The Experts below are selected from a list of 7098 Experts worldwide ranked by ideXlab platform
Yuri Lvov - One of the best experts on this subject based on the ideXlab platform.
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an assembly of organic inorganic composites using Halloysite clay nanotubes
Current Opinion in Colloid and Interface Science, 2018Co-Authors: Giuseppe Lazzara, Yuri Lvov, Anna Stavitskaya, V A Vinokurov, Giuseppe Cavallaro, Abhishek Panchal, Rawil FakhrullinAbstract:Abstract Halloysite is natural tubular clay suitable as a component of biocompatible nanosystems with specific functionalities. The selective modification of Halloysite inner/outer surfaces can be achieved by exploiting supramolecular and covalent interactions resulting in controlled colloidal stability adjusted to the solvent polarity. The functionalized Halloysite nanotubes can be employed as reinforcing filler for polymers as well as carriers for the sustained release of active molecules, such as antioxidants, flame-retardants, corrosion inhibitors, biocides and drugs. The tubular morphology makes Halloysite a perspective template for core-shell metal supports for mesoporous catalysts. The catalysts can be incorporated with selective and unselective metal binding on the nanotubes' outer surface or in the inner lumens. Micropatterns of self-assembled nanotubes have been realized by the droplet casting method. The selective modification of Halloysite has been exploited to increase the nanotubes' ordering in the produced patterns. Pickering emulsions, induced by the self-assembly of Halloysite nanotubes on oil-water interface, can be used for petroleum spill bioremediation and catalysis.
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catalytic cracking of vegetable oils and vacuum gasoil with commercial high alumina zeolite and Halloysite nanotubes for biofuel production
Fuel, 2016Co-Authors: Vagif Abbasov, Yuri Lvov, Tarana Mammadova, Nushabe Aliyeva, Mutallim Abbasov, Nahid Movsumov, Anupam Joshi, Elshad AbdullayevAbstract:Abstract Blends of cottonseed and sunflower oils with vacuum gasoil were catalytically cracked in fixed bed microreactor using commercial high alumina zeolite FCC catalyst and Halloysite nanotubes as a catalyst. Halloysite occurs in nature as clay nanotube with large 5–20 nm inner lumen that provides cost-effective way to produce mesoporous cracking catalysts with low environmental footprint. Performance of the cracking catalyst was significantly improved in terms of gasoline yield and coke formation upon addition of Halloysite. Hydrocarbon content of the gasoline fraction was analyzed in detail and efficiency of the skeletal isomerization within Halloysite pores was observed to be significantly higher than with the FCC catalyst alone, increasing the yield of the branched hydrocarbons in produced gasoline and hence octane rating.
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Halloysite clay nanotubes for loading and sustained release of functional compounds
Advanced Materials, 2016Co-Authors: Yuri Lvov, Wencai Wang, Liqun Zhang, Rawil FakhrullinAbstract:Halloysite is an alumosilicate tubular clay with a diameter of 50 nm, an inner lumen of 15 nm and a length of 600-900 nm. It is a natural biocompatible nanomaterial available in thousands of tons at low price, which makes it a good candidate for nanoarchitectural composites. The inner lumen of Halloysite may be adjusted by etching to 20-30% of the tube volume and loading with functional agents (antioxidants, anticorrosion agents, flame-retardant agents, drugs, or proteins) allowing for formulations with sustained release tuned by the tube end-stoppers for hours and days. Clogging the tube ends in polymeric composites allows further extension of the release time. Thus, antioxidant-loaded Halloysite doped into rubber enhances anti-aging properties for at least 12 months. The addition of 3-5 wt% of Halloysite increases the strength of polymeric materials, and the possibility of the tube's orientation promises a gradient of properties. Halloysite nanotubes are a promising mesoporous media for catalytic nanoparticles that may be seeded on the tube surface or synthesized exclusively in the lumens, providing enhanced catalytic properties, especially at high temperatures. In vitro and in vivo studies on biological cells and worms indicate the safety of Halloysite, and tests for efficient adsorption of mycotoxins in animals' stomachs are also carried out.
