Artículos de revistas sobre el tema "Novel Polymeric Additives"
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Koukoumtzis, Vasilis, Georgia C. Lainioti, George A. Voyiatzis y Joannis K. Kallitsis. "Novel Hybrid Organic–Inorganic Polymeric Coatings Containing Phosphonium or Acidic Groups for Improving Flame Retardancy of Wood". Coatings 13, n.º 4 (9 de abril de 2023): 754. http://dx.doi.org/10.3390/coatings13040754.
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Flame-retardant polymeric coatings with high limiting oxygen index (LOI) were prepared by combining inorganic mineral huntite (H5) and polymeric additives synthesized in the present work into a polymeric formulation. In order to improve the dispersion of the Mg- (and Ca)-based H5 particles, additives containing phosphonium and acidic groups were employed to homogenize the inorganic fillers into the polymer matrix. Specific blend combinations of the commercial matrix Ecrovin® LV 340 eco with huntite and the additives poly(benzyltriphenylphosphonium-co-4-styrene sulfonic acid) P(SSH-co-SSBTPB60) and poly(hexadecyltributylphosphonium-co-4-styrene sulfonic acid) P(SSH-co-SSTBHDPB80), combining acidic and phosphonium groups, led to LOI values of 34.5% and 33.5%, respectively. The novel flame-retardant polymeric coatings inhibited the combustion of the coated wood substrates, which is attributed to the combination of acidic groups that promote the dispersion of inorganic filler in the polymer matrix and phosphonium groups that support the increase in LOI values.
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Nasrollahi, Nazanin, Leila Ghalamchi, Vahid Vatanpour, Alireza Khataee y Maryam Yousefpoor. "Novel polymeric additives in the preparation and modification of polymeric membranes: A comprehensive review". Journal of Industrial and Engineering Chemistry 109 (mayo de 2022): 100–124. http://dx.doi.org/10.1016/j.jiec.2022.02.036.
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Theodore, Ares N. y Mohinder S. Chattha. "Novel polymeric additives for neutralization of acids in engine oils". Industrial & Engineering Chemistry Product Research and Development 25, n.º 1 (marzo de 1986): 41–45. http://dx.doi.org/10.1021/i300021a011.
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Suleiman, Rami K., Akeem Y. Adesina, Arumugam Madhan Kumar, Mohammad Mizanur Rahman, Fadi A. Al-Badour y Bassam El Ali. "Anticorrosion Properties of a Novel Hybrid Sol–Gel Coating on Aluminum 3003 Alloy". Polymers 14, n.º 9 (28 de abril de 2022): 1798. http://dx.doi.org/10.3390/polym14091798.
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In this study, a novel hybrid sol–gel coating on AA3003 substrate was developed and the effects of various waste material additives on the reinforcement of the sol–gel coating and the anticorrosion properties in the saline medium were investigated. Egg shell, crumb rubber, activated carbon obtained for pyrolysis of waste rubber tire, waste rubber tire, cement kiln dust, and ST100 additives were tested as reinforcement materials. The AFM characterization results of the coating formulations on AA3003 alloy revealed enhanced roughness values for the modified coatings as compared to the base coating. Similarly, no significant changes were detected in the Fourier transform infrared spectroscopy (FTIR) absorption peaks of the hybrid polymeric material upon loading it with the waste additives, while slight changes in the hydrophobic properties of the final modified coatings were observed as a result of the modification process. Electrochemical impedance spectroscopy (EIS) results revealed that the hybrid sol–gel coating had a promising potential for the protection of the AA3003 substrate against corrosion in the saline medium. However, the loaded additives negatively affected the corrosion resistance properties of the parent hybrid sol–gel coating. For instance, the egg shell additive had the least negative effect on the barrier properties, whereas the cured coating layer of the sample loaded with cement and clay additives showed some disintegration, inhomogeneity, and low barrier properties on the metal surface.
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Gedan-Smolka, Michaela, Katrin Schubert, Antje Täger y Hagen Marks. "Matrix Bondable Antistatic Additives for Fiber Reinforced Thermosets". Solid State Phenomena 267 (octubre de 2017): 114–18. http://dx.doi.org/10.4028/www.scientific.net/ssp.267.114.
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For electrostatic coating application Sheet Molding Composites (SMC) have to be modified antistatically. By a novel approach several monomeric and polymeric ionic substances were incorporated into the duromeric bulk phase and tested in terms of its antistatic effectiveness. Furthermore the influence of selected additives on the SMC thickening and molding procedure as well as resulting mechanical properties of modified SMC-panels and the powder coating application were studied.
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Fu, Hongyuan, Caiying Chen, Huanyi Zha, Du Yuan, Qian-Feng Gao, Ling Zeng y Chuankun Jia. "Hydrophobic Polymeric Additives toward a Long-Term Robust Carbonaceous Mudstone Slope". Polymers 13, n.º 5 (5 de marzo de 2021): 802. http://dx.doi.org/10.3390/polym13050802.
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Slopes with carbonaceous mudstone (CM) are widely distributed in the southwest of China and have experienced numerous geological disasters in special climate, especially in rainfall conditions. Therefore, novel materials to stabilize CM slopes have attracted increasing interests. However, developing ultra-stable and cost-effective additives for CM slopes is still a great challenge. Herein, a hydrophobic polymeric material (polyvinylidene fluoride, PVDF) is investigated as an additive to enhance the mechanical strength and long-time stability of CM slopes. The PVDF is uniformly dispersed in CM matrix via interfacial interaction. The contact angle of the PVDF-modified carbonaceous mudstone (PVDF-MCM) can reach as high as 103.95°, indicating an excellent hydrophobicity. The unconfined compressive strength (UCS) and tensile strength (TS) of PVDF-MCM have been intensively enhanced to 4.07 MPa and 1.96 MPa, respectively, compared with ~0 MPa of pristine CM. Moreover, the UCS and TS of PVDF-MCM remain at 3.24 MPa and 1.03 MPa even after curing for 28 days in high humidity conditions. Our findings show that the PVDF can improve the hydrophobicity of CM significantly, which leads to super mechanical stability of PVDF-MCM. The excellent performance makes PVDF a promising additive for the development of ultra-stable, long-lifetime and cost-effective carbonaceous mudstone slopes.
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Pötsche, Ing Petra, A. Janke Leibniz, A. A. Bhattacharyya y H. Goering. "Composites Made from Thermoplastic Polymers with Carbon Nanotubes". International Polymer Science and Technology 32, n.º 6 (junio de 2005): 1–9. http://dx.doi.org/10.1177/0307174x0503200601.
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Carbon nanotubes are novel nanoscaled additives with excellent electrical and mechanical properties that make them suitable for endowing polymeric materials with conductivity and for mechanical reinforcement even in very low amounts. This paper describes possibilities for their incorporation in polymers by means of melt processing.
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Valdes-Vidal, Gonzalo, Alejandra Calabi-Floody, Cristian Mignolet-Garrido y Cristobal Bravo-Espinoza. "Enhancing Fatigue Resistance in Asphalt Mixtures with a Novel Additive Derived from Recycled Polymeric Fibers from End-of-Life Tyres (ELTs)". Polymers 16, n.º 3 (30 de enero de 2024): 385. http://dx.doi.org/10.3390/polym16030385.
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Waste-tire textile fibers (WTTF) represent a challenge for the recycling industry since there are currently very few alternatives for their use. In this study, an evaluation of the effect of a new additive developed in two granular formats from WTTF on the fatigue behavior of asphalt mixtures was performed. For the first format of the WTTF-based additive, its effect was evaluated on hot-mix asphalt (HMA), while for the second format of the additive, the effects were evaluated on stone mastic asphalt (SMA). This second format represents an alternative that allows for the total replacement of the cellulose stabilizing additive used in the reference mix. The evaluation of fatigue damage in the mixes was performed using the four-point bending beam (4PB) test specified in European standard EN 12697-24. The test results show that the asphalt mixtures manufactured with WTTF-based additives exhibited a higher capacity to resist load cycles before failure compared to the reference mixtures. Likewise, once the asphalt mixtures were evaluated in a pavement structure by means of an empirical mechanistic analysis, the pavement structures composed of asphalt mixtures with WTTF-based additives showed significant improvements in their durability for the different load axes evaluated. For an average thickness of 15 cm of asphalt mix of a pavement-type structure, the use of the WTTF additive increases the durability of the structures by up to 129% and 112% compared to the HMA and SMA reference mixtures, respectively. These results show that both formats of the WTTF-based admixture improve the fatigue damage resistance of the HMA and SMA asphalt mixtures.
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Thakur, Shubham, Amrinder Singh, Ritika Sharma, Rohan Aurora y Subheet Kumar Jain. "Biosurfactants as a Novel Additive in Pharmaceutical Formulations: Current Trends and Future Implications". Current Drug Metabolism 21, n.º 11 (29 de diciembre de 2020): 885–901. http://dx.doi.org/10.2174/1389200221666201008143238.
