Journal articles: 'Inorganic Oxide-Polymer Composites'

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Rahman, Mohammad Mizanur. "Polyurethane/Zinc Oxide (PU/ZnO) Composite—Synthesis, Protective Property and Application." Polymers 12, no. 7 (July 11, 2020): 1535. http://dx.doi.org/10.3390/polym12071535.

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A polyurethane (PU) is a multifunctional polymer prepared by using more than two types of monomers. The unique properties of PU come from monomers, thus broadening the applicability of PU in many different sectors. The properties can be further improved by using many nanoparticles. Different metal oxides as nanoparticles are also widely used in PU materials. ZnO is a widely used inorganic metal oxide nanoparticle for improving polymer properties. In this review article, the techniques to prepare a PU/ZnO composite are reviewed; the key protective properties, such as adhesive strength and self-healing, and applications of PU/ZnO composites are also highlighted. This review also highlights the PU/ZnO composite’s current challenges and future prospects, which will help to broaden the composite practical application by preparing environmentally friendly composites.

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Vázquez-López, Antonio, Marina García-Carrión, Erlend Hall, Anisa Yaseen, Ilknur Kalafat, María Taeño, Junjie Zhu, et al. "Hybrid Materials and Nanoparticles for Hybrid Silicon Solar Cells and Li-Ion Batteries." Journal of Energy and Power Technology 03, no. 02 (November 9, 2020): 1. http://dx.doi.org/10.21926/jept.2102020.

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Hybrid composites based on inorganic nanomaterials embedded into a polymer matrix have were synthesized and characterized. Oxide semiconductor nanoparticles (SnO, SnO2, TiO2, Ga2O3, and NiO) and Si nanoparticles were employed as inorganic counterparts in the hybrid composite, while a conductive polymer (PEDOT:PSS) with diverse additives was used as the organic matrix. The composites were spin-coated on Si or glass substrates. The potential use of these materials in photovoltaic devices to improve Si surface passivation behavior was investigated. Besides, the use of the nanoparticles as active materials for anodes in Li-ion batteries was evaluated. Some other aspects, such as the durability and stability of these materials, were also assessed.

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Zharkova, G. M., K. V. Zobov, N. A. Romanov, V. V. Syzrantsev, and S. P. Bardakhanov. "Polymer-liquid crystal composites doped by inorganic oxide nanopowders." Nanotechnologies in Russia 10, no. 5-6 (May 2015): 380–87. http://dx.doi.org/10.1134/s1995078015030210.

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Prathap, Murali, Kulasekaran Poonkuzhali, Maria Mahimai Berlina, Pushparaj Hemalatha, and Deivanayagam Paradesi. "Synthesis and characterization of sulfonated poly(ether ether ketone)/zinc cobalt oxide composite membranes for fuel cell applications." High Performance Polymers 32, no. 9 (May 5, 2020): 984–91. http://dx.doi.org/10.1177/0954008320922296.

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A new series of polymer composite membranes was fabricated using a linear sulfonated poly(ether ether ketone) (SPEEK) polymer with zinc cobalt oxide (ZCO) as an inorganic filler and evaluated for fuel cell applications. SPEEK was obtained by the direct sulfonation of PEEK using concentrated sulfuric acid, and appropriate quantities of ZCO were loaded into it to yield the polymer composites. Proton nuclear magnetic resonance studies revealed the degree of sulfonation of SPEEK to be 55%, while morphological studies confirmed the successful incorporation of inorganic fillers into the polymer matrix. To evaluate the suitability of the prepared composite membranes for fuel cell applications, their physicochemical properties were studied in detail. The pristine SPEEK membrane exhibited a proton conductivity of 0.009 S cm−1 at 30°C, whereas the values for the composite membranes loaded with 2.5 to 10 wt% of ZCO were in the range 0.012–0.020 S cm−1. Moreover, the composite membranes showed excellent thermal stability up to 370°C. Indeed, the membranes obtained by the incorporation of ZCO into the SPEEK polymer show potential for fuel cell applications.

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Fallah, Mahroo, Kenneth J. D. MacKenzie, John V. Hanna, and Samuel J. Page. "Novel photoactive inorganic polymer composites of inorganic polymers with copper(I) oxide nanoparticles." Journal of Materials Science 50, no. 22 (July 29, 2015): 7374–83. http://dx.doi.org/10.1007/s10853-015-9295-3.

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Xie, Jiliang. "Application of Graphene Oxide–Natural Polymer Composite Adsorption Materials in Water Treatment." Symmetry 15, no. 9 (August 31, 2023): 1678. http://dx.doi.org/10.3390/sym15091678.

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Graphene is a new type of carbon material with excellent properties that has been developed in recent years. Graphene composites have potential application value in solving the problem of water pollution. In this study, we investigated the properties and performance of graphene composites prepared through polymer modification and inorganic particle doping modification. Our research focused on the composites’ ability to adsorb heavy metal ions and degrade organic compounds through photocatalysis. In this study, we prepared graphene oxide (GO) first and then grafted p-phenylenediamine onto its surface. The process was successful and yielded promising results. The aniline grafted onto the graphene oxide surface was used as anchor point for the in situ redox polymerization of aniline, and a polyaniline macromolecular chain was grafted onto the edge of graphene oxide. The structure of the composite was determined using Fourier transform infrared spectroscopy, thermogravimetry, X-ray diffraction, and Raman spectroscopy and transmission electron microscopy. The adsorption performance of Pb+ on GO-PANI composite was studied. The maximum adsorption capacity of the GO-PANI composite for Pb+ is 1416 mg/g, 2.3 times that of PANI. Graphene/polyaniline composites can be used as an excellent adsorbent for Pb2+ heavy metal ions and have great application prospects in heavy metal wastewater treatment.

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Danchenko, Yuliya, Vladimir Andronov, Tatyana Obizhenko, Anatoliy Kosse, and Igor Khmyrov. "The Influence of Inorganic Fillers on the Protective Properties of Epoxy Polymer Composite Materials." International Journal of Engineering & Technology 7, no. 4.3 (September 15, 2018): 279. http://dx.doi.org/10.14419/ijet.v7i4.3.19804.

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The influence of regularities of the chemical-mineralogical nature, the dispersity, and the surface properties of inorganic fillers on the protective properties of epoxy polymer composite materials have been investigated. Polymeric compositions based on epoxy resin of ED-20 brand and aliphatic amine curing agent of diethylenetriamine of DETA brand have been chosen as the research materials. The fillers were the air-dry dispersed materials of different nature: oxide, clay and quartz. The resistance of the composites to water and aqueous solutions (absorbency) was investigated by dipping the samples into an aggressive aqueous medium. For the received samples of the filled composites, thermogravimetric (TG) and differential scanning calorimetry (DSC) method were used using the SDT Q600 device manufactured by TA Instruments (USA). It has been found that the thermal stability and the absorbing capacity of the filled composites in water and aqueous acidic and alkaline mediums correlate with each other. It has been shown that to obtain materials with improved protective characteristics, it is necessary to use oxide or clay fillers with the basic (alkaline) surface function.

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Korzekwa, Joanna, Elżbieta Bociąga, and Dariusz Bochenek. "Investigation of Selected Polymer Composite-Aluminum Oxide Coating Tribological Systems." Materials 13, no. 23 (December 2, 2020): 5491. http://dx.doi.org/10.3390/ma13235491.

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The tribotesting of friction systems requires discussion on proper selection of its conditions and data presentation. System tribology is based, for example, on analysis of the friction contact, the roughness of the cooperating surfaces, and the wear rate of the rubbing elements or coefficient of friction in relation to the sliding distance. Friction pairs, consisting of an aluminum alloy sample with an oxide layer (Al2O3) with and without the addition of inorganic fullerenes like tungsten disulphide (IF-WS2) nanoparticles on its surface cooperating with a counter-sample made of polymer composites prepared on the basis of phenol-formaldehyde resin with different fillers, were tested using a device with a pin-on-plate friction pair system. The results of the experiments showed sufficient durability of the Al2O3 and Al2O3/IF-WS2 oxide coatings in combination with the polymer composite. It was found that resin fillers such as cotton fibers, jute fibers, molybdenum disulphide (MoS2) or graphite (C) influence the friction behavior of the tribological pairs. Although the values of the coefficient of friction obtained in the tests were quite high, their course during the tests ensured stable cooperation of the aluminum coating/polymer composite friction pair on a 15 km distance, under a load of 0.5 MPa. The lowest coefficients of friction were obtained for oxide layers formed on aluminum combined with a polymer composite filled with cotton fibers and graphite. These studies provide information on the tribological properties of commercially available polymer composites cooperating with the produced oxide coatings, supplementing the available literature with the results of research on new, so far unexplored tribological partners. Microscopic investigation of the structure and morphology of the formed surface oxide layers and also microgeometry studies of both the friction elements were used to better understand the obtained research results.

