Articles de revues : « Bio-nano-composites »

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R. Tittmann, Bernhard. « Nano mechanical behavior of bio composites ». International Journal of Biotechnology and Bioengineering 2, n^o 1 (2016) : 41–51. http://dx.doi.org/10.25141/2475-3432-2016-1.0041.

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Myndrul, Valerii, et Igor Iatsunskyi. « Nanosilicon-Based Composites for (Bio)sensing Applications : Current Status, Advantages, and Perspectives ». Materials 12, n^o 18 (6 septembre 2019) : 2880. http://dx.doi.org/10.3390/ma12182880.

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This review highlights the application of different types of nanosilicon (nano-Si) materials and nano-Si-based composites for (bio)sensing applications. Different detection approaches and (bio)functionalization protocols were found for certain types of transducers suitable for the detection of biological compounds and gas molecules. The importance of the immobilization process that is responsible for biosensor performance (biomolecule adsorption, surface properties, surface functionalization, etc.) along with the interaction mechanism between biomolecules and nano-Si are disclosed. Current trends in the fabrication of nano-Si-based composites, basic gas detection mechanisms, and the advantages of nano-Si/metal nanoparticles for surface enhanced Raman spectroscopy (SERS)-based detection are proposed.

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Cheng, Zheng Liang, Qing Hua Xu et Yang Gao. « Research Progress in Nano-Cellulose Modification ». Advanced Materials Research 627 (décembre 2012) : 859–63. http://dx.doi.org/10.4028/www.scientific.net/amr.627.859.

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As an environmentally friendly material prepared from renewable natural resources, nano-cellulose demonstrates excellent properties, including high crystallinity, high purity, high surface area, unique optical properties, and high Young's modulus. Furthermore, it has the advantages of bio-based materials such as light-weight, bio-degradable, bio-compatible, and renewable. Therefore, the nano-cellulose shows a great potential for developing new composite materials with high performances. This paper summarizes the ways for chemically modifying nano-cellulose to obtain better dispersion and improve its compatibility with nonpolar or hydrophobic matrices in nano-composites.

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KOTHARI, SHARAT. « Nanoclay biopolymer composites : Synthesis, characterization and nitrogen release under controlled conditions ». Annals of Plant and Soil Research 24, n^o 3 (1 août 2022) : 434–38. http://dx.doi.org/10.47815/apsr.2021.10188.

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As the production sector of N fertilizer challenged by energy crisis of the world and consumption sector is challenged by the environmental impacts, there is an urgent need to improve the nitrogen use efficiency for the sustainable growth of agriculture sector. The controlled release/ slow-release N fertilizers are smart choices to serve this purpose. So, this manuscript aims to synthesise nano clay bio-polymer composites (NCBPC) and using it for controlled N release. Nano clay bio-polymer composites were prepared by aqueous copolymerization of acrylic acid with acrylamide in presence of bentonite nano clay and starch as a partial replacement for synthetic polymers. Maize and wheat flour (maida) were used as starch source at 20 and 30% replacement level to synthesise different NCBPC products. The resulting products were characterized using FTIR and SEM which revealed the participation of bentonite and starch in the polymerization reaction at the nano level. The incubation study in soil disclosed the slow-release of nitrogen by these materials. Therefore, bentonite clay with cereal grain flours may be used for the synthesis of nano clay bio-polymer composites for slow-release of nitrogen.

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Daghigh, Vahid, Thomas E. Lacy, Hamid Daghigh, Grace Gu, Kourosh T. Baghaei, Mark F. Horstemeyer et Charles U. Pittman. « Machine learning predictions on fracture toughness of multiscale bio-nano-composites ». Journal of Reinforced Plastics and Composites 39, n^o 15-16 (27 avril 2020) : 587–98. http://dx.doi.org/10.1177/0731684420915984.

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Tailorability is an important advantage of composites. Incorporating new bio-reinforcements into composites can contribute to using agricultural wastes and creating tougher and more reliable materials. Nevertheless, the huge number of possible natural material combinations works against finding optimal composite designs. Here, machine learning was employed to effectively predict fracture toughness properties of multiscale bio-nano-composites. Charpy impact tests were conducted on composites with various combinations of two new bio fillers, pistachio shell powders, and fractal date seed particles, as well as nano-clays and short latania fibers, all which reinforce a poly(propylene)/ethylene–propylene–diene-monomer matrix. The measured energy absorptions obtained were used to calculate strain energy release rates as a fracture toughness parameter using linear elastic fracture mechanics and finite element analysis approaches. Despite the limited number of training data obtained from these impact tests and finite element analysis, the machine learning results were accurate for prediction and optimal design. This study applied the decision tree regressor and adaptive boosting regressor machine learning methods in contrast to the K-nearest neighbor regressor machine learning approach used in our previous study for heat deflection temperature predictions. Scanning electron microscopy, optical microscopy, and transmission electron microscopy were used to study the nano-clay dispersion and impact fracture morphology.

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S. Kashan, Jenan,, et Saad M. Ali. « 3D Model of Bone Scaffolds Based on the Mechanical Behaviour for a Hybrid Nano Bio-composites ». journal of Mechanical Engineering 17, n^o 2 (15 juillet 2020) : 45–67. http://dx.doi.org/10.24191/jmeche.v17i2.15300.

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Ceramic/polymer Nano composites in the view of possessing design uniqueness and property combinations have gained a great attention and reported to be the materials of the 21st century that are not found in conventional composites. In the present work, an attempt has been made to study, develop and improve the bio-mechanic for a designed and fabricated Ceramic/polymer bio-composite for a human natural bone repair and replacement in the case of complex fracture and bone diseases by adding the Nano fillers ceramic particles to the Polymer Matrix Nano composites (PMNC) for fabricated a hybrid Titanium dioxide and yttria stabilized zirconia reinforced high density polyethylene (HDPE) matrix bio-composites properties. These bioactive composites have been investigated by using hot pressing technique at different compression pressures of (30, 60, and 90 MPa) at a compounding temperature of (180, 190, and 200 °C). The SOLIDWORKS 17.0 and the finite element ANSYS 15.7 software programs were used to the simulation, modelling and analysing of femur bone biomechanics that can withstand the highest stresses and strains. The response surface methodology (RSM) technique was used to improve and verify the results. For all the fabricated Nano bio-composites systems, the results showed that the obtained output parameters values were increased with increasing the process input parameters, also the vice versa for the strain energy and equivalent elastic strain values, also the Nano ceramic compositions represented the main factor influenced the results. The main investigates results of the current research deduced that for the increase of the Nano ceramic powder (TiO2) contain from 1% to 10%, the compression fracture strength and the micro-Vickers hardness values increased by 50% and by 8.45%, respectively, and when adding 2% of zirconia (ZrO2), an additional increase in the compression fracture strength and micro hardness by 28.21% and 40.19% achieved, respectively. When using 10% TiO2 + 2% ZrO2/HDPE bio-composite at highest compact temperature of 200 °C and compounding pressure of 90 MPa, the strain energy and the equivalent elastic strain reduced by 82.69% and 14.53% when compared with using of 1% TiO2 content. While when increasing the nano ceramic content from 1% to 10% without adding the ZrO2 nano filler, they reduced by 142.25% and 67.81%, respectively. The maximum equivalent von Misses stress obtained is equal to 39.957MPa and when increasing the nano ceramic content from 1% to 10%, the stress safety factors and fatigue live values increased by 58.38% and by 46.28%, respectively and when adding 2% of zirconia (ZrO2), the stress safety factor reached its maximum values, with an additional increase in its values by 21.42% and 69.40%, respectively. These results give great choices to use successful in vivo tests and for a better life performance with any age, patient status and degree of injury.