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Background: Surfactants are an important category of additives that are used widely in most of the formulations as solubilizers, stabilizers, and emulsifiers. Current drug delivery systems comprise of numerous synthetic surfactants (such as Cremophor EL, polysorbate 80, Transcutol-P), which are associated with several side effects though used in many formulations. Therefore, to attenuate the problems associated with conventional surfactants, a new generation of surface-active agents is obtained from the metabolites of fungi, yeast, and bacteria, which are termed as biosurfactants. Objectives: In this article, we critically analyze the different types of biosurfactants, their origin along with their chemical and physical properties, advantages, drawbacks, regulatory status, and detailed pharmaceutical applications. Methods: 243 papers were reviewed and included in this review. Results: Briefly, Biosurfactants are classified as glycolipids, rhamnolipids, sophorolipids, trehalolipids, surfactin, lipopeptides & lipoproteins, lichenysin, fatty acids, phospholipids, and polymeric biosurfactants. These are amphiphilic biomolecules with lipophilic and hydrophilic ends and are used as drug delivery vehicles (foaming, solubilizer, detergent, and emulsifier) in the pharmaceutical industry. Despite additives, they have some biological activity as well (anti-cancer, anti-viral, anti-microbial, P-gp inhibition, etc.). These biomolecules possess better safety profiles and are biocompatible, biodegradable, and specific at different temperatures. Conclusion: Biosurfactants exhibit good biomedicine and additive properties that can be used in developing novel drug delivery systems. However, more research should be driven due to the lack of comprehensive toxicity testing and high production cost which limits their use.
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Li, Xinyu, Zhongxin Zhang, Zheng Xie, Xinrui Guo, Tianjian Yang, Zhongli Li, Mei Tu y Huaxin Rao. "High Performance and Self-Humidifying of Novel Cross-Linked and Nanocomposite Proton Exchange Membranes Based on Sulfonated Polysulfone". Nanomaterials 12, n.º 5 (2 de marzo de 2022): 841. http://dx.doi.org/10.3390/nano12050841.
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The introduction of inorganic additive or nanoparticles into fluorine-free proton exchange membranes (PEMs) can improve proton conductivity and have considerable effects on the performance of polymer electrolyte membrane fuel cells. Based on the sol–gel method and in situ polycondensation, novel cross-linked PEM and nanocomposite PEMs based on a sulfonated polysulfone (SPSU) matrix were prepared by introducing graphene oxide (GO) polymeric brushes and incorporating Pt-TiO2 nanoparticles into an SPSU matrix, respectively. The results showed that the incorporation of Pt-TiO2 nanoparticles could obviously enhance self-humidifying and thermal stability. In addition, GO polymer brushes fixed on polymeric PEM by forming a cross-linked network structure could not only solve the leakage of inorganic additives during use and compatibility problem with organic polymers, but also significantly improve proton conductivity and reduce methanol permeability of the nanocomposite PEM. Proton conductivity, water uptake and methanol permeability of the nanocomposite PEM can be up to 6.93 mS cm−1, 46.58% and be as low as 1.4157 × 10−6 cm2 s−1, respectively, which represent increases of about 70%, about 22% and a decrease of about 40%, respectively, compared with that of primary SPSU. Therefore, the synergic action of the covalent cross-linking, GO polymer brush and nanoparticles can significantly and simultaneously improve the overall performance of the composite PEM.
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Kazi, Salim N. "Fouling and fouling mitigation of calcium compounds on heat exchangers by novel colloids and surface modifications". Reviews in Chemical Engineering 36, n.º 6 (26 de agosto de 2020): 653–85. http://dx.doi.org/10.1515/revce-2017-0076.
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AbstractFouling is the accumulation of unwanted materials on surfaces that causes detrimental effects on its function. The accumulated materials can be composed of living organisms (biofouling), nonliving substances (inorganic and/or organic), or a combination of both of them. Mineral fouling occurs when a process uses cooling water supersaturated with mineral salt crystals (i.e. hard water). Precipitation ensues on heat transfer surfaces whenever the inversely soluble dissolved calcium salt ions are exposed to high temperature. Mineral salts, dirt, waxes, biofilms, whey proteins, etc. are common deposits on the heat exchanger surfaces, and they create thermal resistance and increase pressure drop and maintenance costs of plants. Fouling of dissolved salts and its mitigation have been studied in detail by varying process parameters, surface materials, coatings on surfaces, additives, etc. by many researchers. In the present stage, researchers have considered polymeric additives, environmental friendly nanoparticles, natural fibers, and thermal conductive coatings (metallic and polymeric) in the study of mitigation of fouling. A better understanding of the problem and the mechanisms that lead to the accumulation of deposits on surfaces will provide opportunities to reduce or even eliminate the problem in certain situations. The present review study has focused on fouling phenomena, environment of fouling, heat exchanger fouling in design, and mitigation of fouling. The findings could support in developing the improved heat exchanger material surfaces, retain efficiency of the heat exchangers, and prolong their continuous operation.
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Takemura, Yuta, Ryota Saito, Angga Hermawan, Keisuke Muramatsu y Wataru Sugimoto. "Size Effect of RuO2-Based 2D Conductive Binder". ECS Meeting Abstracts MA2023-01, n.º 13 (28 de agosto de 2023): 1326. http://dx.doi.org/10.1149/ma2023-01131326mtgabs.
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In an electrode mixture MnO2 is one of the most well studied pseudocapacitive material for aqueous supercapacitors owing to the surface and near surface-confined redox processes. A large amount of conducting additive, generally 20-30 wt% acetylene black, needs to be added to achieve high-rate charge storage. Since the conducting additive does not contribute much to the specific capacitance, this leads to decrease in total energy density of the cell in terms of both mass and volume. Polymeric binders such as PTFE and PVdF are also necessary to fabricate rigid electrode with good contact. As an alternative to these typical conductive binders and polymer binders, we have studied the possibility of using RuO2 nanosheets as a novel inorganic binder with polymeric properties, high electronic conductivity and excellent pseudocapacitive properties. For example, by adding only 10-20 mol% of RuO2 nanosheets to particulate MnO2, a large synergetic effect is observed leading to a high utilization of MnO2 pseudocapacitance.[1] The optimized amount of RuO2 in the composite was 13 wt%, which is much lower than the amount generally used for conductive carbon additives despite the 10 times higher formula weight of RuO2 compared to carbon. In this work, we report the electrochemical properties of nanosheet composite electrodes composed of highly conductive RuO2 nanosheets (RuO2(ns)) and poorly conductive MnO2 nanosheets (MnO2(ns)) with various composition and nanosheet size.
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Varfoloveev, S. D., S. M. Lomakin, P. A. Sakharov y A. V. Khvatov. "Effective chemical methods of fire control: new threats and new solutions". Вестник Российской академии наук 89, n.º 5 (6 de mayo de 2019): 442–48. http://dx.doi.org/10.31857/s0869-5873895442-448.
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This paper discusses the prospective flame retardant systems for polymeric materials, while considering the environmental issues they create. Polymer nanocomposites with carbon nano-additives and layered silicates are presented as a new type of flame retardant system which exhibits a synergistic effect flame retardancy for traditional polymer thermoplasts. Particular attention is paid to the novel intumescent flame retardants based on the oxidized renewable raw materials, which can be successfully used in the manufacture of multi-purpose timber construction and polymer materials.
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Lengert, Ekaterina V., Semyon I. Koltsov, Jie Li, Alexey V. Ermakov, Bogdan V. Parakhonskiy, Ekaterina V. Skorb y Andre G. Skirtach. "Nanoparticles in Polyelectrolyte Multilayer Layer-by-Layer (LbL) Films and Capsules—Key Enabling Components of Hybrid Coatings". Coatings 10, n.º 11 (21 de noviembre de 2020): 1131. http://dx.doi.org/10.3390/coatings10111131.
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Originally regarded as auxiliary additives, nanoparticles have become important constituents of polyelectrolyte multilayers. They represent the key components to enhance mechanical properties, enable activation by laser light or ultrasound, construct anisotropic and multicompartment structures, and facilitate the development of novel sensors and movable particles. Here, we discuss an increasingly important role of inorganic nanoparticles in the layer-by-layer assembly—effectively leading to the construction of the so-called hybrid coatings. The principles of assembly are discussed together with the properties of nanoparticles and layer-by-layer polymeric assembly essential in building hybrid coatings. Applications and emerging trends in development of such novel materials are also identified.
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Cozzarini, Luca, Lucia Marsich y Alessio Ferluga. "Scleroglucan-Based Foam Incorporating Recycled Rigid Polyurethane Waste for Novel Insulation Material Production". Polymers 16, n.º 10 (10 de mayo de 2024): 1360. http://dx.doi.org/10.3390/polym16101360.
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This study details the synthesis and performance evaluation of a novel lightweight thermal and acoustic insulation material, resulting from the combination of a scleroglucan-based hydrogel and recycled rigid polyurethane waste powder. Through a sublimation-driven water-removal process, a porous three-dimensional network structure is formed, showcasing notable thermal and acoustic insulation properties. Experimental data are presented to highlight the material’s performance, including comparisons with commercially available mineral wool and polymeric foams. This material versatility is demonstrated through tunable mechanical, thermal and acoustic characteristics, achieved by strategically adjusting the concentration of the biopolymer and additives. This adaptability positions the material as a promising candidate for different insulation applications. Addressing environmental concerns related to rigid polyurethane waste disposal, the study contributes to the circular economy.
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Jacinto-Valderrama, Rickyn A., Cristina T. Andrade, Mirian Pateiro, José M. Lorenzo y Carlos Adam Conte-Junior. "Recent Trends in Active Packaging Using Nanotechnology to Inhibit Oxidation and Microbiological Growth in Muscle Foods". Foods 12, n.º 19 (4 de octubre de 2023): 3662. http://dx.doi.org/10.3390/foods12193662.