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Berman, Diana, Yuchen Sha, and Elena V. Shevchenko. "Effect of Polymer Removal on the Morphology and Phase of the Nanoparticles in All-Inorganic Heterostructures Synthesized via Two-Step Polymer Infiltration." Molecules 26, no. 3 (January 28, 2021): 679. http://dx.doi.org/10.3390/molecules26030679.

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Polymer templates play an essential role in the robust infiltration-based synthesis of functional multicomponent heterostructures with controlled structure, porosity, and composition. Such heterostructures are be used as hybrid organic–inorganic composites or as all-inorganic systems once the polymer templates are removed. Using iron oxide/alumina heterostructures formed by two-step infiltration of polystyrene-block-polyvinyl pyridine block copolymer with iron and aluminum precursors from the solution and vapor-phases, respectively, we show that the phase and morphology of iron oxide nanoparticles dramatically depend on the approach used to remove the polymer. We demonstrate that thermal and plasma oxidative treatments result in iron oxide nanoparticles with either solid or hollow morphologies, respectively, that lead to different magnetic properties of the resulting materials. Our study extends the boundaries of structure manipulations in multicomponent heterostructures synthesized using polymer infiltration synthesis, and hence their properties.

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Ahadzade, Sh M., I. A. Vakulenko, and Kh Asgarov. "Factors Influence on Electrophysical Parameters of the Composite Varistors." Science and Transport Progress, no. 1(101) (March 14, 2023): 29–36. http://dx.doi.org/10.15802/stp2023/283013.

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Purpose. Evaluation influence structural state polymer phase on the response voltage and coefficient nonlinearity of a multilayer varistor based on zinc oxide. Methodology. Zinc oxide consisted of 97% zinc oxide and 3% total oxides of Bi2O3, Co3O4, MnO2, B2O3, SbO3, ZrO2, Al2O3. At a temperature of 1573°K, the synthesis of semiconductor ceramics based on Zinc oxide was carried out. For composite of thermoplastic polymers and Zinc oxide, non-polar and polar polymers, high pressure polyethylene and polyvinylidene fluoride were used. The composites were obtained by hot pressing at the melting temperature of the polymer phase and a pressure of 15 MPa. After that, using silver paste, measuring electrodes 10 mm in diameter were applied to the surface of the synthesized samples, and then current–voltage characteristics were measured. Modification of composites under action of gas-discharge plasma was carried out in a special cell that creates a dielectric-gas-composite system. The structure of the composites was studied by X-ray diffraction analysis and IR spectroscopy. Findings. The obtained experimental results show that the size of the particles of the inorganic phase significantly affects the current-voltage characteristics of the composite varistor: at a given thickness of the composite varistor, the operation voltage decreases markedly, and the nonlinearity coefficient increases. Numerous experimental results obtained by us show that the impact of electric discharge plasma on the polymer Zinc oxide-composite leads to a significant change in the permittivity and the concentration of local levels at the interface of the composite. The results research showed that effect electrical plasma on the opening voltage depends on the polarity of polymer matrices. Moreover, plasma processing itself significantly changes the structure of the polymer phase at composite. Originality. The magnitude of the potential barrier at phase boundary is mainly determined by the volume fraction and size of the main structural element of ZnO ceramics. Changing the structural state of the polymer matrix allows the adjust response voltage and coefficient nonlinearity of volt-ampere characteristic of the multilayer varistor. Practical value. The discovered development of electron-ion processes at polymer phase of the varistor indicates the need to take into account change in its service characteristics from the duration and intensity of use. The result obtained has a certain practical significance, since it indicates not only the reason for the change in properties, but also the need to develop measures to increase the service life of the varistor.

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Borshchov, V. M., O. M. Listratenko, M. A. Protsenko, I. T. Tymchuk, O. V. Kravchenko, O. V. Syddia, M. I. Slipchenko, and B. M. Chichkov. "Dispersion of nanoparticles in optically transparent polymer matrices." Radiotekhnika, no. 204 (April 9, 2021): 105–14. http://dx.doi.org/10.30837/rt.2021.1.204.12.

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Search and analysis of results of theoretical and experimental studies, materials of dissertations, literature sources and patents in the field of optical and optoelectronic instrumentation were carried out. Obtained data and recommendations on the development of methods for dispersing nanoparticles into polymer matrices for the creation of optically transparent nan composites for use in many fields of science and technology are generalized. Analysis of considered results makes it possible to conclude that for creating hybrid organic-inorganic composites with high level of dispersion of inorganic component, it is necessary to solve problems relating to compatibility of components and stabilization of filler nanoparticles in polymer matrix. Due to the limited range of hydrophilic polymers capable of forming composites with nanoparticles without stabilizers, the main approaches to the preparation of hybrid composites are using modifying additives of surfactants, as well as complex chemical reactions on the surface of inorganic filler nanoparticles. Such methods of obtaining nanocomposites with nanoparticles are laborious and involve formation of by-products and additional purification. It is shown that titanium dioxide (TiO2) and zinc oxide (ZnO) are of great interest among a large number of nanodispersed fillers of polymer matrices in preparing composite materials. There are many methods for synthesis of ZnO and TiO2 nanoparticles with various shapes and sizes, including laser ablation method, which is convenient and universal method for preparing nanosuspensions of solid-phase materials in liquid. Advantages over other methods for nanoparticle synthesis, such as the simplicity of method, environmental friendliness, low cost, and the ability to obtain cleaner colloidal solutions without using surfactants and other impurities, have made laser ablation in a liquid medium very popular among researchers.

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Kuklin, Vladimir, Sergey Karandashov, Elena Bobina, Sergey Drobyshev, Anna Smirnova, Oleg Morozov, and Maxim Danilaev. "Analysis of Aluminum Oxides Submicron Particle Agglomeration in Polymethyl Methacrylate Composites." International Journal of Molecular Sciences 24, no. 3 (January 28, 2023): 2515. http://dx.doi.org/10.3390/ijms24032515.

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Agglomeration of distributed particles is the main problem in polymer composites reinforced with such particles. It leads to a decrease in mechanical performance and its poor reproducibility. Thus, development of methods to address the agglomeration of particles is relevant. Evaluation of the size and concentration of agglomerates is required to select a method to address agglomeration. The paper analyzes aluminum oxide particles agglomeration in particles-reinforced polymethyl methacrylate (PMMA) composites. Quantitative parameters of polystyrene-coated aluminum oxide particles agglomerates are obtained for the first time in this article. Unlike uncoated aluminum oxide particles, when coated aluminum oxide particles are used, agglomerates concentration in polymer composites decreases approx. 10 times. It demonstrates that modification of submicron particles by a polymer coating decreases the number of agglomerates in the polymer composite. The use of transmittance and opacity values to estimate particles agglomerates is reasonable in this article. It is shown that the difference in optical performance of specimens reinforced with coated and the original particles is related to the number and average size of agglomerates in the specimens. For example, when the concentration exceeds 0.2%, transmittance values for the specimens reinforced with coated particles are greater than the ones for the specimens reinforced with the original particles.

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Hyvärinen, Marko, Svetlana Butylina, and Timo Kärki. "Accelerated and Natural Weathering of Wood-Polypropylene Composites Containing Pigments." Advanced Materials Research 1077 (December 2014): 139–45. http://dx.doi.org/10.4028/www.scientific.net/amr.1077.139.

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In general, wood-polymer composites are vulnerable to weathering factors such as UV radiation, moisture, freeze-thaw action. Weathering can cause discoloration, chalking, dimensional change, and loss of mechanical properties of wood-polymer composites. This comparative study was focused on weatherability of wood–polypropylene composites made with and without pigments. Two types of inorganic pigments were applied: carbon black master-batch and synthetic iron oxide. Wood-polypropylene composite made without pigment was used as a reference. Also, composites prepared with addition of wollastonite were tested. The composite samples were exposed to outdoor weathering and in a parallel the accelerated UV weathering was conducted in xenon weathering chamber for the 2000 hours. The colour change was estimated by spectrophotometric method, and the change of Charpy impact strength after weathering was determined. The surface morphology was studied with scanning electron microscopy (SEM). The addition of pigments decreased the lightness of non-weathered composites. The change of lightness and total colour change of weathered composites were affected a lot by type of pigment and method of weathering. As, expected wood-polypropylene composite made with carbon black showed the best results in colour stability of composites exposed to weathering. SEM showed that accelerated weathering in the xenon chamber caused more significant changes in the morphology of the polymer surface layer of the composites than outdoor weathering. Charpy impact strength of all studied composites was found to retain after 2000 hours of outdoor weathering, although accelerated weathering caused significant reduction of Charpy impact strength of these composites.