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nanotubular Halloysite clay as efficient water filtration system for removal of cationic and anionic dyes
IOP Conference Series: Materials Science and Engineering, 2014Co-Authors: Yafei Zhao, Elshad Abdullayev, Yuri LvovAbstract:Halloysite nanotubes, chemically similar to kaolinite, are formed by rolling of kaolinite layers in tubes with diameter of 50 nm and length of ca. 1 μm. Halloysite has negative SiO2 outermost and positive Al2O3 inner lumen surface, which enables it to be used as potential absorbent for both cationic and anionic dyes due to the efficient bivalent adsorbancy. An adsorption study using cationic Rhodamine 6G and anionic Chrome azurol S has shown approximately two times better dye removal for Halloysite as compared to kaolinite. Halloysite filters have been effectively regenerated up to 50 times by burning the adsorbed dyes. Overall removal efficiency of anionic Chrome azurol S exceeded 99.9% for 5th regeneration cycle of Halloysite. Chrome azurol S adsorption capacity decreases with the increase of ionic strength, temperature and pH. For cationic Rhodamine 6G, higher ionic strength, temperature and initial solution concentration were favorable to enhanced adsorption with optimal pH 8. These results indicate a potential to utilize Halloysite for the removal of ionic dyes from environmental waters.
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enhanced efficiency of antiseptics with sustained release from clay nanotubes
RSC Advances, 2014Co-Authors: Wenbo Wei, Elshad Abdullayev, Rawil Fakhrullin, Renata T Minullina, David K Mills, Yuri LvovAbstract:Natural Halloysite clay tubules were studied for their potential use as miniature biocompatible containers that can be loaded with antiseptics followed by their slow and controlled release. Brilliant green was loaded into 15 nm diameter Halloysite lumen at 15 wt% and provided sustained release over six hours. Formation of a benzotriazole–copper coating on Halloysite nanotubes allowed additional encapsulation providing for more sustained release from 50 to 200 hours. Antibacterial efficiency of the brilliant green in clay nanotubes was tested on Staphylococcus aureus cultures and antibacterial action extended up to 72 hours was demonstrated. Sustained release of amoxicillin and iodine from Halloysite tubes was also demonstrated.
Elshad Abdullayev - One of the best experts on this subject based on the ideXlab platform.
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catalytic cracking of vegetable oils and vacuum gasoil with commercial high alumina zeolite and Halloysite nanotubes for biofuel production
Fuel, 2016Co-Authors: Vagif Abbasov, Yuri Lvov, Tarana Mammadova, Nushabe Aliyeva, Mutallim Abbasov, Nahid Movsumov, Anupam Joshi, Elshad AbdullayevAbstract:Abstract Blends of cottonseed and sunflower oils with vacuum gasoil were catalytically cracked in fixed bed microreactor using commercial high alumina zeolite FCC catalyst and Halloysite nanotubes as a catalyst. Halloysite occurs in nature as clay nanotube with large 5–20 nm inner lumen that provides cost-effective way to produce mesoporous cracking catalysts with low environmental footprint. Performance of the cracking catalyst was significantly improved in terms of gasoline yield and coke formation upon addition of Halloysite. Hydrocarbon content of the gasoline fraction was analyzed in detail and efficiency of the skeletal isomerization within Halloysite pores was observed to be significantly higher than with the FCC catalyst alone, increasing the yield of the branched hydrocarbons in produced gasoline and hence octane rating.
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nanotubular Halloysite clay as efficient water filtration system for removal of cationic and anionic dyes
IOP Conference Series: Materials Science and Engineering, 2014Co-Authors: Yafei Zhao, Elshad Abdullayev, Yuri LvovAbstract:Halloysite nanotubes, chemically similar to kaolinite, are formed by rolling of kaolinite layers in tubes with diameter of 50 nm and length of ca. 1 μm. Halloysite has negative SiO2 outermost and positive Al2O3 inner lumen surface, which enables it to be used as potential absorbent for both cationic and anionic dyes due to the efficient bivalent adsorbancy. An adsorption study using cationic Rhodamine 6G and anionic Chrome azurol S has shown approximately two times better dye removal for Halloysite as compared to kaolinite. Halloysite filters have been effectively regenerated up to 50 times by burning the adsorbed dyes. Overall removal efficiency of anionic Chrome azurol S exceeded 99.9% for 5th regeneration cycle of Halloysite. Chrome azurol S adsorption capacity decreases with the increase of ionic strength, temperature and pH. For cationic Rhodamine 6G, higher ionic strength, temperature and initial solution concentration were favorable to enhanced adsorption with optimal pH 8. These results indicate a potential to utilize Halloysite for the removal of ionic dyes from environmental waters.