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Ali, M. S., A. A. Al-Shukri, M. R. Maghami et C. Gomes. « Nano and bio-composites and their applications : A review ». IOP Conference Series : Materials Science and Engineering 1067, n^o 1 (1 février 2021) : 012093. http://dx.doi.org/10.1088/1757-899x/1067/1/012093.

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Okamoto, Mitsuyo, E. Iwai, H. Hatta, Hitoshi Kohri et Ichiro Shiota. « New Fabrication Process of Nano–Composites by Biomimetic Approach ». Advances in Science and Technology 58 (septembre 2008) : 60–65. http://dx.doi.org/10.4028/www.scientific.net/ast.58.60.

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In bio-systems, nano-composites with complex micro-structures are formed by self-assembly only using low energy at room temperature. If these mechanisms of biological tissue are identified, we can possibly propose a new process to fabricate composites by mimicking tissue formation in vivo. As a bio-material, we paid attention to bio-tissue reinforced with collagen fibrils. Collagen fibrils are of baculiform; Thus the self-assembly process through liquid crystalline transition has been proposed by a French group [1]. In the present study, factors controlling liquid crystalline transition, e.g. concentration and pH, are discussed using collagen solution. When liquid crystalline phase is produced, aligned molecules exhibits optical anisotropy. This anisotropy was observed with a polarized optical microscopy (POM). By observations with POM, development of cholesteric phase in collagen solution was clarified.

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Oliver, Daniel, Monika Michaelis, Hendrik Heinz, Victor V. Volkov et Carole C. Perry. « From phage display to structure : an interplay of enthalpy and entropy in the binding of the LDHSLHS polypeptide to silica ». Physical Chemistry Chemical Physics 21, n^o 8 (2019) : 4663–72. http://dx.doi.org/10.1039/c8cp07011c.

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Semba, Takeshi, Akihiro Ito, Takahiro Uesaka, Kazuo Kitagawa, Kunio Taguma, Masataka Tawara, Hiroyuki Yano et Akihiro Sato. « Bio-Composites Composed of Cellulose nano-fiber and polyamide 11 ». Seikei-Kakou 26, n^o 7 (2014) : 355–58. http://dx.doi.org/10.4325/seikeikakou.26.355.

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Deepak, K., N. Srinivasa Reddy et T. V. Seshaiah Naidu. « Thermosetting Polymer and Nano Clay Based Natural Fiber Bio- Composites ». Procedia Materials Science 10 (2015) : 626–31. http://dx.doi.org/10.1016/j.mspro.2015.06.095.

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Boonsorn, Wathun, Sukasem Watcharamaisakul et Boris Golman. « Fabrication of Al₂O₃/ZrO₂ Micro/Nano Composites Using Powder Alkoxide Mixtures ». Advanced Materials Research 931-932 (mai 2014) : 132–36. http://dx.doi.org/10.4028/www.scientific.net/amr.931-932.132.

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Al2O3/ZrO2 composites have been investigated as the bio-inert material. In the present work Al2O3/ZrO2 Micro/Nano composites were prepared by colloidal method. The effects of the concentration of zirconium propoxide and the sintering temperature were studied on the distribution of ZrO2 nano-grainsin Al2O3 matrix and mechanical properties of composites. XRD patterns for all compositions showed a single phase of a-Al2O3, and the tetragonal and monoclinic ZrO2 phases. Samples sintered at 1650°C demonstrated the high bulk density with value of 86-92% of theoretical density. ZrO2 nano-grains were dispersed within Al2O3 grain and the grain boundary. The sample of the highest flexural strength of 710 MPa was synthesized using 100% Zr propoxide solution and sintered at 1650o C. The flexural strength was found to increase with increasing the concentration of Zr propoxide and sintering temperature.

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Palazzo, B., D. Izzo, F. Scalera, A. N. Cancelli et F. Gervaso. « Bio-Hybrid Scaffolds for Bone Tissue Engineering : Nano-Hydroxyapatite/Chitosan Composites ». Key Engineering Materials 631 (novembre 2014) : 300–305. http://dx.doi.org/10.4028/www.scientific.net/kem.631.300.

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Natural bone ECM is a hierarchical nanocomposite made of an inorganic phase deposited within an organic matrix. In order to mimic the bone highly organized hybrid structure and functionality, strategies that allow assembling ceramic and polymer phase can be applied. To this aim, we investigated aninsitugrowth method able to nucleate a nanoHydroxyapatite (nHAp) phase into and around the interconnected porous structure of chitosan sponges. By increasing the calcium and phosphate concentration in the meta-stable solution used for the nHAp nucleation, the inorganic phase raised proportionally, in the range 10%-30% wt. In order to be compared with nHAp loaded scaffolds, pure chitosan samples have been produced by cross-linking biopolymer with arginine. Moreover, nHAp loaded samples, containing the 20 % wt of inorganic phase have been prepared by simply mixing low crystalline nHAp powders with the chitosan gel. Thein situnucleation method highlighted evident advantages in terms of nanophase distribution and mechanical performances with respect to a merely mixing procedure.

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Liang, Ji-Zhao, Chak-Yin Tang, Lin Zhou, Liu He et Chi-Pong Tsui. « Melt density and flow property of PDLLA/nano-CaCO3 bio-composites ». Composites Part B : Engineering 42, n^o 7 (octobre 2011) : 1897–900. http://dx.doi.org/10.1016/j.compositesb.2011.06.011.

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V, Mohanavel, Suresh Kumar S, Ravichandran M, Rajkumar Sivanraju, Palanivel Velmurugan et Ram Subbiah. « Influence of Nanofillers on the Mechanical Characteristics of Natural Fiber Reinforced Polymer Composites ». ECS Transactions 107, n^o 1 (24 avril 2022) : 12513–24. http://dx.doi.org/10.1149/10701.12513ecst.