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Egorin, Andrei, Eduard Tokar, Anna Matskevich, Nikita Ivanov, Ivan Tkachenko, Tatiana Sokolnitskaya, and Larisa Zemskova. "Composite Magnetic Sorbents Based on Iron Oxides in Different Polymer Matrices: Comparison and Application for Removal of Strontium." Biomimetics 5, no. 2 (May 18, 2020): 22. http://dx.doi.org/10.3390/biomimetics5020022.

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Introduction of magnetic nanoparticles into composite sorbents based on polymer matrices has received great attention due to the possibility of using cheap iron oxides and removing spent sorbents by means of magnetic separation. In the present paper, we discuss the problem of creating magnetic sorbents using two types of matrices as host materials: synthetic cation exchange resin and natural aminopolysaccharide chitosan. The possibilities of applying matrices for the in situ formation of oxide phases of a specified composition with the required content of an inorganic component in a composite material were estimated. The composition of the oxide phase formed in the composite material was studied, and particle sizes were evaluated by the method of X-ray diffraction analysis. Magnetic characteristics were investigated. Sorption characteristics with respect to strontium for the composites containing iron oxides were determined.

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Zemskova, Larisa, Andrei Egorin, Eduard Tokar, Vladimir Ivanov, and Svetlana Bratskaya. "New Chitosan/Iron Oxide Composites: Fabrication and Application for Removal of Sr2+ Radionuclide from Aqueous Solutions." Biomimetics 3, no. 4 (December 4, 2018): 39. http://dx.doi.org/10.3390/biomimetics3040039.

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Here, we discuss the fabrication and problems of application of chitosan-based composite materials for the removal of hazardous metal ions from tap water and wastewater. The chitosan-based composites containing iron oxides for the uptake of Sr2+ ions were fabricated via a co-precipitation method with variation of the iron/chitosan ratio and pH of the medium. The morphology and composition of the fabricated sorbents were characterized using scanning electron microscopy–energy dispersive X-ray spectroscopy (SEM–EDX) and X-ray diffraction (XRD) analysis. We have shown that the suggested fabrication approach allows for a homogeneous distribution of the inorganic phase in the polymer matrix. Investigations of the sorption performance of the composites have shown that they are efficient sorbents for 90Sr radionuclides uptake from tap water. The composite sorbent containing amorphous iron oxide in a chitosan matrix and calcined at 105 °C showed the best sorption characteristics. We have also demonstrated that there is an optimal iron oxide content in the composite: with increasing oxide content, the efficiency of the sorbents decreases due to poor stability in solution, especially in alkaline media. The alternative approach yielding magnetic chitosan-based composites with sufficiently good sorption performance and stability in neutral and weakly alkaline media is suggested.

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Dhapte, Vividha, Shivajirao Kadam, Varsha Pokharkar, Pawan K. Khanna, and Vishwas Dhapte. "Versatile SiO2 Nanoparticles@Polymer Composites with Pragmatic Properties." ISRN Inorganic Chemistry 2014 (January 29, 2014): 1–8. http://dx.doi.org/10.1155/2014/170919.

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In the present work, we report the fabrication of silica nanoparticles embedded polymeric (SiO2 nanoparticles@polymer) composite films for numerous traits like texture, folding endurance, crystallinity, size, thermal behavior, spectral analysis, and bioactivity. Significant facets of bulky, inert, inorganic materials are known to burgeon out due to the high surface area of nanosized particles. Nature and proportion of silica nanoparticles as well as polymers exhibited remarkable impact on the fabrication and quality of casted films. Hydrophilic silica nanoparticulate-PVA films depicted better mechanical properties like thermal plus photo stability. Hydrophobic silica nanoparticulate-PMMA films showed qualities of a robust, active, thermostable, antimicrobial material that could resist extreme storage and processing conditions. Overall, these metal oxide nanoparticle-polymer composite films possess qualities reflecting their potential in food, pharmaceutical, and cosmetic industry.

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Wood, Nathan D., Lisa J. Gillie, David J. Cooke, and Marco Molinari. "A Review of Key Properties of Thermoelectric Composites of Polymers and Inorganic Materials." Materials 15, no. 23 (December 5, 2022): 8672. http://dx.doi.org/10.3390/ma15238672.

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This review focusses on the development of thermoelectric composites made of oxide or conventional inorganic materials, and polymers, with specific emphasis on those containing oxides. Discussion of the current state-of-the-art thermoelectric materials, including the individual constituent materials, i.e., conventional materials, oxides and polymers, is firstly presented to provide the reader with a comparison of the top-performing thermoelectric materials. Then, individual materials used in the inorganic/polymer composites are discussed to provide a comparison of the performance of the composites themselves. Finally, the addition of carbon-based compounds is discussed as a route to improving the thermoelectric performance. For each topic discussed, key thermoelectric properties are tabulated and comparative figures are presented for a wide array of materials.

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Barra, Ana, Cláudia Nunes, Eduardo Ruiz-Hitzky, and Paula Ferreira. "Green Carbon Nanostructures for Functional Composite Materials." International Journal of Molecular Sciences 23, no. 3 (February 6, 2022): 1848. http://dx.doi.org/10.3390/ijms23031848.

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Carbon nanostructures are widely used as fillers to tailor the mechanical, thermal, barrier, and electrical properties of polymeric matrices employed for a wide range of applications. Reduced graphene oxide (rGO), a carbon nanostructure from the graphene derivatives family, has been incorporated in composite materials due to its remarkable electrical conductivity, mechanical strength capacity, and low cost. Graphene oxide (GO) is typically synthesized by the improved Hummers’ method and then chemically reduced to obtain rGO. However, the chemical reduction commonly uses toxic reducing agents, such as hydrazine, being environmentally unfriendly and limiting the final application of composites. Therefore, green chemical reducing agents and synthesis methods of carbon nanostructures should be employed. This paper reviews the state of the art regarding the green chemical reduction of graphene oxide reported in the last 3 years. Moreover, alternative graphitic nanostructures, such as carbons derived from biomass and carbon nanostructures supported on clays, are pointed as eco-friendly and sustainable carbonaceous additives to engineering polymer properties in composites. Finally, the application of these carbon nanostructures in polymer composites is briefly overviewed.

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Huang, Yu-Chao, Pei-Wen Lin, Wen-Jian Qiu, and Ta-I. Yang. "AMPHIPHILIC POLYMER-ASSISTED SYNTHESIS OF HYDROXYAPATITE PARTICLES AND THEIR INFLUENCE ON THE RHEOLOGICAL AND MECHANICAL PROPERTIES OF THERMOSENSITIVE HYDROGELS." Biomedical Engineering: Applications, Basis and Communications 28, no. 02 (April 2016): 1650013. http://dx.doi.org/10.4015/s1016237216500137.

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Polymeric composite materials hold promise for versatile advanced applications. Of utmost importance for these applications is incorporating inorganic particles within polymer matrices which lead to multifunctional polymeric composites with desired functions. Specifically, thermosensitive polymeric hydrogels incorporating particle fillers have elicited widespread interest because of promising applications in drug delivery, tissue engineering, and medical devices. Although these materials are frequently discussed in many research fields, there are no decisive conclusions reported in literature, showing how the particle filler affects the rheological and mechanical behaviors of the resulting hydrogels. In this research, hydroxyapatite (HAp) bioceramics with definable morphologies were synthesized in order to reveal their effects on the resulting properties of HAp/polymer composite hydrogels. HAp particles with spherical, sheet-like and rod-like shapes were prepared with assistance by adding amphiphilic surfactant, poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide) in synthesis. Thermosensitive composite hydrogels with controllable rheological and mechanical properties were thus developed by incorporating HAp particles into poly(ethylene glycol)-b-poly(lactide-co-glycolide) (PEG-PLGA) hydrogel. Experimental results revealed that the rheological and mechanical properties of the resultant HAp/PEG-PLGA composite hydrogel not only influenced by the added HAp particle amount, but also by the particle morphology and interactions between particles and hydrogels. The findings from this research provide a critical guideline for designing thermosensitive composite hydrogels with required rheological and mechanical properties.

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Jinga, Sorin-Ion, Claudiu-Constantin Costea, Andreea-Ioana Zamfirescu, Adela Banciu, Daniel-Dumitru Banciu, and Cristina Busuioc. "Composite Fiber Networks Based on Polycaprolactone and Bioactive Glass-Ceramics for Tissue Engineering Applications." Polymers 12, no. 8 (August 12, 2020): 1806. http://dx.doi.org/10.3390/polym12081806.