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Muscle foods are highly perishable products that require the use of additives to inhibit lipid and protein oxidation and/or the growth of spoilage and pathogenic microorganisms. The reduction or replacement of additives used in the food industry is a current trend that requires the support of active-packaging technology to overcome novel challenges in muscle-food preservation. Several nano-sized active substances incorporated in the polymeric matrix of muscle-food packaging were discussed (nanocarriers and nanoparticles of essential oils, metal oxide, extracts, enzymes, bioactive peptides, surfactants, and bacteriophages). In addition, the extension of the shelf life and the inhibitory effects of oxidation and microbial growth obtained during storage were also extensively revised. The use of active packaging in muscle foods to inhibit oxidation and microbial growth is an alternative in the development of clean-label meat and meat products. Although the studies presented serve as a basis for future research, it is important to emphasize the importance of carrying out detailed studies of the possible migration of potentially toxic additives, incorporated in active packaging developed for muscle foods under different storage conditions.
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Choudhary, Pritam Dinesh y Harshal Ashok Pawar. "Recently Investigated Natural Gums and Mucilages as Pharmaceutical Excipients: An Overview". Journal of Pharmaceutics 2014 (7 de abril de 2014): 1–9. http://dx.doi.org/10.1155/2014/204849.
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Due to advances in drug delivery technology, currently, excipients are included in novel dosage forms to fulfil specific functions and in some cases they directly or indirectly influence the extent and/or rate of drug release and drug absorption. Recent trends towards use of plant based and natural products demand the replacement of synthetic additives with natural ones. Today, the whole world is increasingly interested in natural drugs and excipients. These natural materials have many advantages over synthetic ones as they are chemically inert, nontoxic, less expensive, biodegradable, and widely available. This review discusses majority of the plant-derived polymeric compounds (gums and mucilage’s), their sources, chemical constituents, uses, and some recent investigations as excipients in novel drug delivery systems.
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Pires, João Ricardo Afonso, Carolina Rodrigues, Isabel Coelhoso, Ana Luisa Fernando y Victor Gomes Lauriano Souza. "Current Applications of Bionanocomposites in Food Processing and Packaging". Polymers 15, n.º 10 (17 de mayo de 2023): 2336. http://dx.doi.org/10.3390/polym15102336.
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Nanotechnology advances are rapidly spreading through the food science field; however, their major application has been focused on the development of novel packaging materials reinforced with nanoparticles. Bionanocomposites are formed with a bio-based polymeric material incorporated with components at a nanoscale size. These bionanocomposites can also be applied to preparing an encapsulation system aimed at the controlled release of active compounds, which is more related to the development of novel ingredients in the food science and technology field. The fast development of this knowledge is driven by consumer demand for more natural and environmentally friendly products, which explains the preference for biodegradable materials and additives obtained from natural sources. In this review, the latest developments of bionanocomposites for food processing (encapsulation technology) and food packaging applications are gathered.
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Baras, Bashayer H., Mary Anne S. Melo, Vivek Thumbigere-Math, Franklin R. Tay, Ashraf F. Fouad, Thomas W. Oates, Michael D. Weir, Lei Cheng y Hockin H. K. Xu. "Novel Bioactive and Therapeutic Root Canal Sealers with Antibacterial and Remineralization Properties". Materials 13, n.º 5 (1 de marzo de 2020): 1096. http://dx.doi.org/10.3390/ma13051096.
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According to the American Dental Association Survey of Dental Services Rendered (published in 2007), 15 million root canal treatment procedures are performed annually. Endodontic therapy relies mainly on biomechanical preparation, chemical irrigation and intracanal medicaments which play an important role in eliminating bacteria in the root canal. Furthermore, adequate obturation is essential to confine any residual bacteria within the root canal and deprive them of nutrients. However, numerous studies have shown that complete elimination of bacteria is not achieved due to the complex anatomy of the root canal system. There are several conventional antibiotic materials available in the market for endodontic use. However, the majority of these antibiotics and antiseptics provide short-term antibacterial effects, and they impose a risk of developing antibacterial resistance. The root canal is a dynamic environment, and antibacterial and antibiofilm materials with long-term effects and nonspecific mechanisms of action are highly desirable in such environments. In addition, the application of acidic solutions to the root canal wall can alter the dentin structure, resulting in a weaker and more brittle dentin. Root canal sealers with bioactive properties come in direct contact with the dentin wall and can play a positive role in bacterial elimination and strengthening of the root structure. The new generation of nanostructured, bioactive, antibacterial and remineralizing additives into polymeric resin-based root canal sealers are discussed in this review. The effects of these novel bioactive additives on the physical and sealing properties, as well as their biocompatibility, are all important factors that are presented in this article.
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Yokoi, Atsushi, Wai Kian Tan, Taichi Kuroda, Go Kawamura, Atsunori Matsuda y Hiroyuki Muto. "Design of Heat-Conductive hBN–PMMA Composites by Electrostatic Nano-Assembly". Nanomaterials 10, n.º 1 (12 de enero de 2020): 134. http://dx.doi.org/10.3390/nano10010134.
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Micro/nanoscale design of composite materials enables alteration of their properties for advanced functional materials. One of the biggest challenges in material design is the controlled decoration of composite materials with the desired functional additives. This study reports on and demonstrates the homogeneous decoration of hexagonal boron nitride (hBN) on poly(methylmethacrylate) (PMMA) and vice versa. The formation of the composite materials was conducted via a low environmental load and a low-energy-consuming, electrostatic nano-assembly method which also enabled the efficient usage of nano-sized additives. The hBN/PMMA and PMMA/hBN composites were fabricated in various size combinations that exhibited percolated and layer-oriented structures, respectively. The thermal conductivity behaviors of hBN/PMMA and PMMA/hBN composites that exhibited good microstructure were compared. The results showed that microstructural design of the composites enabled the modification of their heat-conducting property. This novel work demonstrated the feasibility of fabricating heat-conductive PMMA matrix composites with controlled decoration of hBN sheets, which may provide a platform for further development of heat-conductive polymeric materials.
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Gunathilake, Tharuka, Taiwo O. Akanbi, Hafiz A. R. Suleria, Tim D. Nalder, David S. Francis y Colin J. Barrow. "Seaweed Phenolics as Natural Antioxidants, Aquafeed Additives, Veterinary Treatments and Cross-Linkers for Microencapsulation". Marine Drugs 20, n.º 7 (7 de julio de 2022): 445. http://dx.doi.org/10.3390/md20070445.
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Driven by consumer demand and government policies, synthetic additives in aquafeed require substitution with sustainable and natural alternatives. Seaweeds have been shown to be a sustainable marine source of novel bioactive phenolic compounds that can be used in food, animal and aqua feeds, or microencapsulation applications. For example, phlorotannins are a structurally unique polymeric phenolic group exclusively found in brown seaweed that act through multiple antioxidant mechanisms. Seaweed phenolics show high affinities for binding proteins via covalent and non-covalent bonds and can have specific bioactivities due to their structures and associated physicochemical properties. Their ability to act as protein cross-linkers means they can be used to enhance the rheological and mechanical properties of food-grade delivery systems, such as microencapsulation, which is a new area of investigation illustrating the versatility of seaweed phenolics. Here we review how seaweed phenolics can be used in a range of applications, with reference to their bioactivity and structural properties.
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Patel, Mahesh Chandra, Mohammed Abdalla Ayoub, Mazlin Bt Idress y Anirbid Sircar. "Development of a Novel Surfactant-Based Viscoelastic Fluid System as an Alternative Nonpolymeric Fracturing Fluid and Comparative Analysis with Traditional Guar Gum Gel Fluid". Polymers 15, n.º 11 (25 de mayo de 2023): 2444. http://dx.doi.org/10.3390/polym15112444.
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Surfactant-based viscoelastic (SBVE) fluids have recently gained interest from many oil industry researchers due to their polymer-like viscoelastic behaviour and ability to mitigate problems of polymeric fluids by replacing them during various operations. This study investigates an alternative SBVE fluid system for hydraulic fracturing with comparable rheological characteristics to conventional polymeric guar gum fluid. In this study, low and high surfactant concentration SBVE fluid and nanofluid systems were synthesized, optimized, and compared. Cetyltrimethylammonium bromide and counterion inorganic sodium nitrate salt, with and without 1 wt% ZnO nano-dispersion additives, were used; these are entangled wormlike micellar solutions of cationic surfactant. The fluids were divided into the categories of type 1, type 2, type 3, and type 4, and were optimized by comparing the rheological characteristics of different concentration fluids in each category at 25 °C. The authors have reported recently that ZnO NPs can improve the rheological characteristics of fluids with a low surfactant concentration of 0.1 M cetyltrimethylammonium bromide by proposing fluids and nanofluids of type 1 and type 2. In addition, conventional polymeric guar gum gel fluid is prepared in this study and analyzed for its rheological characteristics. The rheology of all SBVE fluids and the guar gum fluid was analyzed using a rotational rheometer at varying shear rate conditions from 0.1 to 500 s−1 under 25 °C, 35 °C, 45 °C, 55 °C, 65 °C, and 75 °C temperature conditions. The comparative analysis section compares the rheology of the optimal SBVE fluids and nanofluids in each category to the rheology of polymeric guar gum fluid for the entire range of shear rates and temperature conditions. The type 3 optimum fluid with high surfactant concentration of 0.2 M cetyltrimethylammonium bromide and 1.2 M sodium nitrate was the best of all the optimum fluids and nanofluids. This fluid shows comparative rheology to guar gum fluid even at elevated shear rate and temperature conditions. The comparison of average viscosity values under a different group of shear rate conditions suggests that the overall optimum SBVE fluid prepared in this study is a potential nonpolymeric viscoelastic fluid candidate for hydraulic fracturing operation that could replace polymeric guar gum fluids.
