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Publication Date: 0
pp. 104-118
Mohammadi, A. ,
Hosseini, D. ,
Sarfjoo, Mohammad Reza ,
Mirsafaei, Razieh Publication Date: 0
Corrosion is a common phenomenon between materials and substances in their environment. Corrosion limits the use of metals for various purposes and increases costs in industries. Many advanced methods have been reported to prevent the corrosion of metal tools. This chapter discusses many topics related to corrosion mechanisms, inhibition routes, corrosion analysis, and mechanisms of waterborne polyurethane and its composites for corrosion protection. Waterborne polyurethane is an eco-friendly polymer that is ideal for a wide range of applications due to its properties, such as flexibility at low temperatures, moisture resistance, resistance to pH changes, quick drying, and easy cleaning. To create an effective coating, it is necessary to prepare highly stable dispersions with practical inhibitory effects, proper packing, high cross-linking density, suitable additive content, and strong adhesion to the substrate. In this chapter, the current literature and research on using waterborne polyurethane and its composites as an anti-corrosion coating are studied in detail to provide a comprehensive overview of how anticorrosion coatings work and what can improve their anti-corrosion properties. © 2023 Nova Science Publishers, Inc.
Publication Date: 0
41pp. 177-204
Hole Transport Materials (HTMs) play a pivotal role in a diverse array of cutting-edge optoelectronic devices prevalent in today's technological landscape. These materials are indispensable for the functionality and performance optimization of various technologies, including displays like Organic Light-Emitting Diodes (OLEDs) and photovoltaic devices like Perovskite Solar Cells (PSCs). The continuous advancement of OLEDs and PSCs over recent decades has spurred the innovation and development of a multitude of HTMs, each characterized by unique structural features. Presently, a notable trend is observed in the utilization of specific small organic molecules, such as carbazoles, as constituents of HTMs. Carbazole-based HTMs exhibit exceptional photovoltaic properties when compared to their counterparts and can be synthesized at a reduced cost, thus driving further exploration and refinement in this domain. Consequently, there is a concerted effort to gain comprehensive insights into the characteristics and capabilities of this category of HTMs, with a particular emphasis on Carbazole-Based Hole Transport Layers (HTLs). Therefore, Leveraging the intrinsic attributes of Carbazole-Based HTLs, researchers have focused on elucidating critical parameters such as Highest Occupied Molecular Orbital (HOMO)-Lowest Unoccupied Molecular Orbital (LUMO) energy levels, Glass Transition Temperatures (Tg), hole mobilities, among others. These data serve as invaluable assets for researchers engaged in interdisciplinary fields spanning chemistry, materials science, electrical engineering, and physics. This investigation stands as a succinct yet comprehensive resource, delving into the intricacies of Carbazole-Based HTLs within the contexts of OLEDs and PSCs. By offering valuable insights and understanding into the design and optimization of HTMs, this study serves as a guiding beacon for researchers, catalyzing further advancements in the field of optoelectronics. © 2024 Nova Science Publishers, Inc. All rights reserved.
Publication Date: 0
Engineering Materials (16121317) pp. 119-135
Solar cells based on semiconductor heterojunction demonstrate tunable interfaces and high efficiency, showing great potentials in future applications. In heterojunction solar cells, charge transport materials play critical roles in carrier conductivity, recombination kinetics, and charge collection efficiency, which in turn significantly influence the photovoltaic parameters as well as the stability of solar cells. Traditional inorganic and molecular conductors exhibit high promises in optoelectronic properties, however, they are somewhat facing challenges in high material cost, poor device stability, and sophisticated fabricating processes. Alternatively, conducting polymers have been recently recognized as promising charge transport materials due to their advantages of high conductivity, tunable work function, controllable transmittance, and high stability. Careful design and optimization of polymer chemical structures have promoted fast development in tuning their optoelectronic properties and enhancing photovoltaic performance. Therefore, in this chapter, we summarize the recent progress of strategies in designing new conducting polymer materials as a charge transport medium for solar cell application. The current challenges and prospects in the future development of polymer-based charge conductors are discussed. © 2022, The Author(s), under exclusive license to Springer Nature Switzerland AG.