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In this work, composite fibers connected in three-dimensional porous scaffolds were fabricated by electrospinning, starting from polycaprolactone and inorganic powders synthesized by the sol-gel method. The aim was to obtain materials dedicated to the field of bone regeneration, with controllable properties of bioresorbability and bioactivity. The employed powders were nanometric and of a glass-ceramic type, a fact that constitutes the premise of a potential attachment to living tissue in the physiological environment. The morphological characterization performed on the composite materials validated both the fibrous character and oxide powder distribution within the polymer matrix. Regarding the biological evaluation, the period of immersion in simulated body fluid led to the initiation of polymer degradation and a slight mineralization of the embedded particles, while the osteoblast cells cultured in the presence of these scaffolds revealed a spatial distribution at different depths and a primary networking tendency, based on the composites’ geometrical and dimensional features.

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Vlăsceanu, George Mihail, Mariana Ioniță, Corina Cristiana Popescu, Elena Diana Giol, Irina Ionescu, Andrei-Mihai Dumitrașcu, Mădălina Floarea, et al. "Chitosan-Based Materials Featuring Multiscale Anisotropy for Wider Tissue Engineering Applications." International Journal of Molecular Sciences 23, no. 10 (May 10, 2022): 5336. http://dx.doi.org/10.3390/ijms23105336.

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We designed graphene oxide composites with increased morphological and structural variability using fatty acid-coupled polysaccharide co-polymer as the continuous phase. The matrix was synthesized by N, O-acylation of chitosan with palmitic and lauric acid. The obtained co-polymer was crosslinked with genipin and composited with graphene oxide. FTIR spectra highlighted the modification and multi-components interaction. DLS, SEM, and contact angle tests demonstrated that the conjugation of hydrophobic molecules to chitosan increased surface roughness and hydrophilicity, since it triggered a core-shell macromolecular structuration. Nanoindentation revealed a notable durotaxis gradient due to chitosan/fatty acid self-organization and graphene sheet embedment. The composited building blocks with graphene oxide were more stable during in vitro enzymatic degradation tests and swelled less. In vitro viability, cytotoxicity, and inflammatory response tests yielded promising results, and the protein adsorption test demonstrated potential antifouling efficacy. The robust and stable substrates with heterogeneous architecture we developed show promise in biomedical applications.

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Noworyta, Małgorzata, Monika Topa-Skwarczyńska, Paweł Jamróz, Dawid Oksiuta, Małgorzata Tyszka-Czochara, Klaudia Trembecka-Wójciga, and Joanna Ortyl. "Influence of the Type of Nanofillers on the Properties of Composites Used in Dentistry and 3D Printing." International Journal of Molecular Sciences 24, no. 13 (June 23, 2023): 10549. http://dx.doi.org/10.3390/ijms241310549.

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Photopolymerization is a growing field with an extensive range of applications and is environmentally friendly owing to its energy-efficient nature. Such light-assisted curing methods were initially used to cure the coatings. However, it has become common to use photopolymerization to produce 3D objects, such as bridges or dental crowns, as well as to cure dental fillings. In this study, polymer nanocomposites containing inorganic nanofillers (such as zinc nano-oxide and zinc nano-oxide doped with two wt.% aluminum, titanium nano-oxide, kaolin nanoclay, zirconium nano-oxide, aluminum nano-oxide, and silicon nano-oxide) were fabricated and studied using Real Time FT-IR to investigate the effects of these nanoadditives on the final conversion rates of the obtained nanocomposites. The effects of the fillers on the viscosity of the produced nanocomposites were also investigated, and 3D prints of the selected nanocomposites were presented.

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Rybiński, Przemysław, Bartłomiej Syrek, Dariusz Bradło, Witold Żukowski, Rafał Anyszka, and Mateusz Imiela. "Influence of cenospheric fillers on the thermal properties, ceramisation and flammability of nitrile rubber composites." Journal of Composite Materials 52, no. 20 (February 9, 2018): 2815–27. http://dx.doi.org/10.1177/0021998318754996.

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In this paper, the influence of cenospheric fillers of different particle sizes on the thermal properties and flammability of butadiene-acrylonitrile rubber is presented. A part of fly ash cenospheres was coated with an iron and iron (III) oxide layer. A series of examinations were conducted, these took the forms of: thermal analysis; oxygen index analysis; cone calorimeter measurements; SEM; AFM. These examinations enabled the explanation of iron-based combustion inhibition processes in terms of catalysis of char formation and elastomer cross-linking. Cenospheres itself without additional coatings or fillers provide high surface for polymer chain adsorption, and hence degradation of composite is reduced. Additionally, the results of the investigation on the effectiveness of cenospheric filler usage for ceramisation are discussed. It is proven that the durable ceramic structure is formed owing to the addition of cenospheres in the presence of an inorganic flux. Thus, replacement of silica by lightweight cenospheres is possible. Cenospheres with an iron coating and in the presence of wollastonite and an inorganic flux allow obtaining the NBR composites which are non-flammable in the air atmosphere; furthermore, the ceramic layer formed during the composite combustion has advantageous mechanical properties.

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Boyano, Iker, Aroa R. Mainar, J. Alberto Blázquez, Andriy Kvasha, Miguel Bengoechea, Iratxe de Meatza, Susana García-Martín, Alejandro Varez, Jesus Sanz, and Flaviano García-Alvarado. "Reduction of Grain Boundary Resistance of La0.5Li0.5TiO3 by the Addition of Organic Polymers." Nanomaterials 11, no. 1 (December 29, 2020): 61. http://dx.doi.org/10.3390/nano11010061.

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The organic solvents that are widely used as electrolytes in lithium ion batteries present safety challenges due to their volatile and flammable nature. The replacement of liquid organic electrolytes by non-volatile and intrinsically safe ceramic solid electrolytes is an effective approach to address the safety issue. However, the high total resistance (bulk and grain boundary) of such compounds, especially at low temperatures, makes those solid electrolyte systems unpractical for many applications where high power and low temperature performance are required. The addition of small quantities of a polymer is an efficient and low cost approach to reduce the grain boundary resistance of inorganic solid electrolytes. Therefore, in this work, we study the ionic conductivity of different composites based on non-sintered lithium lanthanum titanium oxide (La0.5Li0.5TiO3) as inorganic ceramic material and organic polymers with different characteristics, added in low percentage (<15 wt.%). The proposed cheap composite solid electrolytes double the ionic conductivity of the less cost-effective sintered La0.5Li0.5TiO3.

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Jinga, Zamfirescu, Voicu, Enculescu, Evanghelidis, and Busuioc. "PCL-ZnO/TiO2/HAp Electrospun Composite Fibers with Applications in Tissue Engineering." Polymers 11, no. 11 (November 1, 2019): 1793. http://dx.doi.org/10.3390/polym11111793.

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The main objective of the tissue engineering field is to regenerate the damaged parts of the body by developing biological substitutes that maintain, restore, or improve original tissue function. In this context, by using the electrospinning technique, composite scaffolds based on polycaprolactone (PCL) and inorganic powders were successfully obtained, namely: zinc oxide (ZnO), titanium dioxide (TiO2) and hydroxyapatite (HAp). The novelty of this approach consists in the production of fibrous membranes based on a biodegradable polymer and loaded with different types of mineral powders, each of them having a particular function in the resulting composite. Subsequently, the precursor powders and the resulting composite materials were characterized by the structural and morphological point of view in order to determine their applicability in the field of bone regeneration. The biological assays demonstrated that the obtained scaffolds represent support that is accepted by the cell cultures. Through simulated body fluid immersion, the biodegradability of the composites was highlighted, with fiber fragmentation and surface degradation within the testing period.

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Din, Ummi Kalsom Noor, Muhamad Mat Salleh, Tengku Hasnan Tengku Aziz, Ahmad Rifqi Md Zain, Mohd Ambri Mohamed, and Akrajas Ali Umar. "On the performance of polymer-inorganic perovskite oxide composite light-emitting diodes: The effect of perovskite SrTiO3 additives." Nanomaterials and Nanotechnology 11 (January 1, 2021): 184798042098777. http://dx.doi.org/10.1177/1847980420987774.

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This study reports the performances of a single structured light-emitting diode (LED) devices based on polymer material poly(9,9-di- n-hexylfluorenyl-2,7-diyl) (PHF) mixed with various concentrations of perovskite oxide strontium titanate (SrTiO3) particles deposited as a composite PHF: SrTiO3 emitting layer. The performances of the single structured organic LED indium tin oxide (ITO)/PHF/aluminum (Al) device and the composite LED ITO/PHF: SrTiO3/Al devices were compared in terms of turn-on voltage and luminance intensity. By incorporating perovskite SrTiO3 particles into PHF emitting layer, the turn-on voltage of the device is significantly reduced from 11.25 V to 1.80 V and the luminance intensity increased from 57.7 cd/m2 to 609 cd/m2. The improvement of turn-on voltage and the electroluminescence spectrum of the composite devices were found to be dependent on the weight ratios of SrTiO3 content in the PHF emitting layer.