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enhanced efficiency of antiseptics with sustained release from clay nanotubes
RSC Advances, 2014Co-Authors: Wenbo Wei, Elshad Abdullayev, Rawil Fakhrullin, Renata T Minullina, David K Mills, Yuri LvovAbstract:Natural Halloysite clay tubules were studied for their potential use as miniature biocompatible containers that can be loaded with antiseptics followed by their slow and controlled release. Brilliant green was loaded into 15 nm diameter Halloysite lumen at 15 wt% and provided sustained release over six hours. Formation of a benzotriazole–copper coating on Halloysite nanotubes allowed additional encapsulation providing for more sustained release from 50 to 200 hours. Antibacterial efficiency of the brilliant green in clay nanotubes was tested on Staphylococcus aureus cultures and antibacterial action extended up to 72 hours was demonstrated. Sustained release of amoxicillin and iodine from Halloysite tubes was also demonstrated.
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functional polymer clay nanotube composites with sustained release of chemical agents
Progress in Polymer Science, 2013Co-Authors: Yuri Lvov, Elshad AbdullayevAbstract:Abstract Natural Halloysite clay nanotubes are described as inorganic reinforcing materials for polymers. Loading these tubes’ 15-nm diameter lumens with chemical agents, including bioactive molecules (self-healing, anticorrosion, antimicrobial agents, proteins, DNA, drugs, etc.), and doping them into polymers allows a controlled sustained release, providing these nanocomposites with new smart properties. Typically, addition of 5% Halloysite synergistically increases polymer strength on 30–70%, enhances composite adhesivity and adds new functions due to triggered release of needed chemicals. Halloysite is biocompatible “green” material and its simple processing combined with low cost make it a perspective additive for polymeric biocomposites. Comparison of Halloysite with other tubule clay – imogolite – is given; these tubes have smaller diameter and much lower loading capacity for macromolecules.
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Halloysite nanotubule clay for efficient water purification
Journal of Colloid and Interface Science, 2013Co-Authors: Yafei Zhao, Elshad Abdullayev, A N Vasiliev, Yuri LvovAbstract:Halloysite clay has chemical structure similar to kaolinite but it is rolled in tubes with diameter of 50 nm and length of ca. 1000 nm. Halloysite exhibits higher adsorption capacity for both cationic and anionic dyes because it has negative SiO2 outermost and positive Al2O3 inner lumen surface; therefore, these clay nanotubes have efficient bivalent adsorbancy. An adsorption study using cationic Rhodamine 6G and anionic Chrome azurol S has shown approximately two times better dye removal for Halloysite as compared to kaolin. Halloysite filters have been effectively regenerated up to 50 times by burning the adsorbed dyes. Overall removal efficiency of anionic Chrome azurol S exceeded 99.9% for 5th regeneration cycle of Halloysite. Chrome azurol S adsorption capacity decreases with the increase of ionic strength, temperature and pH. For cationic Rhodamine 6G, higher ionic strength, temperature and initial solution concentration were favorable to enhanced adsorption with optimal pH 8. The equilibrium adsorption data were described by Langmuir and Freundlich isotherms.
Giuseppe Lazzara - One of the best experts on this subject based on the ideXlab platform.
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polysaccharides Halloysite nanotubes for smart bionanocomposite materials
Carbohydrate Polymers, 2020Co-Authors: Vanessa Bertolino, Stefana Milioto, Giuseppe Cavallaro, Giuseppe LazzaraAbstract:Biopolymers as alternative to fossils-derived polymers are attracting the interest of researcher in material science. Besides the economic advantages, the sustainability makes polysaccharides ideal candidates to prepare films and formulations. The addition of Halloysite nanotubes as green inorganic fillers was exploited to improve the physico-chemical properties and to introduce smart response abilities to the material. Halloysite is a natural tubular nanomaterial with hollow cavity and large aspect ratio. The effect of polymer charge on the morphology and mesoscopic properties of polysaccharides/Halloysite nanocomposites has been highlighted. Different strategies (solvent casting, lyophilization, cryoscopic technique) for the preparation of nanocomposites have been described. In addition, we present novel protocols for the fabrication of polysaccharides/Halloysite nanocomposites suitable as drug delivery systems. The emerging Halloysite-based bionanocomposites are addressed to applications such as biomedicine, packaging, corrosion protection and restoration of cultural heritages. This review provides an overview of the recent progress achieved on Halloysite-polysaccharides nanocomposites.