Publication Date: 0
Engineering Materials (16121317) pp. 365-413
Electrically conductive epoxy thermosets are getting widespread consideration due to the fast-growing advanced engineering material industry. There are known platforms for encapsulating semiconductors, equipment constituents, electric circuit board substances, aerospace, etc. Currently, various efforts are being made to manufacture conductive epoxy-based nanocomposites, and a systematic and comprehensive understanding is required to move the achievements a step ahead. The conduction mechanism appears as a result of conductive network formation created in the presence of a specific type of additives, namely electrically conductive fillers. Conductive fillers are powders, fibers, and other materials added to epoxy resin to make it easier for electrons to pass through. This chapter describes how the electrical conductance of epoxy thermosets is improved using different types of conductive fillers. The emphasis is on conventional electrically conductive agents (e.g., metals, carbonaceous fillers, and intrinsically conductive polymers) as well as green ionic mixtures, including multi-functioning ionic liquids and deep eutectic solvents. The latter category is important since ionic mixtures can play simultaneously as epoxy hardening compounds and curing catalysts, in addition to their role as electrically conductive agents. Numerous examples of recent and current research activities are given to introduce a complete background of achievement. © 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.
Polyurethanes (PUs) are one of the most diverse categories of polymers. They are available in different forms, such as adhesives, coatings, elastomers, and foams. PUs have unique properties such as desired mechanical, chemical, and abrasion resistance properties. But one of the disadvantages of typical PUs is using organic solvents, which are harmful to human health and the environment. In this regard, the researchers introduced and developed an environmentally friendly alternative to solvent-based PUs, called waterborne polyurethanes (WBPUs). WBPUs, without or with little volatile organic compounds (VOCs), can form thin films with excellent adhesion on many substrates, including metal, glass, and wood at room temperature. Other characteristics of WBPUs are low viscosity, non-toxicity, nonflammability, and cost-effectiveness. Due to the non-dissolution of typical PUs in water, it is necessary to use specific strategies to disperse them in water, by using various processes and raw materials. In this chapter, after an introduction to waterborne polyurethanes, their structure, required raw materials, synthesis methods, and various applications are discussed. In the end, the challenges of this type of polyurethanes are addressed, especially in the preparation process and their industrialization. © 2023 Nova Science Publishers, Inc.
Garza, Andrea Rodríguez ,
Zavaleta, Gabriel Alejandro Nagore ,
Haider, Farhan ,
Mohammadi, A. ,
Burujeny, S.B. Publication Date: 0
Waterborne polyurethanes (WBPUs) have been studied as potential lightresponsive polymers due to their outstanding performance after incorporating light-sensitive components without decreasing their mechanical and physical properties. Photoluminescent WBPUs are lightresponsive WBPUs that can be synthesized by adding nanofillers such as carbon quantum dots and incorporating fluorophores like fluorescein, rhodamine, anthraquinone, naphthalene, and benzophenone as chain extenders or as grafting groups. These photoluminescent WBPUs can be applied as surface coatings, labels, LEDs, and fluorescent sensors. Similarly, by covalently bonding a chromophore to the WBPUs matrix, a self-colored WBPU can be synthesized, which is usually a better option than physically blending the WBPU with a coloring dye. By covalent bonding, the self-colored WBPU has lower color migration and higher water resistance and can be used in coatings, packaging, and textiles. Photochromic WBPUs have also attracted considerable attention due to their various potential applications. Photochromic WBPUs have been developed by adding small photochromic molecules (chromophores) within the polymer backbone. Different molecules such as spiropyran, spirooxazine, and azobenzene have been used to synthesize photochromic WBPUs. © 2023 Nova Science Publishers, Inc.