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For the first time, natural fibers are being considered as a viable alternative to traditional synthetic fibers. These bio-composites were created using epoxy resin, nano-sized fine nano-tamarind shell ash particles, and water hyacinth fibers in this experimental work. Nano tamarind shell ash particles (0, 1, 3, 5, 7, and 9 wt. percent) were mixed with epoxy resin and water hyacinth fibers to create six different composite mates by the compression moulding machine. The composite specimens are prepared from the mats using the water jet machining method, according to ASTM specifications. Mechanical properties of composite specimens have been determined using tensile, flexural, and impact tests under standard testing circumstances. According to the test results, the composites with nano tamarind shell ash particles in the weight percentage of five percent greatly improve their tensile and flexural capabilities. Increased incorporation of fine nano tamarind shell ash particles in composite specimens has reduced their impact energy and impact strength.

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Mithaq R. Mohammed, Israa H. Hilal et Shurooq J. Jabbar. « The influence of (Mn) Nano - particles on mechanical, physical, and biological properties of (PMMA/PVA-Mn) Nano - composite used for denture base ». International Journal of Research in Pharmaceutical Sciences 11, n^o 2 (7 mai 2020) : 2320–25. http://dx.doi.org/10.26452/ijrps.v11i2.2208.

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The (PMMA/PVA–Mn) Nano-composites films were prepared via a photopolymerization method with different percentages (0.0%, 0.1%, and 0.2%) Of Mn with (20%PVA /80%PMMA,30%PVA/70%PMMA ad 40%PVA/60% PMMA) . The structural, bacterial, and mechanical properties of Nano-composites, were studied, X-ray properties of Mn nanoparticle which studied. Scanning electron microscopy analysis was employed to evaluate the morphological and structural properties of each thin film Nanocomposite. Moreover, the effect of Streptococcus mutans antibacterial of those materials was analyzed. Results: The morphological studies represented that both non-functionalized and Bio functionalized manganese oxide NPs (MnNPs) formed are of spherical morphology but exhibited with a difference in size about 20 nm and 27-40 nm, respectively. The performance of the antimicrobial activity. The results are revealed that the Bio functionalized MoNPs showed higher antibacterial. Results show that values increase in each of Mn Nanoparticle and with different concentrations of (PVA/PMMA) polymer, then decrease alternately less value of volume fraction of fillers. Young modules values increase alternately by the volume fraction of fillers.

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Bangar, Sneh Punia, et William Scott Whiteside. « Nano-cellulose reinforced starch bio composite films- A review on green composites ». International Journal of Biological Macromolecules 185 (août 2021) : 849–60. http://dx.doi.org/10.1016/j.ijbiomac.2021.07.017.

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Nathanael, A. Joseph, Jun Hee Lee, D. Mangalaraj, S. I. Hong et Y. H. Rhee. « Multifunctional properties of hydroxyapatite/titania bio-nano-composites : bioactivity and antimicrobial studies ». Powder Technology 228 (septembre 2012) : 410–15. http://dx.doi.org/10.1016/j.powtec.2012.06.001.

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Shu, Rui, Xiaosong Jiang, Hongliang Sun, Zhenyi Shao, Tingfeng Song et Zhiping Luo. « Recent researches of the bio-inspired nano-carbon reinforced metal matrix composites ». Composites Part A : Applied Science and Manufacturing 131 (avril 2020) : 105816. http://dx.doi.org/10.1016/j.compositesa.2020.105816.

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Mohamed, Khaled R., Hanan H. Beherei et Zenab M. El-Rashidy. « In vitro study of nano-hydroxyapatite/chitosan–gelatin composites for bio-applications ». Journal of Advanced Research 5, n^o 2 (mars 2014) : 201–8. http://dx.doi.org/10.1016/j.jare.2013.02.004.

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Aversa, Raffaella, Relly Victoria Virgil Petrescu, Antonio Apicella et Florian Ion Tiberiu Petrescu. « A nanodiamond for structural biomimetic scaffolds ». Engineering review 39, n^o 1 (2019) : 81–89. http://dx.doi.org/10.30765/er.39.1.9.

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Bio-mechanically active scaffolds for tissue engineering combining hydrophilic polymeric matrix and nano-diamond fillers properties are presented and discussed in this paper. The resulting scaffolding materials revealed remarkable mechanical and biological properties to be exploited in advanced biomedical applications. The novel hybrid material is based on 2 and 5 volume % of detonation nano-diamond particles in a hydrophilic poly-(hydroxyl-ethylmethacrylate) matrix. According to its mechanical and biological properties, the nanocomposite shows a hybrid nature. The base analytical procedures for the preparation of the hybrid nanocomposites and some preliminary mechanical characteristics are presented. The proposed hybrid system has been considered for potential biomimetic, osteoconductive and osteoinductive scaffolds application in bio-mechanically active bone scaffolds for osteoblast and stem cell differentiation and growth. These more rigid hybrid nano-composites are predicted to possess improved mechanical strength overcoming the mechanical weaknesses of traditional hydrogels clinically utilized for bone regeneration.

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Chen, Wen Shuai, Hai Peng Yu, Peng Chen, Nai Xiang Jiang, Jiang Hua Shen, Yi Xing Liu et Qing Li. « Preparation and Morphological Characteristics of Cellulose Micro/Nano Fibrils ». Materials Science Forum 675-677 (février 2011) : 255–58. http://dx.doi.org/10.4028/www.scientific.net/msf.675-677.255.

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Cellulose micro/nano fibrils generated from biomass are relative new reinforcing materials for polymer composites, which have potential lightweight and high strength and are renewable. In the present study, the preparation method of extracting cellulose micro/nano fibrils from wood was introduced. After successful disintegration, the morphological characteristics of the wood fibers, purified cellulose fibers, cellulose fibers activated by ultrasonic-wave and cellulose micro/nano fibrils after homogenization treatment, were compared by visual examination and scanning electron microscopy. The results showed that cellulose micro/nano fibrils have been efficiently extracted from wood, which have great potential in the application areas of papermaking, bio-nanocomposites, food, cosmetics/skin cream, medical/pharmaceutical, and so on.

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Doineau, Estelle, Bernard Cathala, Jean-Charles Benezet, Julien Bras et Nicolas Le Moigne. « Development of Bio-Inspired Hierarchical Fibres to Tailor the Fibre/Matrix Interphase in (Bio)composites ». Polymers 13, n^o 5 (5 mars 2021) : 804. http://dx.doi.org/10.3390/polym13050804.

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Several naturally occurring biological systems, such as bones, nacre or wood, display hierarchical architectures with a central role of the nanostructuration that allows reaching amazing properties such as high strength and toughness. Developing such architectures in man-made materials is highly challenging, and recent research relies on this concept of hierarchical structures to design high-performance composite materials. This review deals more specifically with the development of hierarchical fibres by the deposition of nano-objects at their surface to tailor the fibre/matrix interphase in (bio)composites. Fully synthetic hierarchical fibre reinforced composites are described, and the potential of hierarchical fibres is discussed for the development of sustainable biocomposite materials with enhanced structural performance. Based on various surface, microstructural and mechanical characterizations, this review highlights that nano-objects coated on natural fibres (carbon nanotubes, ZnO nanowires, nanocelluloses) can improve the load transfer and interfacial adhesion between the matrix and the fibres, and the resulting mechanical performances of biocomposites. Indeed, the surface topography of the fibres is modified with higher roughness and specific surface area, implying increased mechanical interlocking with the matrix. As a result, the interfacial shear strength (IFSS) between fibres and polymer matrices is enhanced, and failure mechanisms can be modified with a crack propagation occurring through a zig-zag path along interphases.