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Elganidi, Ibrahim, Basem Elarbe, Norida Ridzuan y Norhayati Abdullah. "Optimisation of reaction parameters for a novel polymeric additives as flow improvers of crude oil using response surface methodology". Journal of Petroleum Exploration and Production Technology 12, n.º 2 (29 de octubre de 2021): 437–49. http://dx.doi.org/10.1007/s13202-021-01349-1.
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AbstractIn recent years, polymeric additives have received considerable attention as a wax control approach to enhance the flowability of waxy crude oil. Furthermore, the satisfactory model for predicting maximum yield in free radical polymerisation has been challenging due to the complexity and rigours of classic kinetic models. This study investigated the influence of operating parameters on a novel synthesised polymer used as a wax deposition inhibitor in a crude oil pipeline. Response surface methodology (RSM) was used to develop a polynomial regression model and investigate the effect of reaction temperature, reaction time, and initiator concentration on the polymerisation yield of behenyl acrylate-co-stearyl methacrylate-co-maleic anhydride (BA-co-SMA-co-MA) polymer by using central composite design (CCD) approach. The modelled optimisation conditions were reaction time of 8.1 h, reaction temperature of 102 °C, and initiator concentration of 1.57 wt%, with the corresponding yield of 93.75%. The regression model analysis (ANOVA) detected an R2 value of 0.9696, indicating that the model can clarify 96.96% of the variation in data variation and does not clarify only 3% of the total differences. Three experimental validation runs were carried out using the optimal conditions, and the highest average yield is 93.20%. An error of about 0.55% was observed compared with the expected value. Therefore, the proposed model is reliable and can predict yield response accurately. Furthermore, the regression model is highly significant, indicating a strong agreement between the expected and experimental values of BA-co-SMA-co-MA yield. Consequently, this study’s findings can help provide a robust model for predicting maximum polymerisation yield to reduce the cost and processing time associated with the polymerisation process.
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Zhou, Xiaoqing, Qi Zhang, Rong Xu, Dong Chen, Shilong Hao, Fude Nie y Hongzhen Li. "A Novel Spherulitic Self-Assembly Strategy for Organic Explosives: Modifying the Hydrogen Bonds by Polymeric Additives in Emulsion Crystallization". Crystal Growth & Design 18, n.º 4 (16 de marzo de 2018): 2417–23. http://dx.doi.org/10.1021/acs.cgd.8b00044.
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Patel, Mahesh Chandra, Mohammed Abdalla Ayoub, Anas Mohammed Hassan y Mazlin Bt Idress. "A Novel ZnO Nanoparticles Enhanced Surfactant Based Viscoelastic Fluid Systems for Fracturing under High Temperature and High Shear Rate Conditions: Synthesis, Rheometric Analysis, and Fluid Model Derivation". Polymers 14, n.º 19 (26 de septiembre de 2022): 4023. http://dx.doi.org/10.3390/polym14194023.
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Surfactant-based viscoelastic (SBVE) fluids are innovative nonpolymeric non-newtonian fluid compositions that have recently gained much attention from the oil industry. SBVE can replace traditional polymeric fracturing fluid composition by mitigating problems arising during and after hydraulic fracturing operations are performed. In this study, SBVE fluid systems which are entangled with worm-like micellar solutions of cationic surfactant: cetrimonium bromide or CTAB and counterion inorganic sodium nitrate salt are synthesized. The salt reagent concentration is optimized by comparing the rheological characteristics of different concentration fluids at 25 °C. The study aims to mitigate the primary issue concerning these SBVE fluids: significant drop in viscosity at high temperature and high shear rate (HTHS) conditions. Hence, the authors synthesized a modified viscoelastic fluid system using ZnO nanoparticle (NPs) additives with a hypothesis of getting fluids with improved rheology. The rheology of optimum fluids of both categories: with (0.6 M NaNO3 concentration fluid) and without (0.8 M NaNO3 concentration fluid) ZnO NPs additives were compared for a range of shear rates from 1 to 500 Sec−1 at different temperatures from 25 °C to 75 °C to visualize modifications in viscosity values after the addition of NPs additives. The rheology in terms of viscosity was higher for the fluid with 1% dispersed ZnO NPs additives at all temperatures for the entire range of shear rate values. Additionally, rheological correlation function models were derived for the synthesized fluids using statistical analysis methods. Subsequently, Herschel–Bulkley models were developed for optimum fluids depending on rheological correlation models. In the last section of the study, the pressure-drop estimation method is described using given group equations for laminar flow in a pipe depending on Herschel–Bulkley-model parameters have been identified for optimum fluids are consistency, flow index and yield stress values.
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Sylvester, Kevin. "(Invited) Electrocoat for Low-Cost, Water-Based Li-Ion Battery Electrode Manufacturing". ECS Meeting Abstracts MA2022-02, n.º 6 (9 de octubre de 2022): 636. http://dx.doi.org/10.1149/ma2022-026636mtgabs.
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The state-of-the-art manufacture of lithium ion battery (LIB) cathodes is slot-die coating of a high viscosity slurry consisting of active materials, conductive additives, and a polymeric binder in N-methyl-2-pyrrolidone (NMP). The operation of slot-die is costly due to the 2-coat/2-cure electrode processing and the use of NMP solvent, which is an expensive consumable with serious health concerns. An alternative approach is the use of waterborne binder systems applied to metal foils using electrocoat. Electrocoat is an electrophoretic process widely recognized to be a high-throughput, low cost, coating application method that allows simultaneous coating of both sides of metal. This presentation will demonstrate the development of novel binders to enable electrodeposited lithium-ion battery electrode coating system. The novel binders were designed for flexibility, ionic mobility, and compatibility with high-energy density active materials and formulated to result in stable water-based cathode coating systems.
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Niemczyk-Soczynska, Beata, Angelika Zaszczyńska, Konrad Zabielski y Pawel Sajkiewicz. "Hydrogel, Electrospun and Composite Materials for Bone/Cartilage and Neural Tissue Engineering". Materials 14, n.º 22 (15 de noviembre de 2021): 6899. http://dx.doi.org/10.3390/ma14226899.
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Injuries of the bone/cartilage and central nervous system are still a serious socio-economic problem. They are an effect of diversified, difficult-to-access tissue structures as well as complex regeneration mechanisms. Currently, commercially available materials partially solve this problem, but they do not fulfill all of the bone/cartilage and neural tissue engineering requirements such as mechanical properties, biochemical cues or adequate biodegradation. There are still many things to do to provide complete restoration of injured tissues. Recent reports in bone/cartilage and neural tissue engineering give high hopes in designing scaffolds for complete tissue regeneration. This review thoroughly discusses the advantages and disadvantages of currently available commercial scaffolds and sheds new light on the designing of novel polymeric scaffolds composed of hydrogels, electrospun nanofibers, or hydrogels loaded with nano-additives.
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Ditzinger, Felix, Catherine Dejoie, Dubravka Sisak Jung y Martin Kuentz. "Polyelectrolytes in Hot Melt Extrusion: A Combined Solvent-Based and Interacting Additive Technique for Solid Dispersions". Pharmaceutics 11, n.º 4 (10 de abril de 2019): 174. http://dx.doi.org/10.3390/pharmaceutics11040174.
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Solid dispersions are important supersaturating formulations to orally deliver poorly water-soluble drugs. A most important process technique is hot melt extrusion but process requirements limit the choice of suitable polymers. One way around this limitation is to synthesize new polymers. However, their disadvantage is that they require toxicological qualification and present regulatory hurdles for their market authorization. Therefore, this study follows an alternative approach, where new polymeric matrices are created by combining a known polymer, small molecular additives, and an initial solvent-based process step. The polyelectrolyte, carboxymethylcellulose sodium (NaCMC), was tested in combination with different additives such as amino acids, meglumine, trometamol, and urea. It was possible to obtain a new polyelectrolyte matrix that was viable for manufacturing by hot melt extrusion. The amount of additives had to be carefully tuned to obtain an amorphous polymer matrix. This was achieved by probing the matrix using several analytical techniques, such as Fourier transform infrared spectroscopy, differential scanning calorimetry, hot stage microscopy, and X-ray powder diffraction. Next, the obtained matrices had to be examined to ensure the homogeneous distribution of the components and the possible residual crystallinity. As this analysis requires probing a sample on several points and relies on high quality data, X-ray diffraction and starring techniques at a synchrotron source had to be used. Particularly promising with NaCMC was the addition of lysine as well as meglumine. Further research is needed to harness the novel matrix with drugs in amorphous formulations.
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Fritz, Consuelo y Juan Francisco Olivera. "Nanocellulose in Heterogeneous Water-Based Polymerization for Wood Adhesives". Polysaccharides 3, n.º 1 (15 de febrero de 2022): 219–35. http://dx.doi.org/10.3390/polysaccharides3010012.
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The interest in the development of biobased adhesives has increased due to environmental concerns. Moreover, as the production of engineered wood products (EWPs) is expected to grow, the wood adhesives market needs to transit toward formaldehyde-free products. Cellulose nanoparticles (CNPs) are a material with unique properties and advantages for producing hybrid materials as biobased wood adhesives. Besides their traditional use as reinforcing additives, CNPs can be incorporated at the beginning of the polymerization reaction to form in situ polymerized hybrid adhesives with better mechanical and physicochemical properties than the neat adhesive. Despite their outstanding characteristics, CNPs are still an emerging nanomaterial in the wood adhesive field, and the studies are incipient. This review explores the utilization of CNPs in heterogeneous polymerization for the production of polyvinyl acetate, polymeric isocyanates, waterborne polyurethane systems, and other waterborne polymer latexes. The main challenges are discussed, and some recommendations are set down for the manufacture of these novel hybrid nanocomposites.