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Lombardi, Mariangela, Paolo Fino, and Laura Montanaro. "Influence of ceramic particle features on the thermal behavior of PPO-matrix composites." Science and Engineering of Composite Materials 21, no. 1 (January 1, 2014): 23–28. http://dx.doi.org/10.1515/secm-2012-0139.

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AbstractThermoplastic poly(phenylene oxide) (PPO)-matrix composites were prepared and characterized in order to evaluate the effect of different ceramic fillers on the thermal and combustion behavior of the matrix. In particular, ceramic particles having three different shapes were exploited as fillers, particles showing a platelet-like, a needle-like or an equiaxial morphology. The composite materials were produced through a melt blending method, which yielded a homogeneous distribution of the ceramic particles in the organic matrix. It was demonstrated that the presence of the inorganic particles influenced the temperature range in which the degradation processes of the polymer occurred. In addition, the three fillers modified the thermal behavior of PPO differently in terms of enthalpy. Finally, the presence of the filler induced a change in combustion behavior of the polymeric matrix; in particular, sepiolite was able to increase the charring ability of the PPO/polystyrene blend with the development of a visible carbonaceous layer.

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Ayyubov, Ilgar, Adriana Vulcu, Camelia Berghian-Grosan, Emília Tálas, Irina Borbáth, István E. Sajó, György Sáfrán, Judith Mihály, and András Tompos. "Preparation of Pt electrocatalyst supported by novel, Ti(1−x)MoxO2-C type of composites containing multi-layer graphene." Reaction Kinetics, Mechanisms and Catalysis 135, no. 1 (December 22, 2021): 49–69. http://dx.doi.org/10.1007/s11144-021-02138-x.

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AbstractBall milling is a relative simple and promising technique for preparation of inorganic oxide–carbon type of composites. Novel TiO2-C and Ti0.8Mo2O2-C type of composites containing multi-layer graphene were prepared by ball milling of graphite in order to get electrocatalyst supports for polymer electrolyte membrane fuel cells. Starting rutile TiO2 was obtained from P25 by heat treatment. Carbon-free Ti0.8Mo2O2 mixed oxide, prepared using our previously developed multistep sol–gel method, does not meet the requirements for materials of electrocatalyst support, therefore parent composites with Ti0.8Mo2O2/C = 75/25, 90/10 and 95/5 mass ratio were prepared using Black Pearls 2000. XRD study of parent composites proved that the oxide part existed in rutile phase which is prerequisite of the incorporation of oxophilic metals providing CO tolerance for the electrocatalyst. Ball milling of TiO2 or parent composites with graphite resulted in catalyst supports with enhanced carbon content and with appropriate specific surface areas. XRD and Raman spectroscopic measurements indicated the changes of graphite during the ball milling procedure while the oxide part remained intact. TEM images proved that platinum existed in the form of highly dispersed nanoparticles on the surface of both the Mo-free and of Mo-containing electrocatalyst. Electrocatalytic performance of the catalysts loaded with 20 wt% Pt was studied by cyclic voltammetry, COads-stripping voltammetry done before and after the 500-cycle stability test, as well as by the long-term stability test involving 10,000 polarization cycles. Enhanced CO tolerance and slightly lower stability comparing to Pt/TiO2-C was demonstrated for Pt/Ti0.8Mo2O2-C catalysts.

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Bratskaya, Svetlana, Alexander Mironenko, Risto Koivula, Alla Synytska, Anna Musyanovych, Frank Simon, Dmitry Marinin, Michael Göbel, Risto Harjula, and Valentin Avramenko. "Polymer–Inorganic Coatings Containing Nanosized Sorbents Selective to Radionuclides. 2. Latex/Tin Oxide Composites for Cobalt Fixation." ACS Applied Materials & Interfaces 6, no. 24 (December 8, 2014): 22387–92. http://dx.doi.org/10.1021/am5064074.

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Lee, Li-Ting, Sheng-Ping He, and Chih-Feng Huang. "Enhancement of Crystallization Behaviors in Quaternary Composites Containing Biodegradable Polymer by Supramolecular Inclusion Complex." Crystals 10, no. 12 (December 12, 2020): 1137. http://dx.doi.org/10.3390/cryst10121137.

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Novel multi-component composites composed of the biodegradable polymer poly(ethylene adipate) (PEA), the water-soluble polymer poly(ethylene oxide) (PEO), poly(vinyl acetate) (PVAc), and a supramolecular-like inclusion complex (IC) made by α-cyclodextrin (α-CD) and poly(ε-caprolactone) (PCL) (coded as PCL–CD–IC) are discussed in this work. The PCL–CD–IC was used to increase the crystallization rate of the miscible PEA/PEO/PVAc ternary blend that crystalized slower than neat PEA. Higher resolution SEM and TEM images displayed that PCL–CD–IC did not assemble notably in the quaternary composites. For the results of isothermal crystallization, the analysis of the Avrami equation demonstrated that the rate constant k increased with the addition of PCL–CD–IC in the composites, suggesting that PCL–CD–IC provided more nucleation sites to promote the crystallization rate. The nucleation density increased with the addition of PCL–CD–IC, and the amount of spherulite also increased. Wide angle X-ray results showed that the composites displayed similar diffraction patterns to neat PEA, meaning PEO, PVAc, and PCL–CD–IC would not change the crystal structures of PEA in the composites. The PCL–CD–IC, the supramolecular nucleation agent, demonstrated its superior ability to enhance the multi-component composites of biodegradable polymer in this study.

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Gandhimathi, Sivasubramanian, Hariharasubramanian Krishnan, and Deivanayagam Paradesi. "Development of proton-exchange polymer nanocomposite membranes for fuel cell applications." Polymers and Polymer Composites 28, no. 7 (November 16, 2019): 492–501. http://dx.doi.org/10.1177/0967391119888319.

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The design and development of proton conducting polymer electrolyte membranes from a linear constituent, sulfonated poly (ether ether ketone) (SPEEK), and inorganic additive, niobium oxide (NBO), have been achieved. The degree of sulfonation of SPEEK was measured by back titration method and found to be 57%. The physicochemical properties such as water uptake ability, ion-exchange capacity, swelling ratio, proton conductivity, and thermal stability of the prepared polymer nanocomposite membranes were studied in detail. The distribution of NBO throughout the polymer matrix has been examined by scanning electron microscopic and X-ray diffraction analyses and found to be uniform. The SP-NBO-10 composite membrane shows 38.4% of water uptake, whereas the pristine membrane limits to 27.1%. The prepared electrolyte membranes exhibit good proton conductivity at temperature varying from 30°C to 90°C and possess less activation energy for the transportation of proton by the incorporation of NBO filler. The thermal studies demonstrated that the stability of the composite membranes was significantly enhanced by the impregnation of NBO. The filler NBO shows excellent improvements on the polymer nanocomposite, making it a very promising additive for other polymers and offers new roads for energy applications.

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32

Guo, Shuaibing, Xuexin Duan, Mengying Xie, Kean Chin Aw, and Qiannan Xue. "Composites, Fabrication and Application of Polyvinylidene Fluoride for Flexible Electromechanical Devices: A Review." Micromachines 11, no. 12 (December 3, 2020): 1076. http://dx.doi.org/10.3390/mi11121076.

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The technological development of piezoelectric materials is crucial for developing wearable and flexible electromechanical devices. There are many inorganic materials with piezoelectric effects, such as piezoelectric ceramics, aluminum nitride and zinc oxide. They all have very high piezoelectric coefficients and large piezoelectric response ranges. The characteristics of high hardness and low tenacity make inorganic piezoelectric materials unsuitable for flexible devices that require frequent bending. Polyvinylidene fluoride (PVDF) and its derivatives are the most popular materials used in flexible electromechanical devices in recent years and have high flexibility, high sensitivity, high ductility and a certain piezoelectric coefficient. Owing to increasing the piezoelectric coefficient of PVDF, researchers are committed to optimizing PVDF materials and enhancing their polarity by a series of means to further improve their mechanical–electrical conversion efficiency. This paper reviews the latest PVDF-related optimization-based materials, related processing and polarization methods and the applications of these materials in, e.g., wearable functional devices, chemical sensors, biosensors and flexible actuator devices for flexible micro-electromechanical devices. We also discuss the challenges of wearable devices based on flexible piezoelectric polymer, considering where further practical applications could be.

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Bouzat, Fabien, Romain Lucas, Yann Leconte, Sylvie Foucaud, Yves Champavier, Cristina Coelho Diogo, and Florence Babonneau. "Formation of ZrC–SiC Composites from the Molecular Scale through the Synthesis of Multielement Polymers." Materials 14, no. 14 (July 13, 2021): 3901. http://dx.doi.org/10.3390/ma14143901.