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Ozimek, Jan, et Krzysztof Pielichowski. « Recent Advances in Polyurethane/POSS Hybrids for Biomedical Applications ». Molecules 27, n^o 1 (22 décembre 2021) : 40. http://dx.doi.org/10.3390/molecules27010040.

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Advanced organic-inorganic materials-composites, nanocomposites, and hybrids with various compositions offer unique properties required for biomedical applications. One of the most promising inorganic (nano)additives are polyhedral oligomeric silsesquioxanes (POSS); their biocompatibility, non-toxicity, and phase separation ability that modifies the material porosity are fundamental properties required in modern biomedical applications. When incorporated, chemically or physically, into polyurethane matrices, they substantially change polymer properties, including mechanical properties, surface characteristics, and bioactivity. Hence, this review is dedicated to POSS-PU composites that have recently been developed for applications in the biomedical field. First, different modes of POSS incorporation into PU structure have been presented, then recent developments of PU/POSS hybrids as bio-active composites for scaffolds, cardiovascular stents, valves, and membranes, as well as in bio-imaging and cancer treatment, have been described. Finally, characterization and methods of modification routes of polyurethane-based materials with silsesquioxanes were presented.

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Lu, Zhi Hua, Dong Mei Zhao et Kang Ning Sun. « Preparation and Characterization of a Bio-Composites Scaffold Containing Nano-Hydroxyapatite /Carboxymethyl Chitosan ». Advanced Materials Research 476-478 (février 2012) : 2055–58. http://dx.doi.org/10.4028/www.scientific.net/amr.476-478.2055.

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In this study, a genipin cross linked scaffold containing nano-hydroxyapatite (n-HAp) and carboxymehthyl chitosan (CMCS) was developed by freeze drying technique. The scaffolds were characterized using FTIR, XRD and SEM. The cytotoxicity of the scaffolds was compared with scaffolds cross linked by glutaraldehyde, and the Young’s modulus was also tested. FTIR and XRD results indicated that CMCS’s hydroxyl group, amino and amide regulated the n-HAp crystallization process, which results in the nano homogenous distribution of n-HAp and provided nano topographical features for nanohybrid scaffolds. SEM images revealed the scaffolds had porous structure and the pores were interconnected with an average diameter of 150 μm, which was profit for the growth of tissues. Cell morphology showed the genipin cross linked scaffolds had less toxicity and more facility for adhesion and proliferation of cells. Great mechanical properties of the scaffolds indicate their potential use in bone tissue engineering.

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H, Uddin, M., et Haque, M. M. « Preparation and Characterization of Cellulose Nanoparticles from Agricultural Wastes and Their Application in Polymer Composites ». Scholars International Journal of Chemistry and Material Sciences 6, n^o 1 (10 janvier 2023) : 18–23. http://dx.doi.org/10.36348/sijcms.2023.v06i01.002.

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, Page no - | ABSTRACT | PDF | FULL TEXT | e-PUB Background: The development of innovative eco-sustainable bio-nano-composites materials based on cellulose nanomaterials obtained from agricultural waste such as rapeseed plant straw and polymeric materials with improved properties. At first, cellulose was extracted from rapeseed plant straw and cellulosic and no cellulosic materials were estimated. It was found that the rapeseed plant straw contained about 43.48 wt.% cellulosic materials and 56.52 wt.% no cellulosic materials. It was also found that the rapeseed plant straw content about 34.84 wt.% α- cellulose. Then, nano-cellulose was prepared by acid hydrolysis of α -cellulose obtained from rapeseed plant straw. Poly vinyl acetate (PVAc) was prepared by soap free emulsion polymerization of vinyl monomer. Natural rubber (NR) collected as latex was oxidized by KMnO4. Blends of NR and oxidized NR with PVAc of different compositions such as NR60/PVAc40, NR40/PVAc60, ONR60/PVAc40, ONR40/PVAc60 were prepared by mixing NR latex and PVAc emulsion and followed by drying in an oven at 60°C. Composites of NR60/PVAc40 and ONR60/PVAc40 reinforced nano-cellulose (NC) were also prepared in similar way. The blends and composites were then characterized by FTIR, SEM, and Tensile test (TS). FTIR analysis confirmed the oxidation of NR and shown the variation of the functional groups in the blends and composites compared with the FTIR spectrum of NR, ONR and PVAc. SEM study exhibited that the nano-cellulose were dispersed within NR/PVAc and ONR/PVAc blends matrices with a little agglomeration. The tensile test results showed that the strength in composites was increased due to the reinforcing effect of nano-cellulose (NC). Objectives: The aim of this study is to assess the Preparation and characterization of binary blends of NR and oxidized NR with PVAc. Methods: This is an observational study. The study used to be carried out in the admitted patient’s Department of Applied Chemistry and Chemical Engineering, Islamic University, Kushtia-7003, Bangladesh. The duration of the period from Data was entered in MS Excel and Statistical analysis was done using SPSS trial version. Results: This study shows that the according to Constituent, Cellulose was 43.4822%, Alpha-Cellulose were 34.8427% and Cellulose were 8.6395%. And according to Source, Rice Straw were 32.15% %, Sugarcane were 41-43%, Rye Straw were 31.8-42.64%, Corn Stalks were 29.80% and Wheat Straw were 34-40%. Conclusion: Novel eco-friendly bio-nano-composites substances primarily based on renewable and sustainable assets namely natural rubber (NR) and nano-cellulose received from rapeseed plant straw as properly as poly vinyl acetate (PVAc) have been developed. In order to enhance the interfacial interactions amongst the composite factors such as NR, PVAc and NC, oxidation of the NR latex was once carried out by way of KMnO4 before blending mixing with PVAc emulsion and NC suspension.

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Daghigh, Vahid, Thomas E. Lacy, Hamid Daghigh, Grace Gu, Kourosh T. Baghaei, Mark F. Horstemeyer et Charles U. Pittman. « Heat deflection temperatures of bio-nano-composites using experiments and machine learning predictions ». Materials Today Communications 22 (mars 2020) : 100789. http://dx.doi.org/10.1016/j.mtcomm.2019.100789.

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Jogiya, Bhoomika, Kiran Chudasama, Vrinda Thaker et Mhir Joshi. « Synthesis and characterization of novel bio-material : Nano composites of hydroxyapatite and curcumin ». International Journal of Applied Ceramic Technology 15, n^o 1 (31 juillet 2017) : 148–60. http://dx.doi.org/10.1111/ijac.12754.