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El-Tabei, A. S., A. E. El-Tabey y E. A. El-Sharaky. "Novel synthesized polymeric surfactants additives based on phenethylamine as an emulsion breaker for water droplet coalescence in naturally Egyptian crude oil emulsion". Journal of Molecular Liquids 338 (septiembre de 2021): 116779. http://dx.doi.org/10.1016/j.molliq.2021.116779.
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Gan, Jin Yee, Woon Chan Chong, Lan Ching Sim, Chai Hoon Koo, Yean Ling Pang, Ebrahim Mahmoudi y Abdul Wahab Mohammad. "Novel Carbon Quantum Dots/Silver Blended Polysulfone Membrane with Improved Properties and Enhanced Performance in Tartrazine Dye Removal". Membranes 10, n.º 8 (3 de agosto de 2020): 175. http://dx.doi.org/10.3390/membranes10080175.
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This study produced a novel polysulfone (PSF) membrane for dye removal using lemon-derived carbon quantum dots-grafted silver nanoparticles (Ag/CQDs) as membrane nanofiller. The preparation of CQDs was completed by undergoing hydrothermal treatment to carbonize the pulp-free lemon juice into CQD solution. The CQD solution was then coupled with Ag nanoparticles to form Ag/CQDs nanohybrid. The synthesized powders were characterized in terms of morphologies, functional groups and surface charges. A set of membranes was fabricated with different loadings of Ag/CQDs powder using the nonsolvent-induced phase separation (NIPS) method. The modified membranes were studied in terms of morphology, elemental composition, hydrophilicity and pore size. In addition, pure water flux, rejection test and fouling analysis of the membranes were evaluated using tartrazine dye. From the results, 0.5 wt % of Ag/CQD was identified as the optimum loading to be incorporated with the pristine PSF membrane. The modified membrane exhibited an excellent pure water permeability and dye rejection with improvements of 169% and 92%, respectively. In addition, the composite membrane also experienced lower flux decline, higher reversible fouling and lower irreversible fouling. This study has proven that the addition of CQD additives into membrane greatly improves the polymeric membrane’s properties and filtration performance.
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Manu, Bodhi R., Anju Gupta y Ahalapitiya H. Jayatissa. "Tribological Properties of 2D Materials and Composites—A Review of Recent Advances". Materials 14, n.º 7 (26 de marzo de 2021): 1630. http://dx.doi.org/10.3390/ma14071630.
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This paper aims to provide a theoretical and experimental understanding of the importance of novel 2D materials in solid-film lubrication, along with modulating strategies adopted so far to improve their performance for spacecraft and industrial applications. The mechanisms and the underlying physics of 2D materials are reviewed with experimental results. This paper covers some of the widely investigated solid lubricants such as MoS2, graphene, and boron compounds, namely h-BN and boric acid. Solid lubricants such as black phosphorus that have gained research prominence are also discussed regarding their application as additives in polymeric materials. The effects of process conditions, film deposition parameters, and dopants concentration on friction and wear rate are discussed with a qualitative and quantitative emphasis that are supported with adequate examples and application areas and summarized in the form of graphs and tables for easy readability. The use of advanced manufacturing methods such as powder metallurgy and sintering to produce solid lubricants of superior tribological performance and the subsequent economic gain from their development as a substitute for liquid lubricant are also evaluated.
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Avila, Luisa Bataglin, Elis Regina Correa Barreto, Caroline Costa Moraes, Marcilio Machado Morais y Gabriela Silveira da Rosa. "Promising New Material for Food Packaging: An Active and Intelligent Carrageenan Film with Natural Jaboticaba Additive". Foods 11, n.º 6 (9 de marzo de 2022): 792. http://dx.doi.org/10.3390/foods11060792.
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This research focused on the development of active and intelligent films based on a carrageenan biopolymer incorporated with jaboticaba peels extract (JPE). The bioactive extract was obtained by maceration extraction and showed high concentrations of total phenolic content (TP), total anthocyanin (TA), cyanidin-3-glucoside (Cn-3-Glu), antioxidant activity (AA), and microbial inhibition (MI) against E. coli, being promising for use as a natural additive in food packaging. The carrageenan films were produced using the casting technique, incorporating different concentrations of JPE, and characterized. The results of the thickness and Young’s modulus of the film increased in the films supplemented with JPE and the addition of the extract showed a decrease in elongation capacity and tensile strength, in water vapor permeability, and a lower rate of swelling in the water. In addition, the incorporation of JPE into the polymeric matrix promotes a change in the color of the films when compared to the control film and improves the opacity property. This is a positive effect as the material has a UV-vis light barrier which is interesting for food packaging. The increase in the active potential of the films was directly proportional to the concentration of JPE. The films results showed visible changes from purple to brown when in contact with different pH, which means that films have an intelligent potential. Accordingly, this novel carrageenan based-film incorporated with JPE could be a great strategy to add natural additives into packaging material to obtain an active potential and also an indicator for monitoring food in intelligent packaging.
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Benini, Kelly Cristina Coelho de Carvalho, Anne Shayene Campos de Bomfim y Herman Jacobus Cornelis Voorwald. "Cellulose-Reinforced Polylactic Acid Composites for Three-Dimensional Printing Using Polyethylene Glycol as an Additive: A Comprehensive Review". Polymers 15, n.º 19 (30 de septiembre de 2023): 3960. http://dx.doi.org/10.3390/polym15193960.
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Growing concerns about environmental issues and global warming have garnered increased attention in recent decades. Consequently, the use of materials sourced from renewable and biodegradable origins, produced sustainably, has piqued the interest of scientific researchers. Biodegradable and naturally derived polymers, such as cellulose and polylactic acid (PLA), have consistently been the focus of scientific investigation. The objective is to develop novel materials that could potentially replace conventional petroleum-based polymers, offering specific properties tailored for diverse applications while upholding principles of sustainability and technology as well as economic viability. Against this backdrop, the aim of this review is to provide a comprehensive overview of recent advancements in research concerning the use of polylactic acid (PLA) and the incorporation of cellulose as a reinforcing agent within this polymeric matrix, alongside the application of 3D printing technology. Additionally, a pivotal additive in the combination of PLA and cellulose, polyethylene glycol (PEG), is explored. A systematic review of the existing literature related to the combination of these materials (PLA, cellulose, and PEG) and 3D printing was conducted using the Web of Science and Scopus databases. The outcomes of this search are presented through a comparative analysis of diverse studies, encompassing aspects such as the scale and cellulose amount added into the PLA matrix, modifications applied to cellulose surfaces, the incorporation of additives or compatibilizing agents, variations in molecular weight and in the quantity of PEG introduced into the PLA/cellulose (nano)composites, and the resulting impact of these variables on the properties of these materials.
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Sharma, Shubham, P. Sudhakara, Jujhar Singh, Sanjay M. R. y S. Siengchin. "Fabrication of Novel Polymer Composites from Leather Waste Fibers and Recycled Poly(Ethylene-Vinyl-Acetate) for Value-Added Products". Sustainability 15, n.º 5 (28 de febrero de 2023): 4333. http://dx.doi.org/10.3390/su15054333.
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This investigation was focused on evaluating the utilization of Leather-waste, i.e., “Leather Shavings”, to develop “Poly(ethylene-vinyl-acetate)” (EVA) based “polymer matrix composites”. Composites with the highest ratio of 1:1 were developed using a rolling-mill, which was then subjected to hot-press molding for value-added applications, notably in the “floor-covering”, “structural”, “footwear”, and “transportation domain”. The specimens were examined for evaluating the “physico-mechanical characteristics” such as, “Compressive and Tensile, strength, Abrasion-resistance, Density, tear-resistance, hardness, adhesion-strength, compression, and resilience, damping, and water absorption” as per standard advanced testing techniques. Raising the leather-fiber fraction in the composites culminated in considerable enhancement in “physico-mechanical characteristics” including “modulus”, and a decline in “tensile-strain” at “fracture-breakage”. The thermo-analytic methods, viz. TGA and DSC studies have evidenced that substantial enhancement of thermo-stability (up to 211.1–213.81 °C) has been observed in the newly developed PMCs. Additionally, the DSC study showed that solid leather fibers lose water at an endothermic transition temperature of around 100 °C, are thermo-stable at around 211 degrees centigrade, and begin to degrade at 332.56-degree centigrade for neat recycled EVA samples and begin to degrade collagen at 318.47-degree centigrade for “leather shavings/recycled EVA polymer composite samples”, respectively. Additionally, the “glass transition temperature” (Tg) of the manufactured composites was determined to be between −16 and 30 °C. Furthermore, SEM and EDAX analysis have been used to investigate the morphological characteristics of the developed composites. Micrograph outcomes have confirmed the excellent “uniformity, compatibility, stability and better-bonding” of leather-fibers within the base matrix. Additionally, the “Attenuated-total-reflection” (ATR-FTIR) was carried out to test the “physicochemical chemical-bonding”, “molecular-structure”, and “functional-groups” of the “base matrix”, and its “composites” further affirm the “recycled EVA matrix” contained additives remain within the polymeric-matrix. An “X-ray diffraction study” was also conducted to identify the “chemical-constituents” or “phases” involved throughout the “crystal-structures” of the base matrix and PMCs. Additionally, AFM analysis has also been utilized to explore the “interfacial adhesion properties” of mechanically tested specimens of fabricated polymeric composite surfaces, their “surface topography mapping”, and “phase-imaging analysis” of polymer composites that have leather-shavings fibers.