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In the field of non-oxide ceramic composites, and by using the polymer-derived ceramic route, understanding the relationship between the thermal behaviour of the preceramic polymers and their structure, leading to the mechanisms involved, is crucial. To investigate the role of Zr on the fabrication of ZrC–SiC composites, linear or hyperbranched polycarbosilanes and polyzirconocarbosilanes were synthesised through either “click-chemistry” or hydrosilylation reactions. Then, the thermal behaviours of these polymeric structures were considered, notably to understand the impact of Zr on the thermal path going to the composites. The inorganic materials were characterised by thermogravimetry-mass spectrometry (TG-MS), X-ray diffraction (XRD), and scanning electron microscopy (SEM). To link the macromolecular structure to the organisation involved during the ceramisation process, eight temperature domains were highlighted on the TG analyses, and a four-step mechanism was proposed for the polymers synthesised by a hydrosilylation reaction, as they displayed better ceramic yields. Globally, the introduction of Zr in the polymer had several effects on the temperature fragmentation mechanisms of the organometallic polymeric structures: (i) instead of stepwise mass losses, continuous fragment release prevailed; (ii) the stability of preceramic polymers was impacted, with relatively good ceramic yields; (iii) it modulated the chemical composition of the generated composites as it led, inter alia, to the consumption of free carbon.

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Sommertune, Jens, Abhilash Sugunan, Anwar Ahniyaz, Rebecca Bejhed, Anna Sarwe, Christer Johansson, Christoph Balceris, Frank Ludwig, Oliver Posth, and Andrea Fornara. "Polymer/Iron Oxide Nanoparticle Composites—A Straight Forward and Scalable Synthesis Approach." International Journal of Molecular Sciences 16, no. 8 (August 20, 2015): 19752–68. http://dx.doi.org/10.3390/ijms160819752.

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Chausson, Sophie, Richard Retoux, Jean-Michel Rueff, Loïc LE Pluart, Pierre-Jean Madec, and Paul-Alain Jaffres. "Elaboration and characterization of novel polyamide-12-layered titanoniobates nanocomposites." Journal of Materials Research 24, no. 11 (November 2009): 3358–71. http://dx.doi.org/10.1557/jmr.2009.0410.

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This article describes the synthesis and the characterization of a polyamide-12 filled with a nanostructured organic/inorganic titanoniobate hybrid material. The pristine oxide KTiNbO5 has been successfully organomodified by N-alkyl amines via an acido-basic reaction after a cationic exchange step as shown by x-ray diffraction. Transmission electron microscope study and scanning transmission electron microscope observations have been used to describe the change of morphology of the nanofillers before and after processing; the micronic aggregates were changed into single sheets and dispersed in the polymer. Thermomechanical properties of the composites have been determined, and their analyses with structure-properties models are consistent with the exfoliation of the organomodified titanoniobates.

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Krystyjan, Magdalena, Gohar Khachatryan, Karen Khachatryan, Anna Konieczna-Molenda, Anna Grzesiakowska, Marta Kuchta-Gładysz, Agnieszka Kawecka, Wiktoria Grzebieniarz, and Nikola Nowak. "The Functional and Application Possibilities of Starch/Chitosan Polymer Composites Modified by Graphene Oxide." International Journal of Molecular Sciences 23, no. 11 (May 25, 2022): 5956. http://dx.doi.org/10.3390/ijms23115956.

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This study describes functional properties of bionanocomposites consisting of starch/chitosan/graphene oxide (GO) obtained using the green synthesis method, such as water-barrier and optical properties, as well as the rate of degradation by enzymatic and acid hydrolysis. The toxicity of the composites and their effects on the development of pathogenic microflora during storage of meat food products was also investigated. Although the results showed that the barrier properties of the composites were weak, they were similar to those of biological systems. The studies carried out confirmed the good optical properties of the composites containing chitosan, which makes it possible to use them as active elements of packaging. The susceptibility of starch and chitosan films to enzymatic and acid hydrolyses indicates their relatively high biodegradability. The lack of toxicity and the high barrier against many microorganisms offer great potential for applications in the food industry.

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Chen, Hao, Guoping Zhang, Kathleen Richardson, and Jian Luo. "Synthesis of Nanostructured Nanoclay-Zirconia Multilayers: a Feasibility Study." Journal of Nanomaterials 2008 (2008): 1–8. http://dx.doi.org/10.1155/2008/749508.

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This paper reports the first effort to synthesize a new class of inorganic nanostructured materials consisting of alternating ultrathin layers of nanoclays and oxide ceramics. A novel solution-based layer-by-layer (LBL) deposition technique was developed to prepare multilayers of hydrated Zr cations and nanoclays. This LBL deposition technique is devised by integrating an electrostatic-mediated dip coating method for making nanoclay-polymer multilayers with a successive ionic layer adsorption and reaction method for making ultrathin oxide films. Nanostructured clay-zirconia multilayer composites formed through subsequent annealing. Characterization by scanning electron microscopy, energy dispersive X-ray spectroscopy, and X-ray diffraction confirmed that these films are uniform and crack-free, consist of no detectable impurities, and possess nanoscale-layered structure. The incorporation of nanoclays facilitates the electrostatic-mediated assembling of multilayers, enhances the structural integrity, and provides a generic framework to construct functionally graded materials. Potential applications are envisaged.

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Lee, Jin Hee, Yu Jung Park, Jung Hwa Seo, and Bright Walker. "Hybrid Lead-Halide Polyelectrolytes as Interfacial Electron Extraction Layers in Inverted Organic Solar Cells." Polymers 12, no. 4 (March 27, 2020): 743. http://dx.doi.org/10.3390/polym12040743.

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A series of lead-halide based hybrid polyelectrolytes was prepared and used as interfacial layers in organic solar cells (OSCs) to explore their effect on the energy band structures and performance of OSCs. Nonconjugated polyelectrolytes based on ethoxylated polyethylenimine (PEIE) complexed with PbX2 (I, Br, and Cl) were prepared as polymeric analogs of the perovskite semiconductors CH3NH3PbX3. The organic/inorganic hybrid composites were deposited onto Indium tin oxide (ITO) substrates by solution processing, and ultraviolet photoelectron spectroscopy (UPS) measurements confirmed that the polyelectrolytes allowed the work function of the substrates to be controlled. In addition, X-ray photoelectron spectroscopy (XPS) results showed that Pb(II) halide complexes were present in the thin film and that the Pb halide species did not bond covalently with the cationic polymer and confirmed the absence of additional chemical bonds. The composite ratio of organic and inorganic materials was optimized to improve the performance of OSCs. When PbBr2 was complexed with the PEIE material, the efficiency increased up to 3.567% via improvements in open circuit voltage and fill factor from the control device (0.3%). These results demonstrate that lead-halide based polyelectrolytes constitute hybrid interfacial layers which provide a novel route to control device characteristics via variation of the lead halide composition.

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Meng, Lingyao, Hongyou Fan, J. Matthew D. Lane, and Yang Qin. "Bottom-Up Approaches for Precisely Nanostructuring Hybrid Organic/Inorganic Multi-Component Composites for Organic Photovoltaics." MRS Advances 5, no. 40-41 (2020): 2055–65. http://dx.doi.org/10.1557/adv.2020.196.

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Abstract:Achieving control over the morphology of conjugated polymer (CP) blends at nanoscale is crucial for enhancing their performances in diverse organic optoelectronic devices, including thin film transistors, photovoltaics, and light emitting diodes. However, the complex CP chemical structures and intramolecular interactions often make such control difficult to implement. We demonstrate here that cooperative combination of non-covalent interactions, including hydrogen bonding, coordination interactions, and π-π interactions, etc., can be used to effectively define the morphology of CP blend films, in particular being able to achieve accurate spatial arrangement of nanoparticles within CP nanostructures. Through UV-vis absorption spectroscopy and transmission electron microscopy, we show strong attachment of fullerene molecules, CdSe quantum dots, and iron oxide nanoparticles, onto well-defined CP nanofibers. The resulting core/shell hybrid nanofibers exhibit well-defined donor/acceptor interface when employed in photovoltaic devices, which also contributes to enhanced charge separation and transport. These findings provide a facile new methodology of improving CP/nanoparticle interfacial properties and controlling blend morphology. The generality of this methodology demonstrated in current studies points to a new way of designing hybrid materials based on organic polymers and inorganic nanoparticles towards applications in modern electronic devices.