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Nyuk Khui, Perry Law, Rezaur Rahman, Abu Saleh Ahmed, Kuok King Kuok, Muhammad Khusairy Bin Bakri, Diana Tazeddinova, Zhumayeva Araigul Kazhmukanbetkyzy et Baibatyrov Torebek. « Morphological and thermal properties of composites prepared with poly(lactic acid), poly(ethylene-alt-maleic anhydride), and biochar from microwave-pyrolyzed jatropha seeds ». BioResources 16, n^o 2 (11 mars 2021) : 3171–85. http://dx.doi.org/10.15376/biores.16.2.3171-3185.

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The morphological and thermal properties of composites containing a bioplastic blend and micro/nano-sized biochar from pyrolyzed jatropha seeds from microwave pyrolyzed jatropha seeds were investigated using scanning electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, and differential scanning calorimetry. The biocomposite samples exhibited a brittle structure with a slightly ductile chip-like appearance. The Fourier transform infrared spectroscopy results for the PLA/PEMA/BC bio-composites were comparable to the PLA/BC biocomposites. A lower bio-filler content had more pronounced peak intensities than the higher bio-filler content biocomposites. The added PEMA compatibilizer in the PLA/PEMA/BC biocomposite showed more pronounced peaks, which indicated slightly improved bonding/interaction between the bio-filler and the matrix. Overall, increasing bio-filler content did not drastically affect the functional groups of the biocomposites. Thermogravimetric and differential scanning calorimetry analysis showed the developed biocomposites had a slight improvement in thermal stability, in comparison to the PLA sample. Improvements in the thermal stability of the PLA/PEMA/BC biocomposite could be attributed to the additional hydroxyl group, which was due to the added PEMA in the PLA and PLA/BC. According to the results of the analysis of the developed biocomposites, the biocomposites were more brittle and had reasonable thermal stability.

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NAIR, A. SREEKUMARAN, RENJIS T. TOM, V. R. RAJEEV KUMAR, C. SUBRAMANIAM et T. PRADEEP. « CHEMICAL INTERACTIONS AT NOBLE METAL NANOPARTICLE SURFACES — CATALYSIS, SENSORS AND DEVICES ». COSMOS 03, n^o 01 (novembre 2007) : 103–24. http://dx.doi.org/10.1142/s0219607707000244.

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In this paper, a summary of some of the recent research efforts in our laboratory on chemical interactions at noble metal nanoparticle surfaces is presented. The article is divided into five sections, detailing with (i) interactions of simple halocarbons with gold and silver nanoparticle surfaces at room temperature by a new chemistry and the exploitation of this chemistry in the extraction of pesticides from drinking water, (ii) interaction of biologically important proteins such as Cyt c, hemoglobin and myoglobin as well as a model system, hemin with gold and silver nanoparticles and nanorods forming nano–bio conjugates and their surface binding chemistry, (iii) formation of polymer–nano composites with tunable optical properties and temperature sensing characteristics by single and multi-step methodologies, (iv) nanomaterials-based flow sensors and (v) composites of noble metal nanoparticles and metallic carbon nanotubes showing visible fluorescence induced by metal–semiconductor transition.

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Zhao, Jian, Wei Li, Xin Dong et Jiying Chen. « Material Properties of Strontium Doped Bioactive Glasses/Hydroxyapatite Composite and Its Mechanism of Promoting Bone Repair ». Journal of Biomaterials and Tissue Engineering 11, n^o 12 (1 décembre 2021) : 2313–20. http://dx.doi.org/10.1166/jbt.2021.2853.

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Based on bioactive glasses (BG) of 58S, sol–gel method is used to prepare strontium oxide substituted bioactive glasses (SrO-BG) with different strontium content. SrO-BG and nano hydroxyapatite (HAp) composite materials were synthesized using precipitation method. The phase composition and morphologies of the prepared materials were examined by x-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. The dissolution and bio-mineralization of SrO-BG and SrO-BG/HAp composites in SBF are investigated by immersion method. The effects of secretion components of macrophages regulated by strontium doped SrO-BG/HAp composites on the osteogenic differentiation (OD) of bone marrow mesenchymal stem cells (BMSCs) are analyzed. The results demonstrate that the SrO-BG can inhibit the dissolution of BG. Different proportions of SrO-BG/HAp composites show good ability to induce HAp in SBF. The bio-mineralization ability of SrO-BG/HAp composites increases with the increase of SrO-BG content. The results of dissolution behavior and bio-mineralization of SrO-BG/HAp composite show that the dissolution rate of each ion can be controlled by adjusting the content of SrO-BG in the composite, and then the degradation rate can effectively be controlled. The results of in vitro experiments show that SrO-BG/HAp composites with 2%, 5% and 8% strontium content are more effective in promoting M2 polarization of macrophages than SrO-BG/HAp composites with 0% strontium content. Among them, 5% strontium doped SrO-BG/HAp has the strongest effect on M2 polarization of macrophages, and the secretion of macrophages regulated by 5% strontium doped SrO-BG/HAp composite is more conducive to bone repair.

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Wahby, Mohamed H., Ayman M. Atta, Yaser M. Moustafa, Abdelrahman O. Ezzat et Ahmed I. Hashem. « Hydrophobic and Superhydrophobic Bio-Based Nano-Magnetic Epoxy Composites as Organic Coating of Steel ». Coatings 10, n^o 12 (9 décembre 2020) : 1201. http://dx.doi.org/10.3390/coatings10121201.

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New epoxy resin hardeners were prepared from the reaction of p-nonylphenol and cardanol glycidylether with pentaethylenehexamine (PEHA) to produce hydrophobic polyamines. They were used as capping to produce superhydrophobic magnetite nanoparticles (Fe3O4 NPs). The chemical structures, thermal stability, morphologies, and particle sizes diameters were evaluated to confirm the hydrophobicity of dicardanoxy (DCHI) and dinonylphenoxy (HPHI) polyamines. The curing exothermic reaction of bisphenol A diglycidyl ether (DGEB) epoxy resin with DCHI, HPHI, or their Fe3O4 NPs was investigated by dynamic mechanical analyzer and differential scanning calorimetry. The cured epoxy networks crosslinking densities, storage modulus, and glass transition temperatures were determined and correlated to epoxy networks chemical compositions. DGEB/DCHI and DGEB/HPHI with their stoichiometric ratio embedded with their Fe3O4 NPs were applied on the rough steel surface to produce hydrophobic and superhydrophobic epoxy coatings. The wetting characteristics of the cured epoxy nanocomposites were evaluated from seawater contact angle (WCA) measurements to prove the formation of superhydrophobic coatings in the presence of DCHI-Fe3O4 NPs having WCA > 150°. The excellent adhesion, mechanical, and anti-corrosion performances using DGEB/DCHI and DGEB/HPHI epoxy nanocomposites were obtained on the steel surfaces in the presence of seawater corrosive environment.