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O’Harra, Kathryn E., Emily M. DeVriese, Erika M. Turflinger, Danielle M. Noll y Jason E. Bara. "Design and Gas Separation Performance of Imidazolium Poly(ILs) Containing Multivalent Imidazolium Fillers and Crosslinking Agents". Polymers 13, n.º 9 (24 de abril de 2021): 1388. http://dx.doi.org/10.3390/polym13091388.
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This work introduces a series of vinyl-imidazolium-based polyelectrolyte composites, which were structurally modified via impregnation with multivalent imidazolium-benzene ionic liquids (ILs) or crosslinked with novel cationic crosslinkers which possess internal imidazolium cations and vinylimidazolium cations at the periphery. A set of eight [C4vim][Tf2N]-based membranes were prepared via UV-initiated free radical polymerization, including four composites containing di-, tri-, tetra-, and hexa-imidazolium benzene ILs and four crosslinked derivatives which utilized tri- and tetra- vinylimidazolium benzene crosslinking agents. Structural and functional characterizations were performed, and pure gas permeation data were collected to better understand the effects of “free” ILs dispersed in the polymeric matrix versus integrated ionic crosslinks on the transport behaviors of these thin films. These imidazolium PIL:IL composites exhibited moderately high CO2 permeabilities (~20–40 Barrer), a 4–7× increase relative to corresponding neat PIL, with excellent selectivities against N2 or CH4. The addition of imidazolium-benzene fillers with increased imidazolium content were shown to correspondingly enhance CO2 solubility (di- < tri- < tetra- < hexa-), with the [C4vim][Tf2N]: [Hexa(Im+)Benz ][Tf2N] composite showing the highest CO2 permeability (PCO2 = 38.4 Barrer), while maintaining modest selectivities (αCO2/CH4 = 20.2, αCO2/N2 = 23.6). Additionally, these metrics were similarly improved with the integration of more ionic content bonded to the polymeric matrix; increased PCO2 with increased wt% of the tri- and tetra-vinylimidazolium benzene crosslinking agent was observed. This study demonstrates the intriguing interactions and effects of ionic additives or crosslinkers within a PIL matrix, revealing the potential for the tuning of the properties and transport behaviors of ionic polymers using ionic liquid-inspired small molecules.
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Chen, Li, Mingliang Wu, Guangwei Shao, Jiahua Hu, Guiying He, Tongle Bu, Jian-Peng Yi y Jianlong Xia. "A helical perylene diimide-based acceptor for non-fullerene organic solar cells: synthesis, morphology and exciton dynamics". Royal Society Open Science 5, n.º 5 (mayo de 2018): 172041. http://dx.doi.org/10.1098/rsos.172041.
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Helical perylene diimide-based (hPDI) acceptors have been established as one of the most promising candidates for non-fullerene organic solar cells (OSCs). In this work, we report a novel hPDI-based molecule, hPDI 2 -CN 2 , as an electron acceptor for OSCs. Combining the hPDI 2 -CN 2 with a low-bandgap polymeric donor (PTB7-Th), the blending film morphology exhibited high sensitivity to various treatments (such as thermal annealing and addition of solvent additives), as evidenced by atomic force microscope studies. The power conversion efficiency (PCE) was improved from 1.42% (as-cast device) to 2.76% after thermal annealing, and a PCE of 3.25% was achieved by further addition of 1,8-diiodooctane (DIO). Femtosecond transient absorption (TA) spectroscopy studies revealed that the improved thin-film morphology was highly beneficial for the charge carrier transport and collection. And a combination of fast exciton diffusion rate and the lowest recombination rate contributed to the best performance of the DIO-treated device. This result further suggests that the molecular conformation needs to be taken into account in the design of perylene diimide-based acceptors for OSCs.
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Lima, Guilherme M. R. y Ranjita K. Bose. "Production and Application of Polymer Foams Employing Supercritical Carbon Dioxide". Advances in Polymer Technology 2022 (28 de diciembre de 2022): 1–23. http://dx.doi.org/10.1155/2022/8905115.
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Polymeric foams have characteristics that make them attractive for different applications. However, some foaming methods rely on chemicals that are not environmentally friendly. One of the possibilities to tackle the environmental issue is to utilize supercritical carbon dioxide ScCO2 since it is a “green” solvent, thus facilitating a sustainable method of producing foams. ScCO2 is nontoxic, chemically inert, and soluble in molten plastic. It can act as a plasticizer, decreasing the viscosity of polymers according to temperature and pressure. Most foam processes can benefit from ScCO2 since the methods rely on nucleation, growth, and expansion mechanisms. Process considerations such as pretreatment, temperature, pressure, pressure drop, and diffusion time are relevant parameters for foaming. Other variables such as additives, fillers, and chain extenders also play a role in the foaming process. This review highlights the morphology, performance, and features of the foam produced with ScCO2, considering relevant aspects of replacing or introducing a novel foam. Recent findings related to foaming assisted by ScCO2 and how processing parameters influence the foam product are addressed. In addition, we discuss possible applications where foams have significant benefits. This review shows the recent progress and possibilities of ScCO2 in processing polymer foams.
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Suffo, Miguel, Celia Pérez-Muñoz, Gonzalo Alba y María Pilar Villar. "An Innovative Polypropylene/Waste Cork Composite Material for Spirit and Wine Stopper Caps". Applied Sciences 14, n.º 7 (3 de abril de 2024): 3014. http://dx.doi.org/10.3390/app14073014.
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In the wine bottling process, thermoplastics are commonly used to manufacture the crown of cork stoppers. The production of agglomerated cork stoppers generates a type of waste called cork powder (CoP) in large volumes with known properties but which are still underutilized. At present, although there are many agrocomposites available with additives such as natural fibers or solid residues from agricultural products, there are no studies describing the formation of these agrocomposites from petroleum-derived synthetic plastics combined with cork dust as a reinforcement for the polymeric matrix. The present study describes a novel agrocomposite, which has been obtained by mixing polypropylene-type materials, as they are some of the most widely used and versatile thermoplastics, with cork dust, which is a waste product obtained from the cork industry. The composite is obtained directly, without the need for grafting, adhesive polymers, or coupling agents. A superior mechanical performance compared to the unprocessed polymer was highlighted in the test results, thus evidencing the reinforcing function played by the waste in the polymer matrix. Therefore, this novel agrocomposite could be a promising alternative to replace some petroleum-derived synthetic plastics, which are currently experiencing high demand. The use of this new agrocomposite is well aligned with sustainability strategies, the principles of the circular economy, and oriented towards the fulfilment of the Sustainable Development Goals required by the European Union, considering that it contributes (a) to recycling agricultural waste that would otherwise be difficult to recover and valorize; (b) to the reduction in the CO2 footprint; and (c) to promoting the use of high-quality secondary raw materials.
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Blatman, Eyal. "NPA Cells in the Marine Environment". E3S Web of Conferences 368 (2023): 03006. http://dx.doi.org/10.1051/e3sconf/202336803006.
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Novel Polymeric Alloy (NPA) cells are a cellular confinement system with the engineering properties required by international standards for long-term confinement in demanding infrastructure projects. Three-dimensional NPA cells are used as a cover protection system against channel, stream and shoreline erosion caused by flowing water and tractive forces. NPA cells enhance the performance of conventional erosion control materials and dissipate energy from flood, current and wave action for hydraulic and marine structures and are a best available technique for canals, channels, drainage, shorelines, riverbanks, sea-walls, dams and port infrastructure. Soft or hard armor is used to optimize the erosion protection for natural or man-made channels, hydraulic structures and barriers. The surface treatment is dependent upon the geometry, hydraulic, site and environmental conditions along the water course, as well as optimization and cost-efficiencies. For example, sand infill is used for beachfront erosion control, vegetation for riverbank protection, gravel in sites subject to moderate flow velocities and concrete hard-armor in high velocity channels and walls subject to wave action. Reinforcement of load support structures in port applications can use sand, granular or recycled materials. Whereas the suitability of a cellular confinement system is directly dependent on the key attributes of the cell as well as its geometry, cells made of Novel Polymeric Alloy (NPA) have measurable higher tensile strength, resistance to deformation and environmental durability to hydraulic forces and thermal cycling over the project lifespan than conventional HDPE-based soft-cells. This includes high resistance to photochemical degradation – leaching of additives, oxidation and UV light – to preserve confinement for the lifespan of the project. Concrete solutions in non-erodible canals and walls are particularly advantageous with NPA cells. While the cellular mattress eliminates form work for fast construction, NPA cells add high tensile strength to the concrete. The creates a strong yet flexible mattress, which absorbs hydraulic forces and ground movement and resists cracking of the concrete for improved surface durability. Additionally, the high reinforcement factor of the NPA system also enables a reduction in concrete thickness to improve cost-effectiveness and sustainability. These properties also make NPA cells suitable to load support pavements used in marine ports, wharfs, terminals and container yards situated on soft, compressible and saturated soils, using sand for structural infill with no loss in structural stability.
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Wang, Zhongyi, Jinsheng Sun, Kun Zhang, Kaihe Lv, Xianbin Huang, Jintang Wang, Ren Wang y Xu Meng. "A Temperature-Sensitive Polymeric Rheology Modifier Used in Water-Based Drilling Fluid for Deepwater Drilling". Gels 8, n.º 6 (30 de mayo de 2022): 338. http://dx.doi.org/10.3390/gels8060338.