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Halloysite nanotubes loaded with calcium hydroxide alkaline fillers for the deacidification of waterlogged archeological woods
ACS Applied Materials & Interfaces, 2018Co-Authors: Giuseppe Cavallaro, Stefana Milioto, Filippo Parisi, Giuseppe LazzaraAbstract:A novel green protocol for the deacidifying consolidation of waterlogged archaeological woods through aqueous dispersions of polyethylene glycol (PEG) 1500 and Halloysite nanotubes containing calcium hydroxide has been designed. First, we prepared functionalized Halloysite nanotubes filled with Ca(OH)2 in their lumen. The controlled and sustained release of Ca(OH)2 from the Halloysite lumen extended its neutralization action over time, allowing the development of a long-term deacidification of the wood samples. A preliminary thermomechanical characterization of clay/polymer nanocomposites allows us to determine the experimental conditions to maximize the consolidation efficiency of the wood samples. The penetration of the Halloysite-Ca(OH)2/PEG composite within the wooden pores conferred the robustness of the archaeological woods based on the clay/polymer composition of the consolidant mixture. Compared to the archeological woods treated with pure PEG 1500, the addition of modified nanotubes in the consolidant induced a remarkable improvement in the mechanical performance in terms of flexural strength and rigidity. The pH measurements of the treated woods showed that the Halloysite-Ca(OH)2 are effective alkaline fillers. Accordingly, the modified nanotubes provided a long-term protection for lignin present in the woods that are exposed to artificial aging under acidic atmosphere. The attained knowledge shows that an easy and green protocol for the long-term preservation of wooden artworks can be achieved by the combination of PEG polymers and alkaline tubular nanostructures obtained through the confinement of Ca(OH)2 within the Halloysite cavity.
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Halloysite nanotubes loaded with calcium hydroxide alkaline fillers for the deacidification of waterlogged archeological woods
ACS Applied Materials & Interfaces, 2018Co-Authors: Giuseppe Cavallaro, Stefana Milioto, Filippo Parisi, Giuseppe LazzaraAbstract:A novel green protocol for the deacidifying consolidation of waterlogged archaeological woods through aqueous dispersions of polyethylene glycol (PEG) 1500 and Halloysite nanotubes containing calcium hydroxide has been designed. First, we prepared functionalized Halloysite nanotubes filled with Ca(OH)2 in their lumen. The controlled and sustained release of Ca(OH)2 from the Halloysite lumen extended its neutralization action over time, allowing the development of a long-term deacidification of the wood samples. A preliminary thermomechanical characterization of clay/polymer nanocomposites allows us to determine the experimental conditions to maximize the consolidation efficiency of the wood samples. The penetration of the Halloysite–Ca(OH)2/PEG composite within the wooden pores conferred the robustness of the archaeological woods based on the clay/polymer composition of the consolidant mixture. Compared to the archeological woods treated with pure PEG 1500, the addition of modified nanotubes in the consol...
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an assembly of organic inorganic composites using Halloysite clay nanotubes
Current Opinion in Colloid and Interface Science, 2018Co-Authors: Giuseppe Lazzara, Yuri Lvov, Anna Stavitskaya, V A Vinokurov, Giuseppe Cavallaro, Abhishek Panchal, Rawil FakhrullinAbstract:Abstract Halloysite is natural tubular clay suitable as a component of biocompatible nanosystems with specific functionalities. The selective modification of Halloysite inner/outer surfaces can be achieved by exploiting supramolecular and covalent interactions resulting in controlled colloidal stability adjusted to the solvent polarity. The functionalized Halloysite nanotubes can be employed as reinforcing filler for polymers as well as carriers for the sustained release of active molecules, such as antioxidants, flame-retardants, corrosion inhibitors, biocides and drugs. The tubular morphology makes Halloysite a perspective template for core-shell metal supports for mesoporous catalysts. The catalysts can be incorporated with selective and unselective metal binding on the nanotubes' outer surface or in the inner lumens. Micropatterns of self-assembled nanotubes have been realized by the droplet casting method. The selective modification of Halloysite has been exploited to increase the nanotubes' ordering in the produced patterns. Pickering emulsions, induced by the self-assembly of Halloysite nanotubes on oil-water interface, can be used for petroleum spill bioremediation and catalysis.