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Mohsan, Ali Hasan, et Nadia A. Ali. « Electro spinning of Polycaprolactone / Hydroxyapatite Composites in Wound Dressing Application ». Iraqi Journal of Physics (IJP) 20, n^o 1 (1 mars 2022) : 14–25. http://dx.doi.org/10.30723/ijp.v20i1.703.

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Polycaprolactone polymer is widely used in medical applications due to its biocompatibility. Electro spinning was used to create poly (ε- caprolactone) (PCL) nanocomposite fiber mats containing hydroxyapatite (HA) at concentrations ranging from 0.05 to 0.4% wt. The chemical properties of the fabricated bio composite fibers were evaluated using FTIR and morphologically using field-emission scanning-electron microscopy (FESEM), Porosity, contact angle, as well as mechanical testing(Young Modulus and Tensile strength) of the nanofibers were also studied. The FTIR results showed that all the bonds appeared for the pure PCL fiber and the PCL/HA nano fibers. The FESEM nano fiber showed that the fiber diameter increased from 54.13 to 155.79 (nm) at the HA values from (0.05 % and 1%wt.). Porosity, wettability of (PCL/HA) composites has improved, and the contact angle has decreased from 103.59o to 85.57o for fibrous scaffolds. The inclusion of hydroxyapatite increased the tensile strength of nano fiber scaffolds, and the maximum tensile strength of 0.4% percent was about 0.127 MPa, with a lowering in elongation to 40%.

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Singh, Devendra Kumar, et Rajesh Kumar Verma. « A critical review on ultra high molecular weight polyethylene (UHMWPE) for prosthesis and implant functions ». E3S Web of Conferences 309 (2021) : 01018. http://dx.doi.org/10.1051/e3sconf/202130901018.

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Polymer composites benefit joint prostheses and implants in biomaterials due to their high strength, reliability, and elasticity modules. The addition of nanoparticles into the polymer-based matrix has effectively demonstrated up-grading wear resistance and implant strength improvement. Therefore, due to the elevated surface area and immense properties, considerable attention has been paid to research in integrating nanoparticles for a wide variety of functions. The UHMWPE is extensively used to develop prosthesis and orthopedic operations due to exceptional mechanical and biocompatible features. The various research studies revealed the fabrication of bio nanocomposites with the polymer matrix possesses superior biocompatibility and durability. This paper presents a critical review of UHMWPE for the latest advancement in polymeric implants by adding different nanoparticles. Another exciting aspect of the proposed work is the addition of different organic (carbon, polymeric) and inorganic (metallic and metal oxides) nanoparticles to develop bio-nano composites. An effort has been made to highlight the exceptional features of modified UHMWPE by supplementing nanofillers for biomedical functions.

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Badgar, Khandsuren, Neama Abdalla, Hassan El-Ramady et József Prokisch. « Sustainable Applications of Nanofibers in Agriculture and Water Treatment : A Review ». Sustainability 14, n^o 1 (2 janvier 2022) : 464. http://dx.doi.org/10.3390/su14010464.

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Natural fibers are an important source for producing polymers, which are highly applicable in their nanoform and could be used in very broad fields such as filtration for water/wastewater treatment, biomedicine, food packaging, harvesting, and storage of energy due to their high specific surface area. These natural nanofibers could be mainly produced through plants, animals, and minerals, as well as produced from agricultural wastes. For strengthening these natural fibers, they may reinforce with some substances such as nanomaterials. Natural or biofiber-reinforced bio-composites and nano–bio-composites are considered better than conventional composites. The sustainable application of nanofibers in agricultural sectors is a promising approach and may involve plant protection and its growth through encapsulating many bio-active molecules or agrochemicals (i.e., pesticides, phytohormones, and fertilizers) for smart delivery at the targeted sites. The food industry and processing also are very important applicable fields of nanofibers, particularly food packaging, which may include using nanofibers for active–intelligent food packaging, and food freshness indicators. The removal of pollutants from soil, water, and air is an urgent field for nanofibers due to their high efficiency. Many new approaches or applicable agro-fields for nanofibers are expected in the future, such as using nanofibers as the indicators for CO and NH3. The role of nanofibers in the global fighting against COVID-19 may represent a crucial solution, particularly in producing face masks.

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Rajani, Altaf, Priyanka Chauhan et Pranav Y. Dave. « Nanocomposites : A New Tendency of Structure in Nanotechnology and Material Science ». Journal of Nanoscience and Technology 7, n^o 1 (10 février 2021) : 937–41. http://dx.doi.org/10.30799/jnst.315.21070103.

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Nanoscience has become a diverse and unique field of scientific and technical activity. Over the last few years, the research interest in nanomaterials/nanoparticles and their various applications in various electronic devices, effective optoelectronic devices, bio-sensors, photodetectors, solar cells, nanodevices and plasmonic structures have been increasing tremendously. The reasons are-the unique properties of nanostructures and the outstanding performance of nanoscale devices. At the nanoscale, a material’s property can change dramatically, with unique design possibilities and properties; they attract the attention of researchers worldwide. Nano-composites are those materials with a Nano-scale structure which improves the microscopic property of the products. Composite materials have combinations of two or several nanocomponents, which acquire new and unique characteristic properties that the individual constituents, by themselves, cannot obtain. There are number of various methods to synthesis various Nano-composites. Based on the literature survey, this review article explains a brief introduction of nanocomposites and their types, preparation methods and different diverse properties. It also describes the benefits and limitations of it and new challenges/future scope of the nanocomposites for the better future applications in different sectors.

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Enesca, Alexandru, et Cristina Cazan. « Polymer Composite-Based Materials with Photocatalytic Applications in Wastewater Organic Pollutant Removal : A Mini Review ». Polymers 14, n^o 16 (12 août 2022) : 3291. http://dx.doi.org/10.3390/polym14163291.

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The development of new technologies using nanomaterials has allowed scientists to design advanced processes with many applications in environmental protection, energy production and storage, and medicinal bio-mediated processes. Due to their significant potential applications in different branches of science, the development of new polymer composites represents a priority, especially for nano-technological processes. Interest in polymeric composites was outlined by the synthesis of a large number of nano- or mezzo-scale materials with targeted functional properties for polymer matrix hybridization. The present mini review explores some of the most representative and recent papers reporting the photocatalytic activity of polymer composites toward different organic compounds (dyes, pharmaceutically active molecules, phenol, etc.). The polymer composites were divided based on their composition and photocatalytic activity. TiO2- and ZnO-based polymeric composites have been described here in light of their photocatalytic activity toward different pollutants, such as rhodamine B, phenol, or methyl orange. Polymeric composites based on WO3, Fe2O3, or Bi2MoO6 were also described. The influence of different polymeric composites and photocatalytic parameters (light spectra and intensity, pollutant molecule and concentration, irradiation time, and photocatalyst dosage) on the overall photocatalytic efficiency indicates that semiconductor (TiO2, ZnO, etc.) insertion in the polymeric matrix can tune the photocatalytic activity without compromising the structural integrity. Future perspectives and limitations are outlined considering the systematic and targeted description of the reported results. Adopting green route synthesis and application can add economic and scientific value to the knowledgebase by promoting technological development based on photocatalytic designs.