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Rheology modifiers are essential for the flat rheology of water-based drilling fluids in deepwater. The low temperature thickening of deepwater water-based drilling fluids results in dramatic rheological changes in the 20–30 °C range. To address such problems, NIPAM with a self-polymerized product LCST of 32–35 °C was selected as the main body for synthesis. While introducing the hydrophilic monomer AM to enhance the thickening properties, the hydrophobic monomer BA was selected to reduce the LCST of the product. In this paper, a temperature-sensitive polymeric rheology modifier (PNBAM) was synthesized by emulsion polymerization using N-isopropyl acrylamide, acrylamide, and butyl acrylate as monomers. The PNBAM was characterized using infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), and nuclear magnetic resonance hydrogen spectroscopy (NMR). The rheological properties, temperature resistance, and salt resistance of PNBAM in the base fluid (BF) were tested. The performance of PNBAM in the drilling fluid system was also evaluated, and a water-based drilling fluid system of flat rheology for deepwater was formulated. The rheological modification mechanism of PNBAM was analyzed by turbidity analysis, particle size analysis, and zeta analysis. Experimental results show that PNBAM has good rheological properties. PNBAM is temperature resistant to 150 °C, salt-resistant to 30 wt%, and calcium resistant to 1.0 wt%. PNBAM also has good flat rheology characteristics in drilling fluid systems: AV4°C:AV25°C = 1.27, PV4°C:PV25°C = 1.19. Mechanistic analysis showed that the LCST (Lower Critical Solution Temperature) of 0.2 wt% PNBAM in an aqueous solution was 31 °C. Through changes in hydrogen bonding forces with water, PNBAM can regulate its hydrophilic and hydrophobic properties before and after LCST, which thus assists BF to achieve a flat rheological effect. In summary, the temperature-sensitive effect of PNBAM has the property of enhancing with increasing temperature. While the tackifying effect of conventional rheology modifiers diminishes with increasing temperature, the temperature-sensitive effect of PNBAM gives it an enhanced thickening effect with increasing temperature, making it a more novel rheology modifier compared to conventional treatment additives. After LCST, compared to conventional rheology modifiers (XC), PNBAM has a more pronounced thermo-thickening effect, improving the main rheological parameters of BF by more than 100% or even up to 200% (XC less than 50%). This contributes to the flat rheology of drilling fluids. PNBAM has good application prospects and serves as a good reference for the development of other rheology modifiers.
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Najjar, Ahmad, Souhir Sabri, Rashad Al-Gaashani, Muataz Ali Atieh y Viktor Kochkodan. "Antibiofouling Performance by Polyethersulfone Membranes Cast with Oxidized Multiwalled Carbon Nanotubes and Arabic Gum". Membranes 9, n.º 2 (22 de febrero de 2019): 32. http://dx.doi.org/10.3390/membranes9020032.
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Despite extensive research efforts focusing on tackling membrane biofouling, one of the biggest problems associated with membrane technology, there has been little headway in this area. This study presents novel polyethersulfone (PES) membranes synthesized via a phase inversion method at incremental loadings of functionalized oxidized multiwalled carbon nanotubes (OMWCNT) along with 1 wt. % arabic gum (AG). The synthesized OMWCNT were examined using scanning electron microscopy and transmission electron microscopy for morphological changes compared to the commercially obtained carbon nanotubes. Additionally energy-dispersive X-ray spectroscopy was carried out on the raw and OMWCNT materials, indicating an almost 2-fold increase in oxygen content in the latter sample. The cast PES/OMWCNT membranes were extensively characterized, and underwent a series of performance testing using bovine serum albumin solution for fouling tests and model Gram-positive (Bacillus subtilis) and Gram-negative (Escherichia coli) bacterial species for anti-biofouling experiments. Results indicated that the composite PES membranes, which incorporated the OMWCNT and AG, possessed significantly stronger hydrophilicity and negative surface charge as evidenced by water contact angle and zeta potential data, respectively, when compared to plain PES membranes. Furthermore atomic force microscopy analysis showed that the PES/OMWCNT membranes exhibited significantly lower surface roughness values. Together, these membrane surface features were held responsible for the anti-adhesive nature of the hybrid membranes seen during biofouling tests. Importantly, the prepared membranes were able to inhibit bacterial colonization upon incubation with both Gram-positive and Gram-negative bacterial suspensions. The PES/OMWCNT membranes also presented more resilient normalized flux values when compared to neat PES and commercial membrane samples during filtration of both bacterial suspensions and real treated sewage effluents. Taken together, the results of this study allude to OMWCNT and AG as promising additives, for incorporation into polymeric membranes to enhance biofouling resistance.
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Al-Masoud, May Ahmed, Mai M. Khalaf, Mohamed Gouda, Van-Duong Dao, Ibrahim M. A. Mohamed, Kamal Shalabi y Hany M. Abd El-Lateef. "Synthesis and Characterization of the Mixed Metal Oxide of ZnO-TiO2 Decorated by Polyaniline as a Protective Film for Acidic Steel Corrosion: Experimental, and Computational Inspections". Materials 15, n.º 21 (28 de octubre de 2022): 7589. http://dx.doi.org/10.3390/ma15217589.
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In this work, the preparation, characterization, and evaluation of a novel nanocomposite using polyaniline (PANi) functionalized bi-metal oxide ZnO-TiO2 (ZnTiO@PANi) as shielding film for carbon steel (CS)-alloy in acidic chloride solution at 298 K was studied. Different spectroscopic characterization techniques, such as UV-visible spectroscopy, dynamic light scattering (DLS), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectroscopy (FTIR) approaches, as well as other physicochemical methods, such as X-ray diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), and field emission scanning electron microscope (FESEM), were used to describe the produced nanocomposites. The significance of these films lies in the ZnO-TiO2 nanoparticle’s functionalization by polyaniline, a material with high conductivity and electrochemical stability in acidic solutions. The mechanistic findings of the corrosion inhibition method were obtained by the use of electrochemical methods including open-circuit potentials (OCP) vs. time, potentiodynamic polarization (PDP), and electrochemical impedance spectroscopy (EIS). The results indicate that the synthesized ZnTiO@PANi is a powerful acidic corrosion inhibitor, and its inhibition effectiveness is 98.86% in the presence of 100 ppm. Additionally, the charge transfer resistance (Rp) value augmented from 51.8 to 432.7, and 963.7 Ω cm2 when the dose of PANi, and ZnTiO@PANi reached 100 ppm, respectively. The improvement in Rp and inhibition capacity values with an increase in nanocomposite dose is produced by the nanocomposite additives covering a larger portion of the surface, resulting in a decrease in alloy corrosion. By identifying the probable regions for molecule adsorption on the steel substrate, theoretical and computational studies provided significant details regarding the corrosion mitigation mechanism. The possibility of substituting old poisonous small substances with inexpensive and non-hazardous polymeric materials as shielding layers for utilization in the oilfield sectors is an important suggestion made by this research.
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Malara, Angela, Lucio Bonaccorsi, Antonio Fotia, Pier Luigi Antonucci y Patrizia Frontera. "Hybrid Fluoro-Based Polymers/Graphite Foil for H2/Natural Gas Separation". Materials 16, n.º 5 (5 de marzo de 2023): 2105. http://dx.doi.org/10.3390/ma16052105.
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Membrane technologies and materials development appear crucial for the hydrogen/natural gas separation in the impending transition to the hydrogen economy. Transporting hydrogen through the existing natural gas network could result less expensive than a brand-new pipe system. Currently, many studies are focused on the development of novel structured materials for gas separation applications, including the combination of various kind of additives in polymeric matrix. Numerous gas pairs have been investigated and the gas transport mechanism in those membranes has been elucidated. However, the selective separation of high purity hydrogen from hydrogen/methane mixtures is still a big challenge and nowadays needs a great improvement to promote the transition towards more sustainable energy source. In this context, because of their remarkable properties, fluoro-based polymers, such as PVDF-HFP and NafionTM, are among the most popular membrane materials, even if a further optimization is needed. In this study, hybrid polymer-based membranes were deposited as thin films on large graphite surfaces. Different weight ratios of PVDF-HFP and NafionTM polymers supported over 200 μm thick graphite foils were tested toward hydrogen/methane gas mixture separation. Small punch tests were carried out to study the membrane mechanical behaviour, reproducing the testing conditions. Finally, the permeability and the gas separation activity of hydrogen/methane over membranes were investigated at room temperature (25 °C) and near atmospheric pressure (using a pressure difference of 1.5 bar). The best performance of the developed membranes was registered when the 4:1 polymer PVDF-HFP/NafionTM weight ratio was used. In particular, starting from the 1:1 hydrogen/methane gas mixture, a 32.6% (v%) H2 enrichment was measured. Furthermore, there was a good agreement between the experimental and theoretical selectivity values.
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Goodwin, Sophie R., Amy Stimpson, Richard Moon, Lauren Cowie, Najib Aragrag, Sorin V. Filip, Andrew G. Smith y Derek J. Irvine. "Facile Synthesis of Functionalised Hyperbranched Polymers for Application as Novel, Low Viscosity Lubricant Formulation Components". Polymers 14, n.º 18 (14 de septiembre de 2022): 3841. http://dx.doi.org/10.3390/polym14183841.
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A novel, previously unreported, method for synthesising hyperbranched (HB) materials is detailed. Their use as additives to produce lubricant formulations that exhibit enhanced levels of wear protection and improved low-temperature oil viscosity and flow is also reported. The lubricant formulations containing HB additives were found to exhibit both significantly lower viscosities and improved in-use film-forming properties than the current industry standard formulations. To achieve this, alkyl methacrylate oligomers (predominantly dimers and trimers) were synthesised using catalytic chain transfer polymerisation. These were then used as functional chain transfer agents (CTA) to control the polymerisation of divinyl benzene (DVB) monomers to generate highly soluble, high polydispersity HB polymers. The level of dimer/trimer purification applied was varied to define its influence on both these HB resultant structures and the resultant HB additives’ performance as a lubricant additive. It was shown that, while the DVB acted as the backbone of the HB, the base oil solubility of the additive was imparted by the presence of the alkyl chains included in the structure via the use of the oligomeric CTAs.