Publication Date: 0
pp. 74-88
A new field of two-dimensional (2D) physics has been opened by 2D atomic crystals represented by graphene in recent years. Despite a relatively short research history, the exceptional electrical and optical characteristics of 2D semiconductors make them highly attractive for electronic and optoelectronic purposes. The electronic and optical properties of 2D semiconducting materials (SCMs) are significantly influenced by the molecular orbital (MO) delocalization and stacking effects. These effects play a crucial role in determining the performance and efficiency of these materials in various applications, including electronics, optoelectronics, and energy devices. The phenomenon of MO delocalization in 2D SCMs refers to the spread of electronic wavefunctions over multiple atoms within the material. In these materials, the interaction between adjacent layers leads to the formation of new electronic states called interlayer coupling or interlayer hybridization. This delocalization affects the electronic band structure of the material, including the position of the conduction and valence bands, the bandgap, and the effective masses of charge carriers. Moreover, the consideration of stacking effects is of utmost importance for 2D SCMs. The stacking arrangement of layers can influence the electronic properties, such as the bandgap, optical properties, and the anisotropy of charge transport of 2D SCMs. These effects can alter the exciton dynamics, light-matter interactions, and emission characteristics of these materials. © 2025 Anuj Kumar and Ram K. Gupta.
In recent years, non-fullerene acceptor materials have garnered significant attention and utilization in organic solar cells (OSCs) devices, primarily owing to their favorable optical properties and the ease of tuning their electronic energy levels through synthetic methods. The utilization of non-fullerene acceptors represents a prominent focal point in the ongoing research and development of bulk-heterojunction OSCs. Notably, recent advancements in this area have led to remarkable enhancements in power conversion efficiency (PCE), with PCE levels surpassing the 20 \% threshold. Perylene diimide (PDI), a prominent example of a non-fullerene acceptor material, has emerged as a subject of extensive investigation due to its favorable attributes such as high electron affinity and excellent charge transport properties. Its widespread study stems from its capacity for efficient light transmission and electron capture. Through an in-depth examination, the article elucidates the impact of PDI-based acceptor materials on OSC device efficiency and outlines the evolving landscape of their application in renewable energy technologies. © 2024 IEEE.
Hydrogels are polymers that are three-dimensionally cross-linked and possess an impressive capacity to absorb large quantities of water or biofluids while maintaining their integrity. Hydrogels have unique properties that make them highly valuable in diverse industries, including food, packaging, pharmaceuticals, agriculture, biomedical and bioengineering applications, manufacture of technical and electronic devices, and adsorbents for the removal of pollutants for environmental applications. In order to effectively improve the properties of hydrogels, two-dimensional (2D) nanomaterials have been introduced into their structure. Incorporating these nanomaterials not only increases the mechanical characteristics of hydrogels but also offers a wide range of versatile properties, such as electrical, thermal, optical, acoustic, magnetic, and more. Metal carbides, nitrides, or carbonitrides (MXenes) are highly regarded among the available 2D nanomaterials due to their exceptional combination of metal conductivity, solubility, high dimensionality, and adjustable properties. Hydrogels incorporated with MXenes offer exciting and versatile properties such as hydrophilicity, metal conductivity, and wide adjustable properties. Moreover, hydrogels, an excellent and versatile platform, can significantly improve the stability of MXene nanosheets. With respect to hydrogel structures and gelation mechanisms, MXene-based hydrogel possesses amazing properties and has great potential for different applications such as energy storage, catalysis, tissue engineering, and so on. © 2024 John Wiley & Sons Ltd.
Ghahfarokhi, F.A. ,
Moslempoor, M. ,
Ahangar, H. ,
Sheibani, E. Publication Date: 0
The escalating global energy consumption is predominantly attributed to the burgeoning population growth, resulting in increased demand for energy resources; hence, the imperative to shift towards sustainable energy sources is emphasized. In this context, solar energy appears particularly promising due to its abundant, clean, and renewable characteristics. One significant aspect of solar cells is hole transport materials (HTMs), where we are currently witnessing a revolution in hole transport materials based on self-Assembled monolayers (SAM-HTMs); this category of materials has significantly contributed to notable enhancements in power conversion efficiencies (PCEs) in inverted perovskite solar cells (PSCs). Despite the fabrication of the first SAM-based PSC occurring in late 2018, SAM-HTMs have emerged as a promising alternative such as PTAA, primarily due to various advantages such, as tunable bandgap, robust interface stability, and easy fabrication. This class of materials holds the potential to advance the energy sector and expedite the rapid industrialization of PSCs. © 2024 IEEE.