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Shumyantseva, V. V., T. V. Bulko, A. V. Kuzikov, R. Khan et A. I. Archakov. « Functionalization of screen printed electrodes with organic-inorganic hybrid nano-composites for bio-sensing applications ». Biomeditsinskaya Khimiya 61, n^o 4 (2015) : 474–79. http://dx.doi.org/10.18097/pbmc20156104474.

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New types of organic-inorganic hybrid nanocomposites based on nanosized Titanium (IV) oxide TiO2 (<100 nm particle size) and carbon nanotubes (CNT, outer diameter 10-15 nm, inner diamentre 2-6 nm, length 0.1-10 m) and phosphatidilcholine were elaborated for improvement of analytical characteristics of screen printed electrodes. These nanomaterials were employed as an interface for the immobilization of skeletal myoglobin. Electrochemical behavior of myoglobin on such interfaces was characterized with cyclic voltammetry (CV) and square wave voltammetry (SWV). Direct unmediated electron transfer between myoglobin and electrodes modified with organic-inorganic hybrid nanocomposites was registered. TiO2 film and CNT film are biocompartible nanomaterials for myoglobin as was demonstrated with UV-Vis spectra. The midpoint potential of Fe3+/Fe2+ pair of myoglobin corresponded to Е1/2 = -0,263 V for CNT film, and Е1/2 = -0,468 V for TiO2 nanocomposite (vs. Ag/AgCl reference electrode)

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Mohamed, Abdellatif A., Victoria L. Finkenstadt, Sherald H. Gordon, Mohammed S. Alamri et Shahzad Hussain. « Thermal and Mechanical Properties of Compression-Moulded Poly(Lactic Acid)/Gluten/Clays Bio(Nano)Composites ». Polymers and Polymer Composites 24, n^o 5 (juin 2016) : 375–86. http://dx.doi.org/10.1177/096739111602400508.

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Nygren, Mats, et Zhijian Shen. « On the preparation of bio-, nano- and structural ceramics and composites by spark plasma sintering ». Solid State Sciences 5, n^o 1 (janvier 2003) : 125–31. http://dx.doi.org/10.1016/s1293-2558(02)00086-9.

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Salimi, Kouroush. « Self-assembled bio-inspired Au/CeO2 nano-composites for visible white LED light irradiated photocatalysis ». Colloids and Surfaces A : Physicochemical and Engineering Aspects 599 (août 2020) : 124908. http://dx.doi.org/10.1016/j.colsurfa.2020.124908.

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Kailasanathan, C., N. Selvakumar et Vasant Naidu. « Structure and properties of titania reinforced nano-hydroxyapatite/gelatin bio-composites for bone graft materials ». Ceramics International 38, n^o 1 (janvier 2012) : 571–79. http://dx.doi.org/10.1016/j.ceramint.2011.07.045.

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Joy, Francis, Jyothis Devasia, Aatika Nizam, Vasantha Veerappa Lakshmaiah et Suresh Babu Naidu Krishna. « Fungi-Templated Silver Nanoparticle Composite : Synthesis, Characterization, and Its Applications ». Applied Sciences 13, n^o 4 (8 février 2023) : 2158. http://dx.doi.org/10.3390/app13042158.

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The self-assembly of nanoparticles on living bio-templates is a promising synthetic methodology adopted for synthesizing nano/microstructures with high efficiency. Therefore, the method of bio-templating offers various advantages in controlling the geometries of nano/microstructures, thereby increasing the efficiency of the synthesized material towards various functional applications. Herein, we utilized a filamentous fungus (Sclerotium rolfsii) as a soft bio-template to generate silver nanoparticle (AgNP) microtubules adhering to the fungal hyphae. The resulting composite combines the unique properties of silver nanoparticles with the biological activity of the fungi. The 3D fungal hyphae–silver nanoparticle (FH-AgNP) composite was characterized using SEM, elemental analysis, and the X-ray diffraction technique. Additionally, to highlight the functional application of the synthesized composite, dye degradation studies of methylene blue under visible light was effectuated, and a percentage degradation of 67.86% was obtained within 60 min, which highlights the potent catalytic activity of FH-AgNPs in dye degradation. Further, the antibacterial study of the composite was carried out against the bacterium Escherichia coli, and it was found that 200 μg of the composite exhibited maximum antibacterial properties against Gram positive (Staphylococcus aureus) and Gram negative (Escherichia coli) bacteria. Overall, fungi-templated silver nanoparticle composites are a promising area of research due to their combination of biological activity and unique physical and chemical properties.

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Hosseinpourpia, R., A. Varshoee, M. Soltani, P. Hosseini et H. Ziaei Tabari. « Production of waste bio-fiber cement-based composites reinforced with nano-SiO2 particles as a substitute for asbestos cement composites ». Construction and Building Materials 31 (juin 2012) : 105–11. http://dx.doi.org/10.1016/j.conbuildmat.2011.12.102.

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Yakubu, A. « Microwave Absorption Properties of Unripe Plantain Husk, Polycaprolactone and Charcoal Powder Hybrid Nanocomposites Using Numerical Simulation at X-Band Frequency ». Journal of Nature, Science & ; Technology 1, n^o 2 (19 mars 2021) : 1–6. http://dx.doi.org/10.36937/janset.2021.002.001.

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Single bulk materials have lesser advantages compared to nano materials in the area of mechanical, electrical, dielectric, optical and thermal properties enhancement of polymer and hybrid of bio-composites. In this work, charcoal (CH), unripe plantain husk (UPH), and polycaprolactone (PCL) based microwave absorber were synthesized using both mechanical alloy and melt blend techniques, respectively. Different percentages of the prepared charcoal nanoparticles was introduced into the hybrid composites to study the effect on dielectric properties, shielding effectiveness, reflection loss and structural morphology in the frequency range of 8–12 GHz.. Findings showed that the sample with the highest amount of charcoal percentage had the best shielding effectiveness and dielectric constant. The value of dielectric constant gradually increased from 3.06 to 5.45 at the frequency range measured. The charcoal average particle size was estimated to be 21.42 nm using TEM analysis while the mean deviation of surface roughness ranged from 5.45 to 25.56 nm using atomic force microscope. The highest shielding effectiveness of the hybrid composites was obtained for the 30 wt% nano charcoal content with a value of -48.78 dB at 10 GHz. The complete dispersion and interaction of the charcoal with the PCL and UPH enhanced the dielectric constant, loss factor, hence making it potent in microwave absorption, shielding and radar applications.