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Kato, Ken, Hirofumi Mukai, Taito Esaki, Shozo Ohsumi y Yasuo Hozumi. "Phase I clinical study of NK105, paclitaxel-encapsulating micelles, on a weekly schedule, in patients with malignant tumors (dose-escalation phase)." Journal of Clinical Oncology 31, n.º 15_suppl (20 de mayo de 2013): 3082. http://dx.doi.org/10.1200/jco.2013.31.15_suppl.3082.
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3082 Background: NK105 is the formulation of a novel drug delivery system that encapsulates paclitaxel (PTX) in polymeric micelles and possibly resolves the safety issues associated with the additives contained in the conventional PTX formulation. In the phase II study of NK105 administered to gastric cancer patients on a 150Emg/m2 triweekly schedule, peripheral sensory neuropathy was mitigated compared to prior data for conventional PTX, without any reduction in efficacy. Based on the dose-density theory, we conducted a phase I study of NK105 on a weekly schedule to determine the dose-limiting toxicity (DLT) and recommended dosage (RD), and to evaluate the pharmacokinetic profile. Methods: Patients with advanced solid tumors refractory to standard therapy received NK105 at dosage levels of 50-100 mg/m2 as a 30-min infusion without premedication, once a week for three weeks, followed by one week of rest. Pharmacokinetic analysis was conducted in cycles 1 and 2. Results: Sixteen patients were enrolled in the study. In the 100Emg/m2 cohort (n=7), one patient experienced DLT (grade 4 neutropenia lasting 5 days), and dose reduction or delay was necessary in 4 of the 7 patients during the first course due to neutropenia. It was decided that 100 mg/m2 was the maximum tolerated dosage, and the RD was set at 80 mg/m2. Grade 3 or more severe adverse drug reactions reported for the 80Emg/m2 cohort were neutropenia, anemia, fatigue, hearing impaired and ataxia. Comparison of the pharmacokinetic parameters of NK105 with those of PTX at the same dosage (100 mg/m2) showed that the AUC0-inf. and Vdss of NK105 were approximately 50-fold and 1/15 of the reported PTX values, respectively. A refractory gastric cancer patient and an esophageal cancer patient each showed a partial response, at dosages of 80 mg/m2 and 100 mg/m2, respectively. Conclusions: 80Emg/m2 weekly administration of NK105 was well tolerated and showed anti-tumor activity, including partial responses and several occurrences of stable disease. The expansion phase of the study is ongoing at the RD of 80 mg/m2. Clinical trial information: JapicCTI-101233.
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Carpenter, Chris. "Polyaramide Vesicles Prove Effective for Wellbore Integrity and CO2 Sequestration". Journal of Petroleum Technology 74, n.º 01 (1 de enero de 2022): 87–89. http://dx.doi.org/10.2118/0122-0087-jpt.
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This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 204385, “Wellbore Integrity and CO2 Sequestration Using Polyaramide Vesicles,” by Elizabeth Q. Contreras, SPE, Saudi Aramco. The paper has not been peer reviewed. The complete paper describes a cementing additive chemically engineered to react with formation fluids that act antagonistically toward cement. Engineered polymer capsules house encapsulants to react with antagonistic gases downhole, such as carbon dioxide (CO2), to form a more benign and beneficial material. Embedded in cement, the polymer capsules with semipermeable shells allow fluids to permeate and react with encapsulants to produce beneficial byproducts, such as calcite and water from CO2. Reactivity between the encapsulant and antagonist gas CO2 is demonstrated using thermal gravimetric analysis (TGA) and other tests from oilfield equipment. Cementing Applications for Polyaramide Vesicles The study presents the third and final technology for polyaramide vesicles, a novel polymeric material for cement enhancement and for multifaceted cement applications. In oil and gas wells, polyaramide vesicles have applications as a cement additive with delivery capabilities. This family of polymers also is chemically inert and stable enough to serve in various applications under extreme downhole conditions during the construction of an oil well. When incorporated into cement, the high thermomechanical stability of these vesicles serves to enhance mechanical properties of Portland cement such as elasticity while maintaining the full strength of the cement. The unique vesicular design of the polymer also serves as a delivery system for relevant cement additives and is applied in the development of right-angle-set cements. Thereafter, the robustness of the shell remains intact after chemical delivery to impart strength and flexibility to set cement for the lifetime of the well. In this study, the vesicles housing reagents are used for the sequestration of antagonistic gases, to neutralize and to produce mineral precipitate for the applicatory repairs of microannuli in the cement sheath, and for self-healing cements. During the construction process, a good cement job serves the purpose of providing a reliable infrastructure during production and for zonal isolation of the casing string from subterranean environments. Zonal isolation by cementing is important to prevent the loss of hydrocarbons during production and to prevent the influx of unwanted formation fluids into the wellbore, such as sweet and sour gases. Maintaining cement-sheath integrity helps keep the production of hydrocarbons cost-efficient and safe. However, numerous factors may cause cement to fail. Oil and gas wells generally go through stress and thermal cycles during production. Changes in downhole conditions, in terms of temperature and pressure, can induce enough destructive stress to affect the integrity of the cement sheath. Any producing oil and gas well can suffer sudden thermomechanical fatigue failure, leading to microannuli and fractures in cement sheaths. Elastomeric materials such as polyaramide vesicles can be added to make cement less brittle and reduce the development of microannuli. However, in the event of gas migration by casing/casing annulus (CCA) events, mitigation requires a solution for complete remediation and recovery of the well.
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Fahad, M., P. Dickens y M. Gilbert. "Novel polymeric support materials for jetting based additive manufacturing processes". Rapid Prototyping Journal 19, n.º 4 (7 de junio de 2013): 230–39. http://dx.doi.org/10.1108/13552541311323245.
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Latos-Brozio, Malgorzata, Anna Masek y Małgorzata Piotrowska. "Novel Polymeric Biomaterial Based on Naringenin". Materials 14, n.º 9 (23 de abril de 2021): 2142. http://dx.doi.org/10.3390/ma14092142.
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Biomaterials prepared based on raw plant materials are becoming more and more popular due to their specific properties and environmental friendliness. Naringenin is a flavonoid naturally occurring in citrus fruit with antioxidant and pharmacological activity. Polymeric materials based on flavonoids may have favorable properties in comparison to monomeric polyphenols, such as stronger antioxidant and antimicrobial properties. One of the methods of obtaining the polymeric form of flavonoids is polymerization with a cross-linking compound. This method has already been used to obtain poly(quercetin) and poly(rutin) from a flavonol group as well as poly(catechin) from the flavan-3-ol group of flavonoids. However, to date, no polymeric forms of flavanones have been prepared in a cross-linking reaction; the aim of this study was to obtain poly(naringenin) by reaction with a cross-linking compound using glycerol diglycide ether GDE. The degree of conversion of naringenin to poly(naringenin) determined by FTIR spectroscopy was 85%. In addition, the thermal, antioxidant and antimicrobial properties of poly(naringenin) were analyzed. Poly(naringenin) was characterized by greater resistance to oxidation and better thermal stability than monomeric naringenin. Moreover, polymeric naringenin also had a better ability to scavenge ABTS and DPPH free-radicals. In contrast to monomeric form, poly(naringenin) had antimicrobial activity against Candida albicans. Polymeric biomaterial based on naringenin could potentially be used as a natural stabilizer and antimicrobial additive for polymer compositions, as well as pro-ecological materials.
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Li, Ao, Dezhong Xu, Mengnan Zhang, Shengzhong Wu, Yu Li, Weisheng Sun, Yonghui Zhou, Omar Abo Madyan, Mizi Fan y Jiuping Rao. "Grafting nanocellulose with diethylenetriaminepentaacetic acid and chitosan as additive for enhancing recycled OCC pulp fibres". Cellulose 29, n.º 3 (10 de enero de 2022): 2017–32. http://dx.doi.org/10.1007/s10570-021-04390-9.
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AbstractThis paper develops a novel paper additive for effectively recycling old corrugated container (OCC) by functionalizing nanocellulose (NC) with diethylenetriaminepentaacetic acid (DTPA) and chitosan (CS), and investigate the reinforcing mechanisms and effect of the developed additive on the physical properties of recycled OCC pulp handsheets. The tensile, tear and burst index, air permeability, tensile energy absorption (TEA), and drainage performance of the recycled OCC handsheets are examined. Fourier transform infrared FTIR) spectroscopy, thermal gravimetric analysis (TGA) and scanning electron microscopy (SEM) are used for the chemical and microstructure characterization of both NC based additives and paper from recycled OCC pulp. The results show that functional groups on the NC based additive, such as carboxyl, amino and hydroxyl groups, can bond with the hydroxyl groups on the recycled OCC fibres to generate a chemical bond. This leads to an increase in the crosslinks and bonding area between the fibres, which increases their tensile strength and improves their recycling rate. SEM shows that the paper with NC based additives had tighter inter-fibre bonds and smaller paper pore structure. Addition of 0.3% NC-DTPA-CS additive results in optimal properties of the recycled OCC paper with an increase by 31.64%, 22.28% and 36.6% of tensile index, tear index, burst index respectively, and the air permeability decreases by 36.92%. Graphical Abstract