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Perlova, O. V., Yu S. Dzyazko, A. A. Malinovska, and A. V. Palchik. "Peculiarities of U(VI) sorption on composites containing hydrated titanium dioxide and potassium-cobalt hexacyanoferrate(II)." Himia, Fizika ta Tehnologia Poverhni 12, no. 4 (December 30, 2021): 344–57. http://dx.doi.org/10.15407/hftp12.04.344.

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As opposed to polymer sorbents, inorganic materials are stable against ionizing radiation. This gives a possibility to use them for the removal of radionuclides from water. As a rule, highly selective inorganic sorbents are obtained in a form of finely dispersive powder. This makes it difficult to use them in practice. Here the composites based on hydrated titanium dioxide containing K2Co[Fe(CN)6] have been developed. The modifier was inserted into partially (hydrogel) and fully (xerogel) formed oxide matrices. Modifying of hydrogel followed its transformation to xerogel provides the formation of potassium-cobalt hexacyanoferrate(II) nanoparticles (up to 10 nm), which are not washed out in aqueous media due to encapsulation in hydrated oxide. A number of the methods for sample characterization were used in this work: transmission electronic microscopy for vizualization of embedded nanoparticles, optical microscopy to measure granule size, FT-IR spectroscopy, X-ray fluorescence spectroscopy for chemical analysis of the samples, potentiometric titration to estimate ion exchange properties, and spectrophotometric analysis of the solution to determine U(VI) concentration. The features of U(VI) sorption from nitrate and sulfate solutions are considered: the effect of the sorbent dosage and solution composition was in a focus of attention. The influence of the modifier is the most pronounced at pH ³ 4, when U(VI) is in a form of one-charged cations (UO2OH+): the removal degree of U(VI) is close to 100 %. This positive effect of the selective constituent is expressed in a presence of an excess of NO3–, SO42– and Na+ ions. The model of chemical reaction of pseudo second order has been applied to sorption. Both pristine sorbent and composite are most completely regenerated with a 0.1 M KOH solution - the regeneration degree is 92 and 96 % respectively. In this case, the half-exchange time is minimal and equal to » 23 min (initial hydrated titanium dioxide) and 47 min (composite). Desorption obeys the model of particle diffusion: the diffusion coefficients for ions being exchanged are (1.7–7.6)´10–13 m2s–1.

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Schneider, Jörg J., and Meike Naumann. "Template-directed synthesis and characterization of microstructured ceramic Ce/ZrO2@SiO2 composite tubes." Beilstein Journal of Nanotechnology 5 (July 25, 2014): 1152–59. http://dx.doi.org/10.3762/bjnano.5.126.

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An exo-templating synthesis process using polymeric fibers and inorganic sol particles deposited onto structured one-dimensional objects is presented. In particular, CeO2/ZrO2@SiO2 composite tubes were synthesized in a two-step procedure by using electrospun polystyrene fibers as fiber template. First, a sol–gel approach based on an exo-templating technique was employed to obtain polystyrene(PS)/SiO2 composite fibers. These composite fibers were subsequently covered by spray-coating with ceria and zirconia sol solutions. After drying and final calcination of the green body composites, the PS polymer template was removed, and composite tubes of the composition CeO2/ZrO2@SiO2 were obtained. The SiO2/ZrO2/CeO2 microtubes, which consist of interconnected silica particles, are held together by ceria and zirconia deposits formed during the thermal treatment process. These microtubes are mainly located in the pendentive connecting the individual spherical silica particles and glue them together. The composition and crystallinity of this material connecting the individual silica particles contains the elements Ce and Zr and O as mixed oxide solid solution identified by XRD, Raman and high-resolution TEM and EFTEM. High-resolution microscopy techniques allowed for an elemental mapping on the surface of the silica host structure and determination of the O, Zr and Ce elemental distribution with nm precision.

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Stevens, J. R., and W. Wieczorek. "Ionically conducting polyether composites." Canadian Journal of Chemistry 74, no. 11 (November 1, 1996): 2106–13. http://dx.doi.org/10.1139/v96-239.

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Ionic conductivity in polymer–salt electrolytes occurs in the amorphous regions of the complex. Poly(ethylene oxide) (PEO) is the best polyether for complexing salts. Unfortunately, it is partially crystalline at ambient temperatures. With inorganic (i.e., alumina) or organic (i.e., poly(acrylamide) (PAAM)) fillers the crystallization of PEO is inhibited and the room temperature conductivity is enhanced in these mixed phase systems by over two orders of magnitude (to ~ 10−4 S/cm) above the base PEO–salt system (<10− S/cm). Even adding PAAM to an initially amorphous system (oxymethylene-linked PEO–LiClO4) increases the room temperature conductivity by 2 to 3 times. Various alkali metal salts (Li, Na) and NH4SCN are used with α-Al2O3, θ-Al2O3, PAAM′ and poly(N,N′-dimethyl acrylamide) as fillers. The aluminas stiffen the complex and increase Tg. The addition of the organic fillers lowers Tg, as is to be preferred. It is suggested that changes in the conductivity with changes in salt and filler concentration are due to changes in the ultrastructure and morphology and are the result of an equilibrium between various Lewis acid – Lewis base reactions. Qualified success has been achieved in modelling ionic conductivity in these composite electrolyte systems using an effective medium approach. In this approach it has been assumed that the main conductivity enhancement takes place in thin amorphous layers of the polyether that coat the dispersed polyacrylamide particles separated in a microphase. In the best complexes this layer is identified by a second Tg. Key words: polyethers, composites, ionic conductivity, phase structure, Lewis acids and bases.

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Chibac, Andreea Laura, Tinca Buruiana, Violeta Melinte, and Emil C. Buruiana. "Photocatalysis applications of some hybrid polymeric composites incorporating TiO2 nanoparticles and their combinations with SiO2/Fe2O3." Beilstein Journal of Nanotechnology 8 (January 27, 2017): 272–86. http://dx.doi.org/10.3762/bjnano.8.30.

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Polymer nanocomposites containing titanium oxide nanoparticles (TiO2 NPs) combined with other inorganic components (Si–O–Si or/and γ-Fe2O3) were prepared by the dispersion of premade NPs (nanocrystalline TiO2, TiO2/SiO2, TiO2/Fe2O3, TiO2/SiO2/Fe2O3) within a photopolymerizable urethane dimethacrylate (polytetrahydrofuran-urethane dimethacrylate, PTHF-UDMA). The physicochemical characterization of nanoparticles and hybrid polymeric composites with 10 wt % NPs (S1–S4) was realized through XRD, TEM and FTIR analyses. The mean size (10–30 nm) and the crystallinity of the NPs varied as a function of the inorganic constituent. The catalytic activity of these hybrid films was tested for the photodegradation of phenol, hydroquinone and dopamine in aqueous solution under UV or visible-light irradiation. The best results were obtained for the films with TiO2/Fe2O3 or TiO2/SiO2/Fe2O3 NPs. The degradation of the mentioned model pollutants varied between 71% and 100% (after 250 min of irradiation) depending on the composition of the hybrid film tested and the light applied (UV–visible light). Also, it was established that such hybrid films can be reused at least for five cycles, without losing too much of the photocatalytic efficiency (ca. 7%). These findings could have implications in the development of new nanocatalysts.

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Sahu, K. R., and Udayan De. "UHF and X Band Electro-Magnetic Shielding of Advanced Devices by Some Polymer–Composites." Material Science Research India 13, no. 2 (December 19, 2016): 80–94. http://dx.doi.org/10.13005/msri/130204.

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Electro-magnetic interference (EMI) affects delicate electronic devices and living beings. Composites of a polymeric binder with fine metallic turnings (copper and brass), powders of conducting inorganic compounds (suitably fired cadmium oxide), ferroelectric powders (BaTiO3 and orthorhombic PbNb2O6), and with their combinations have been prepared as cloth-like sheets, and characterized in a Vector Network Analyzer (VNA) with respect to EMI shielding and reflection capabilities. Input power (Pin) for the EMI shield (above-mentioned test materials), the reflected power (Prefl) and the transmitted power (Pout) have been measured by the VNA as a function of EM wave frequency in two technically important frequency bands - in 700 MHz to 3 GHz part of the ultra-high frequency (UHF) band and in the X-band, covering 8 to 12 GHz. From the measured data, Shielding Effectiveness in dB unit = 10 log (Pout / Pin) and Reflection Effectiveness in dB = 10 log (Prefl / Pin) have been calculated and studied for all the samples, with the results presented and discussed. In particular, our substitution of expensive metal powders by fine metallic turnings, available as waste from mechanical workshops, reduces the cost of polymer-metal composites substantially, retaining high shielding i.e. low transmission (down to -33dB in 08 to 12 GHz range).

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Li, Hongyan, Le Lu, Hongli Liu, Jiangang Wang, Jing Li, Bo Zhang, and Ruyi Li. "Loads transfer behavior of graphene oxide/halloysite organic-inorganic hybrid aerogel: Motion of polymer ‘bridge’." Ceramics International 47, no. 9 (May 2021): 11829–39. http://dx.doi.org/10.1016/j.ceramint.2021.01.022.