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Schmahl, Wolfgang, Erika Griesshaber, Lurdes Fernandez-Diaz, Andreas Ziegler, Klemens Kelm, Bernd Maier, Fitriana Nindiyasari et Guntram Jordan. « Hierarchical structure of CaCO3biominerals – mesocrystals and functionalization ». Acta Crystallographica Section A Foundations and Advances 70, a1 (5 août 2014) : C239. http://dx.doi.org/10.1107/s2053273314097605.

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Skeletal parts and teeth of marine organisms, avian eggshells, trilobite and isopod eyes, and many more biomineralized tissues consist of bio-calcite or bio-aragonite crystals. We explore the nano- to micro-scale architectures of these materials by electron backscatter diffraction (EBSD) and complementary techniques. In contrast to their inorganic cousins the biogenic "crystals" are hybrid composites with small amounts of organic matrix controlling morphogenesis and critically improving mechanical performance or other functions. For the biominerals meso-crystal-like structures are ubiquitous, consisting of co-oriented nano-blocks with a mosaic-spread of a few degrees, depending on the organism and on the size of the mesocrystal entity[1, 2, 3]. The nano-mosaic can be attributed to growth by nano-particle accretion from an amorphous or gel-like precursor, where relics of organic matrix cause misorientations between the crystallized nano-blocks. Recently we were able to reproduce this feature in gel-grown calcite [Nindiyasari et al., Crystal Growth and Design, in press]. The mesocrystal-co-orientation spreads on to the micro- and even millimeter-scale, frequently with a fractal nature of co-oriented hierarchical units [Maier et al., Acta Biomaterialia, accepted for publication]. The hierarchically structured morphology of the composite crystal or polycrystal is always directed by organic matrix membranes. Sea urchin teeth show a multiplex composite crystal architecture, where different subunits of engineered shapes, Mg-contents, and small misalignments are essential prerequisites for self-sharpening [1]. The figure shows an EBSD map of dendritic interdigitating calcite crystals in an avian egg shell (color coding for crystal orientation) with an misorientation profile along the grey line.

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García-Quiles, Lidia, Arantzazu Valdés, Ángel Fernández Cuello, Alfonso Jiménez, María del Carmen Garrigós et Pere Castell. « Reducing off-Flavour in Commercially Available Polyhydroxyalkanoate Materials by Autooxidation through Compounding with Organoclays ». Polymers 11, n^o 6 (31 mai 2019) : 945. http://dx.doi.org/10.3390/polym11060945.

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Polyhydroxyalkanoates (PHAs) are nowadays considered competent candidates to replace traditional plastics in several market sectors. However, commercial PHA materials exhibit unsatisfactory smells that can negatively affect the quality of the final product. The cause of this typical rancid odour is attributed to oxidized cell membrane glycolipids, coming from Gram-negative production strains, which remain frequently attached to PHAs granules after the extraction stage. The aim of this research is the development of customised PHA bio-nano-composites for industrial applications containing organomodified nanoclays with high adsorbance properties able to capture volatile compounds responsible for the displeasing fragrance. To this end, a methodology for the detection and identification of the key volatiles released due to oxidative degradation of PHAs has been established using a headspace solid-phase microextraction technique. We report the development of nine bio-nano-composite materials based on three types of commercial PHA matrices loaded with three species of nanoclays which represent a different polar behaviour. It has been demonstrated that although the reached outcoming effect depends on the volatile nature, natural sepiolite might result in the most versatile candidate for any the PHA matrices selected.

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Kasaai, Mohammad Reza. « Bio-nano-composites containing at least two components, chitosan and zein, for food packaging applications : A review of the nano-composites in comparison with the conventional counterparts ». Carbohydrate Polymers 280 (mars 2022) : 119027. http://dx.doi.org/10.1016/j.carbpol.2021.119027.

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Lei, Gaiying, Shu Yang, Ranran Cao, Peng Zhou, Han Peng, Rui Peng, Xiaoming Zhang et al. « In Situ Preparation of Amphibious ZnO Quantum Dots with Blue Fluorescence Based on Hyperbranched Polymers and their Application in Bio-Imaging ». Polymers 12, n^o 1 (6 janvier 2020) : 144. http://dx.doi.org/10.3390/polym12010144.

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A new strategy for preparing amphibious ZnO quantum dots (QDs) with blue fluorescence within hyper-branched poly(ethylenimine)s (HPEI) was proposed in this paper. By changing [Zn2+]/[OH−] molar ratio and heating time, ZnO QDs with a quantum yields (QY) of 30% in ethanol were obtained. Benefiting from the amphibious property of HPEI, the ZnO/HPEI nanocomposites in ethanol could be dissolved in chloroform and water, acquiring a QY of 53%, chloroform and 11% in water. By this strategy, the ZnO/HPEI nano-composites could be applied in not only in optoelectronics, but also biomedical fields (such as bio-imaging and gene transfection). The bio-imaging application of water-soluble ZnO/HPEI nanocomposites was investigated and it was found that they could easily be endocytosed by the COS-7 cells, without transfection reagent, and they exhibited excellent biological imaging behavior.

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Galimberti, M., V. Barbera, S. Guerra et A. Bernardi. « FACILE FUNCTIONALIZATION OF sp2 CARBON ALLOTROPES WITH A BIOBASED JANUS MOLECULE ». Rubber Chemistry and Technology 90, n^o 2 (1 juin 2017) : 285–307. http://dx.doi.org/10.5254/rct.17.82665.

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ABSTRACT A simple, versatile, sustainable, not expensive method for the functionalization of sp2 carbon allotropes, both nano-sized and nano-structured, without altering their bulk crystalline organization, is presented. Carbon materials available at the commercial scale were used: furnace carbon black (CB), nano-sized graphite with high surface area, and multiwalled carbon nanotubes. A bio-sourced molecule, 2-(2,5-dimethyl-1H-pyrrol-1-yl)-1,3-propanediol (serinol pyrrole), was used for the functionalization. Serinol pyrrole (SP) was obtained from serinol through a reaction with atomic efficiency of about 82%, performed in the absence of solvents or catalysts. Synthesis of serinol pyrrole was performed as well on carbon allotropes as the solid support. Adducts of serinol pyrrole with a carbon allotrope were prepared with the help of either thermal or mechanical energy. Functionalization yield was in all cases larger than 90%. With such adducts, stable dispersions in water and in NR latex were prepared. A few layers of graphene were isolated from the water dispersions, and NR-based composites precipitated from the latex revealed very even distribution of fine graphitic particles. Composites were prepared, based on NR, IR, and BR as the rubbers and CB and silica as the fillers, with different amounts of CB–SP adduct, and were cross-linked with a sulfur-based system without observing appreciable effect of functionalization on vulcanization kinetics. The CB–SP adduct led to appreciable reduction of the Payne effect.

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