Publication Date: 0
pp. 89-101
The field of optoelectronics has experienced remarkable growth and innovation in recent decades, leading to the development of numerous cutting-edge technologies that have transformed various industries. These technologies have had an indelible impact on our daily lives, and environmentally friendly energy solutions. In the meantime, fibers based on semiconductor polymers represent a remarkable class of materials at the promising frontier of polymer science with electronics and optoelectronics. These elongated structures, composed of organic polymers with conjugated molecular architectures, exhibit semiconducting behavior, which makes them pivotal in the realm of modern electronics and optoelectronics. Semiconducting polymer fibers offer a unique blend of characteristics, including mechanical flexibility, low cost, lightweight composition, and the ability to transport electrical charge, which distinguishes them from conventional inorganic semiconductors. Their versatility extends to applications spanning flexible electronics, light-emitting diodes (LEDs), photovoltaic devices, sensors and wearable technology. This innovative class of materials holds the promise of revolutionizing various industries by enabling the development of cutting-edge, lightweight and adaptable electronic and photonic technologies. As research continues to advance, fibers based on semiconductor polymers remain at the forefront of materials science, driving progress toward more flexible and sustainable electronic solutions. © 2025 selection and editorial matter, Ram K. Gupta; individual chapters, the contributors.
Publication Date: 0
pp. 87-91
Biodegradable and biocompatible polyurethanes are a class of polymers that are useful in medical industry. In this study, new biodegradable and nontoxic water dispersed co-poly(ether-urethane-urea)s (PEUU)s were synthesized based on amino acid and peptide moiety. These polymers were prepared via the reaction of L-leucine anhydride cyclopeptid (LAC), polyethylene glycol (PEG), hexamethylene diisocyante (HDI) and serine (S) as dispersing agent. These polymers were characterized by FT-IR, NMR, TGA, DSC, AFM, and DLS. PEUU polymers were synthetized with three different structural architectures and block sequence. The polymer’s particle size dispersions are around 300 nm. The degradation test was carried out in PBS at 37 °C and evaluated by weight loss, viscosity and particle size decrement as well as by AFM. In order to determine cytotoxicity of the polymers, in vitro toxicity of final polymer was assessed using L929 mouse fibroblast cell line. The results showed no cytotoxicity of these polymers. © Springer Nature Switzerland AG 2020.
Moslempoor, M. ,
Ahangar, H. ,
Ghahfarokhi, F.A. ,
Sheibani, E. Publication Date: 0
Significant attention is directed towards advancing dyesensitized solar cells (DSSCs). DSSCs comprise a complex assembly of components, each playing a critical role in facilitating efficient energy conversion. Of particular significance are the hole transport materials (HTMs), which serve as integral components responsible for transporting positive charges within the cell. HTMs encompass various classes of materials, in the meantime small organic compounds have emerged as the forefront contenders for facilitating charge transport in Solid-state dye-synthesized solar cells (ssDSCs).Triphenylamine and carbazol emerge as a prominent candidate, owing to its unique chemical structure and inherent electrondonating properties. Triphenylamine exhibits a pronounced capacity for donating electrons, primarily attributed to the lone pair of nitrogen atoms and the arrangement of three phenyl rings within its molecular framework. This structural configuration facilitates efficient charge transfer mechanisms within the solar cell, consequently enhancing the stability and performance of solid-state dye-sensitized solar cells. © 2024 IEEE.
Nowadays, it is rare to find a place where adhesive is not used. The increasing growth of industries has expanded the need for this helpful substance. Therefore, sources, synthesis, advances, chemistry, and marketing are very important. Waterborne polyurethane adhesive is a versatile material for different applications such as textile, packaging, automotive, transportation, and footwear. This is due to safety considerations for the environment. Excellent chemical, physical and mechanical performances of this advanced material have been drawing large research focus on its chemistry, synthesis, and modification. Changes to raw material, processing, and techniques can enhance the adhesive properties and performance to make it suitable for desired applications. In this book chapter, raw materials, production processes, advances, and modifications in waterborne polyurethane adhesive have been discussed. Recent advances in these kinds of adhesives are comprehensively illustrated. Also, the market forecast and the effect of various factors on its economy have been briefly mentioned. © 2023 Nova Science Publishers, Inc.