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Halloysite Nanotubes Loaded with Calcium Hydroxide: Alkaline Fillers for the Deacidification of Waterlogged Archeological Woods
2018Co-Authors: Giuseppe Cavallaro, Stefana Milioto, Filippo Parisi, Giuseppe LazzaraAbstract:A novel green protocol for the deacidifying consolidation of waterlogged archaeological woods through aqueous dispersions of polyethylene glycol (PEG) 1500 and Halloysite nanotubes containing calcium hydroxide has been designed. First, we prepared functionalized Halloysite nanotubes filled with Ca(OH)2 in their lumen. The controlled and sustained release of Ca(OH)2 from the Halloysite lumen extended its neutralization action over time, allowing the development of a long-term deacidification of the wood samples. A preliminary thermomechanical characterization of clay/polymer nanocomposites allows us to determine the experimental conditions to maximize the consolidation efficiency of the wood samples. The penetration of the Halloysite–Ca(OH)2/PEG composite within the wooden pores conferred the robustness of the archaeological woods based on the clay/polymer composition of the consolidant mixture. Compared to the archeological woods treated with pure PEG 1500, the addition of modified nanotubes in the consolidant induced a remarkable improvement in the mechanical performance in terms of flexural strength and rigidity. The pH measurements of the treated woods showed that the Halloysite–Ca(OH)2 are effective alkaline fillers. Accordingly, the modified nanotubes provided a long-term protection for lignin present in the woods that are exposed to artificial aging under acidic atmosphere. The attained knowledge shows that an easy and green protocol for the long-term preservation of wooden artworks can be achieved by the combination of PEG polymers and alkaline tubular nanostructures obtained through the confinement of Ca(OH)2 within the Halloysite cavity
Giuseppe Cavallaro - One of the best experts on this subject based on the ideXlab platform.
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polysaccharides Halloysite nanotubes for smart bionanocomposite materials
Carbohydrate Polymers, 2020Co-Authors: Vanessa Bertolino, Stefana Milioto, Giuseppe Cavallaro, Giuseppe LazzaraAbstract:Biopolymers as alternative to fossils-derived polymers are attracting the interest of researcher in material science. Besides the economic advantages, the sustainability makes polysaccharides ideal candidates to prepare films and formulations. The addition of Halloysite nanotubes as green inorganic fillers was exploited to improve the physico-chemical properties and to introduce smart response abilities to the material. Halloysite is a natural tubular nanomaterial with hollow cavity and large aspect ratio. The effect of polymer charge on the morphology and mesoscopic properties of polysaccharides/Halloysite nanocomposites has been highlighted. Different strategies (solvent casting, lyophilization, cryoscopic technique) for the preparation of nanocomposites have been described. In addition, we present novel protocols for the fabrication of polysaccharides/Halloysite nanocomposites suitable as drug delivery systems. The emerging Halloysite-based bionanocomposites are addressed to applications such as biomedicine, packaging, corrosion protection and restoration of cultural heritages. This review provides an overview of the recent progress achieved on Halloysite-polysaccharides nanocomposites.
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Halloysite nanotubes loaded with calcium hydroxide alkaline fillers for the deacidification of waterlogged archeological woods
ACS Applied Materials & Interfaces, 2018Co-Authors: Giuseppe Cavallaro, Stefana Milioto, Filippo Parisi, Giuseppe LazzaraAbstract:A novel green protocol for the deacidifying consolidation of waterlogged archaeological woods through aqueous dispersions of polyethylene glycol (PEG) 1500 and Halloysite nanotubes containing calcium hydroxide has been designed. First, we prepared functionalized Halloysite nanotubes filled with Ca(OH)2 in their lumen. The controlled and sustained release of Ca(OH)2 from the Halloysite lumen extended its neutralization action over time, allowing the development of a long-term deacidification of the wood samples. A preliminary thermomechanical characterization of clay/polymer nanocomposites allows us to determine the experimental conditions to maximize the consolidation efficiency of the wood samples. The penetration of the Halloysite-Ca(OH)2/PEG composite within the wooden pores conferred the robustness of the archaeological woods based on the clay/polymer composition of the consolidant mixture. Compared to the archeological woods treated with pure PEG 1500, the addition of modified nanotubes in the consolidant induced a remarkable improvement in the mechanical performance in terms of flexural strength and rigidity. The pH measurements of the treated woods showed that the Halloysite-Ca(OH)2 are effective alkaline fillers. Accordingly, the modified nanotubes provided a long-term protection for lignin present in the woods that are exposed to artificial aging under acidic atmosphere. The attained knowledge shows that an easy and green protocol for the long-term preservation of wooden artworks can be achieved by the combination of PEG polymers and alkaline tubular nanostructures obtained through the confinement of Ca(OH)2 within the Halloysite cavity.