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Petrova, Valentina A., Iosif V. Gofman, Natallia V. Dubashynskaya, Alexey S. Golovkin, Alexander I. Mishanin, Elena M. Ivan’kova, Dmitry P. Romanov, et al. "Chitosan Composites with Bacterial Cellulose Nanofibers Doped with Nanosized Cerium Oxide: Characterization and Cytocompatibility Evaluation." International Journal of Molecular Sciences 24, no. 6 (March 12, 2023): 5415. http://dx.doi.org/10.3390/ijms24065415.

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In this work, new composite films were prepared by incorporating the disintegrated bacterial cellulose (BCd) nanofibers and cerium oxide nanoparticles into chitosan (CS) matrices. The influence of the amount of nanofillers on the structure and properties of the polymer composites and the specific features of the intermolecular interactions in the materials were determined. An increase in film stiffness was observed as a result of reinforcing the CS matrix with BCd nanofibers: the Young’s modulus increased from 4.55 to 6.3 GPa with the introduction of 5% BCd. A further increase in Young’s modulus of 6.7 GPa and a significant increase in film strength (22% increase in yield stress compared to the CS film) were observed when the BCd concentration was increased to 20%. The amount of nanosized ceria affected the structure of the composite, followed by a change in the hydrophilic properties and texture of the composite films. Increasing the amount of nanoceria to 8% significantly improved the biocompatibility of the films and their adhesion to the culture of mesenchymal stem cells. The obtained nanocomposite films combine a number of favorable properties (good mechanical strength in dry and swollen states, improved biocompatibility in relation to the culture of mesenchymal stem cells), which allows us to recommend them for use as a matrix material for the culture of mesenchymal stem cells and wound dressings.

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Natrayan, L., Yenda Srinivasa Rao, Puthalapattu Reddy Prasad, Kul Bhaskar, Pravin P. Patil, and Dereje Bayisa Abdeta. "Biosynthesis-Based Al2O3 Nanofiller from Cymbopogon citratus Leaf/Jute/Hemp/Epoxy-Based Hybrid Composites with Superior Mechanical Properties." Bioinorganic Chemistry and Applications 2023 (April 20, 2023): 1–8. http://dx.doi.org/10.1155/2023/9299658.

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Metallic nanoparticles (NPs) manufactured by ecofriendly strategies have also received much interest because of their elastic scattering properties and performance in nanomaterials. Aluminium oxide nanomaterials stand out among nanomaterials due to their tremendous uses in ceramic products, fabrics, therapeutic agents, catalyst supports, sewage sludge, and biosensors. The current paper investigates the effect of the nanoparticle composition and layer sequential on the mechanical characteristics of jute (J)-hemp (H) incorporated with an aluminium oxide polymer composite. NaOH is used to change the physical aspects of both plant fibres. A total of 20 specimens were tested with varying stacking sequences and padding weight ratios. Mechanical properties like a nanocomposite’s tension, bending, and ILSS was measured. Stacked series and flowability substantially impact the nanocomposite. The Group 3 nanocomposite with 2% Al2O3 has the highest tensile strength, 54.28% of the Group 1 and 2 combinations. The stack series significantly influences the material properties of nanomaterials. Because of the alternating layers of natural fabrics, Group 4 specimens have the maximum flexural strength. Group 3 composite materials have the highest ILSS because they have hemp on the outermost surface. It has been discovered that Group 4 material with a 2% Al2O3 concentration is possibly the most substantial material. The existence of Al2O3 nanoparticles in the green synthesis was confirmed by XRD analysis.

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Hong, Gwang-Wook, Sivalingam Ramesh, Joo-Hyung Kim, Hyeon-Ju Kim, and Ho-Saeng Lee. "Synthesis and Properties of Cellulose-Functionalized POSS-SiO2/TiO2 Hybrid Composites." Journal of Nanoscience and Nanotechnology 15, no. 10 (October 1, 2015): 8048–54. http://dx.doi.org/10.1166/jnn.2015.11237.

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The mechanical, thermal, optical, electrical and morphological properties of cellulose, an excellent natural biomaterial, can be improved by organic-inorganic hybrid composite methods. Based on the pristine properties of cellulose, the preparation of cellulose-metal oxide hybrid nanocomposites using a dispersion process of nanoparticles into the cellulose host matrix by traditionalmethods, has limitations. Recently, the functionalized cellulose-polymer-basedmaterials were considered to be an important class of high-performance materials, providing the synthesis of various functional hybrid nanocomposites using a sol-gel method. Transparent cellulose-POSS-amine-silica/titania hybrids were prepared by an in-situ sol-gel process in the presence of γ-aminopropyltrimethoxylsilane (γ-APTES). The methodology involves the formation of covalent bonding between the cellulose- POSS amine and SiO2/TiO2 hybrid nanocomposite material. An analysis of the synthesized hybrid material by Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, differential thermal calorimetry, scanning electron microscopy, and transmission electron microscopy indicated that the silica/titania nanoparticles were bonded covalently and dispersed uniformly into the cellulose-POSS amine matrix. In addition, biological properties of the cellulose-POSSsilica/titania hybrid material were examined using an antimicrobial test against pathogenic bacteria, such as Bacillus cereus (F481072) and E.coli (ATCC35150) for the bacterial effect.

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Rudenko, Aleksandr, Alexander Biryukov, Oleg Kerzhentsev, Roman Fediuk, Nikolai Vatin, Yuriy Vasilev, Sergey Klyuev, Mugahed Amran, and Maciej Szelag. "Nano- and Micro-Modification of Building Reinforcing Bars of Various Types." Crystals 11, no. 4 (March 24, 2021): 323. http://dx.doi.org/10.3390/cryst11040323.

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Fiber-reinforced plastic (FRP) rebar has drawbacks that can limit its scope, such as poor heat resistance, decrease its strength over time, and under the influence of substances with an alkaline medium, as well as the drawback of a low modulus of elasticity and deformation. Thus, the aim of the article is the nano- and micro-modification of building reinforcing bars using FRP rebars made of basalt fibers, which were impregnated with a thermosetting polymer binder with micro- or nanoparticles. The research discusses the major results of the developed composite reinforcement with the addition of micro- and nanosized particles. The microstructure of FRP has been studied using scanning electron microscopy. It was revealed that dispersion-strengthened polymer composites with the inclusion of microsilica (SiO2) and nanosized aluminum oxide (Al2O3) particles have a much higher modulus of elasticity and strength when compared with the original polymer materials. In the course of the experiment, we also studied the retained plastic properties that are characterized by the absence of fragility. However, it was found that the high strength of materials was attained with a particle size of 10–500 nm, evenly distributed in the matrix, with an average distance between particles of 100–500 nm. It was also exhibited that composite reinforcement had improved the adhesion characteristics in comparison with both steel reinforcement (1.5–2 times, depending on the diameter), and with traditional unmodified FRP rebar (about 1.5 times). Thus, the use of micro-/nanosized powders increased the limit of the possible temperature range for the use and application of polymeric materials by almost two times, up to 286–320 °C, which will undoubtedly expand the range of the technological applications of products made of these materials.

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Kaimonov, Maksim, Tatiana Shatalova, Yaroslav Filippov, and Tatiana Safronova. "Fine Biocompatible Powders Synthesized from Calcium Lactate and Ammonium Sulfate." Ceramics 4, no. 3 (July 4, 2021): 391–96. http://dx.doi.org/10.3390/ceramics4030028.

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Fine biocompatible powders with different phase compositions were obtained from a 0.5 M solution of ammonium sulfate (NH4)2SO4 and calcium lactate Ca(C3H5O3)2. The powder after synthesis and drying at 40 °C included calcium sulfate dehydrate CaSO4·2H2O and calcite CaCO3. The powder after heat treatment at 350 °C included β-hemihydrate calcium sulfate β-CaSO4·0.5H2O, γ-anhydrite calcium sulfate γ-CaSO4 and calcite CaCO3. The phase composition of powder heat-treated at 600 °C was presented as β-anhydrate calcium sulfate β-CaSO4 and calcite CaCO3. Increasing the temperature up to 800 °C leads to the sintering of a calcium sulfate powder consisting of β-anhydrite calcium sulfate β-CaSO4 main phase and a tiny amount of calcium oxide CaO. The obtained fine biocompatible powders of calcium sulfate both after synthesis and after heat treatment at temperature not above 600 °C can be recommended as a filler for producing unique composites with inorganic (glass, ceramic, cement) or polymer matrices.

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Journal articles on the topic 'Inorganic Oxide-Polymer Composites'

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