastics can degrade entirely in the natural environment. Due to less environmental impact, bioplastics are defined as polymers produced by using renewable feedstocks or by microorganisms. BP has a wide range of applications in the medical, automotive, and food packaging industries, and it has the potential impact on effect of development of low‐carbon environment. The standards bioplastics must meet to be called compostable or biodegradable are determined by certified worldwide standard processes. The primary purpose of this review is to focus on bioplastics as an alternative tool to plastic—its types, structure, characteristics, degradation behavior, standard techniques, feedstock used for the production of bioplastic, process for its development, and limitation of bioplastics.","PeriodicalId":20382,"journal":{"name":"Polymers for Advanced Technologies","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141523181","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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