Over the course of fifteen selected chapters, this book explores the production, chemistry, and applications of waterborne polyurethanes (WBPUs). The first chapter is a conceptual introduction to WBPUs, and the following eight chapters cover different kinds of waterborne polyurethanes, such as those made with natural and synthetic polymers, polyurethane/acrylic hybrids, waterborne polyurethane nanocomposites, and even light stimuli responsive and conductive WBPUs. The remaining six chapters cover various applications of WBPUs ranging from textile treatment and food packing to biomedical applications such as drug delivery. © 2023 by Nova Science Publishers, Inc. All rights reserved.
Waterborne polyurethane/acrylate hybrids have attracted significant attention due to some features, such as low toxicity, environmental compatibility, and enhanced physical and chemical properties. In comparison with neat WBPUs, WBPU/acrylate hybrids exhibit improved properties, including solvent and alkali resistance and thermal, mechanical and thermos-mechanical properties. Furthermore, the fabrication of WBPU/acrylate hybrids overcomes the polyurethane/ polyacrylate blend problems like phase separation. The WBPU/acrylate hybrids are prepared by a strong chemical bond between the two components of waterborne polyurethane and acrylate monomers. These hybrids are synthesized by different approaches such as interpenetrating networks, seeded emulsion, and semi-emulsion polymerization. In addition, recently, to reduce the toxicity effect of isocyanates, a non-isocyanate method has been also developed to synthesize WBPU/acrylate hybrids. WBPU/acrylate hybrids have outstanding performances, such as excellent adhesion to the substrates, weather stability, durability, flexibility, and abrasion resistance. The purpose of this book chapter is to study raw materials, the synthesis methods, properties, and applications of the waterborne polyurethane/acrylate hybrids. © 2023 Nova Science Publishers, Inc.
Publication Date: 1990
Synthetic Communications (00397911) 20(18)pp. 2789-2797
Commercially available Ceric(IV) Ammonium Nitrate (CAN) catalyzes nucleophilic ring opening of epoxides in primary, secondary and tertiary alcohols under mild conditions. The corresponding β -alkoxy-alcohols were obtained with high regio and stereoselectivity in high yields. © 1990, Taylor & Francis Group, LLC. All rights reserved.
Publication Date: 1991
Tetrahedron (14645416) 47(47)pp. 9861-9866
Ring opening of epoxides with catalytic amounts of Ce(IV) as ceric ammonium nitrate (CAH) are performed efficiently in the presence of water, Thiols and acetic acid under mild conditions. The epoxides are opened with high regio-and stereoselectivity and with good to excellent yields. The products formed from the reaction of polar substituted epoxides in acetic acid were found to be derivative of succinic acid diester. The mechanism of the reaction is believed to be a radical type, involving the formation of an epoxonium radical cation. © 1991.
Publication Date: 1991
Journal of Organometallic Chemistry (0022328X) 412(3)pp. 445-450
The new metallacycle [PtIMe(CH2)4(dppm)], which contains both methylplatinum and platinacyclopentane groups, has been characterized by multinuclear NMR methods. It exists in solution as an equilibrium mixture of the two possible isomers having the fac-[PtC3] stereochemistry. The chelating (CH2)4 ligand is shown to exert a significantly higher trans-influence than the methyl ligand. Molecular mechanics calculations predict a slight preference for the less symmetrical isomer [Me and one CH2 group trans to dppm] over the more symmetrical isomer [two CH2 groups trans to dppm], in agreement with the experimental observations. © 1991.
Publication Date: 1993
Journal of the Chemical Society, Chemical Communications (00224936) (3)pp. 240-241
Different alkenes are epoxidized with high selectivity in the presence of manganese(III) tetraphenylporphyrin-imidazole-sodium periodate- tetrabutylammonium bromide system in CH2Cl2-H2O media, with high yields (80-100%) at room temperature.
Publication Date: 1994
Tetrahedron Letters (00404039) 35(6)pp. 945-948
Epoxidation of various olefins is achieved by tetra-n-butylammonium periodate in the presence of manganese (III) meso- tetraphenylporphyrin and imidazole in CH2Cl2, with high selectivity and yield under mild conditions. © 1994.
Publication Date: 1994
Synthetic Communications (00397911) 24(8)pp. 1065-1077
Primary and secondary benzylic and saturated trimethylsilyl ethers are converted to their carbonyl compounds with AgBrO3 IAICI3 efficiently. p-Hydroquinonetrimethylsilyl ether is also converted with both AgBrO3 IAlCl3 and NaBrO3 IAlCl3 to p-benzoquinone. AgBrO3IAlCl3 is also able to oxidize primary trimethylsilyl ethers to their carboxylic acids. Primary and secondary benzylic trimethylsilyl ethers are also converted to their carbonyl compounds with NaBrO3IAlCl3; AgBrO3 is more efficient and selective oxidant than NaBrO3. © 1994, Taylor & Francis Group, LLC. All rights reserved.
Publication Date: 1994
Synthetic Communications (00397911) 24(4)pp. 489-494
Benzylic and allylic oximes are selectively oxidized with zinc bismuthate in refluxing toluene or the mixture of acetonitrile-toluene to afford the corresponding carbonyl compounds. © 1994, Taylor & Francis Group, LLC. All rights reserved.
Publication Date: 1996
Synthetic Communications (00397911) 26(1)pp. 1-7
3-Carboxypyridinium chlorochromate(CPCC) is an inexpensive, easily prepared and stable reagent With this reagent oximes, phenylhydrazones, p-nitrophenylhydrazones, semicarbazones and azines are converted to their corresponding carbonyl compounds in good to excellent yields.
Publication Date: 1996
Iranian Journal Of Chemistry And Chemical Engineering (10219986) 15(2)pp. 54-56
Metalloporphirins; Cu(TPP),Mn(TPP)Cl,Co(TPP), Fe(TPP)Cl, Zn(TPP), and Mn(OBP)Cl catalyze regio and chemoselective silylation of hydroxy groups with HMDS. Fe(TPP)Cl is the most effective catalyst and silylation occurs immediately in its presence at room temperature.
Publication Date: 1997
Synthesis (00397881) (7)pp. 756-758
Primary and secondary trimethylsilyl and tetrahydropyranyl (THP) ethers are converted to their carbonyl compounds efficiently using 3- carboxypyridinium chlorochromate. Trimethylsilyl ethers are oxidized selectively in the presence of tetrahydropyranyl ethers.
Publication Date: 1997
International Journal of Thermophysics (15729567) 18(5)pp. 1197-1216
A general equation of state, originally proposed for compressed solids by Parsafar and Mason, has been successfully applied to dense fluids. The equation was tested with experimental data for 13 fluids, including polar, nonpolar, saturated and unsaturated hydrocarbons, strongly hydrogen bonded, and quantum fluids. This equation works well for densities larger than the Boyle density ρB [1/ρB = TB dB2(TB)/dT, where B2(TB) is the second virial coefficient at the Boyle temperature, at which B2 = 0] and for a wide temperature range, specifically from the triple point to the highest temperature for which the experimental measurements have been reported. The equation is used to predict some important known regularities for dense fluids, like the common bulk modulus and the common compression points, and the Tait-Murnaghan equation. Regarding the common points, the equation of state predicts that such common points are only a low-temperature characteristic of dense fluids, as verified experimentally. It is also found that the temperature dependence of the parameters of the equation of state differs from those given for the compressed solids. Specifically they are given by Ai(T) = ai + biT + ciT2 - diT ln(T).
Publication Date: 1997
Iranian Polymer Journal (10261265) 6(4)pp. 235-241
Polybutadiene with a narrow molecular weight is synthesized by anionic polymerization of butadiene monomer in cyclohexane at 20 °C using n-butyllithium as initiator. This polymer is statistically functionalized with 4-phenyl-1,2,4-triazoline-3,5-dione by hydrogen abstraction addition reaction (ene reaction) in an extent of 5, 10, and 15%. These functionalized polymers are reacted with acetyl chloride as well as benzoyl chloride in presence of pyridine at room temperature. These reactions lead to the replacement of N-H with acetyl and benzoyl groups. The amount of urazole and acyl incorporation are determined by 1H NMR technique. Some physical properties of these modified polybutadienes are reported.
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