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Halloysite nanotubes loaded with calcium hydroxide alkaline fillers for the deacidification of waterlogged archeological woods
ACS Applied Materials & Interfaces, 2018Co-Authors: Giuseppe Cavallaro, Stefana Milioto, Filippo Parisi, Giuseppe LazzaraAbstract:A novel green protocol for the deacidifying consolidation of waterlogged archaeological woods through aqueous dispersions of polyethylene glycol (PEG) 1500 and Halloysite nanotubes containing calcium hydroxide has been designed. First, we prepared functionalized Halloysite nanotubes filled with Ca(OH)2 in their lumen. The controlled and sustained release of Ca(OH)2 from the Halloysite lumen extended its neutralization action over time, allowing the development of a long-term deacidification of the wood samples. A preliminary thermomechanical characterization of clay/polymer nanocomposites allows us to determine the experimental conditions to maximize the consolidation efficiency of the wood samples. The penetration of the Halloysite–Ca(OH)2/PEG composite within the wooden pores conferred the robustness of the archaeological woods based on the clay/polymer composition of the consolidant mixture. Compared to the archeological woods treated with pure PEG 1500, the addition of modified nanotubes in the consol...
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an assembly of organic inorganic composites using Halloysite clay nanotubes
Current Opinion in Colloid and Interface Science, 2018Co-Authors: Giuseppe Lazzara, Yuri Lvov, Anna Stavitskaya, V A Vinokurov, Giuseppe Cavallaro, Abhishek Panchal, Rawil FakhrullinAbstract:Abstract Halloysite is natural tubular clay suitable as a component of biocompatible nanosystems with specific functionalities. The selective modification of Halloysite inner/outer surfaces can be achieved by exploiting supramolecular and covalent interactions resulting in controlled colloidal stability adjusted to the solvent polarity. The functionalized Halloysite nanotubes can be employed as reinforcing filler for polymers as well as carriers for the sustained release of active molecules, such as antioxidants, flame-retardants, corrosion inhibitors, biocides and drugs. The tubular morphology makes Halloysite a perspective template for core-shell metal supports for mesoporous catalysts. The catalysts can be incorporated with selective and unselective metal binding on the nanotubes' outer surface or in the inner lumens. Micropatterns of self-assembled nanotubes have been realized by the droplet casting method. The selective modification of Halloysite has been exploited to increase the nanotubes' ordering in the produced patterns. Pickering emulsions, induced by the self-assembly of Halloysite nanotubes on oil-water interface, can be used for petroleum spill bioremediation and catalysis.
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Halloysite Nanotubes Loaded with Calcium Hydroxide: Alkaline Fillers for the Deacidification of Waterlogged Archeological Woods
2018Co-Authors: Giuseppe Cavallaro, Stefana Milioto, Filippo Parisi, Giuseppe LazzaraAbstract:A novel green protocol for the deacidifying consolidation of waterlogged archaeological woods through aqueous dispersions of polyethylene glycol (PEG) 1500 and Halloysite nanotubes containing calcium hydroxide has been designed. First, we prepared functionalized Halloysite nanotubes filled with Ca(OH)2 in their lumen. The controlled and sustained release of Ca(OH)2 from the Halloysite lumen extended its neutralization action over time, allowing the development of a long-term deacidification of the wood samples. A preliminary thermomechanical characterization of clay/polymer nanocomposites allows us to determine the experimental conditions to maximize the consolidation efficiency of the wood samples. The penetration of the Halloysite–Ca(OH)2/PEG composite within the wooden pores conferred the robustness of the archaeological woods based on the clay/polymer composition of the consolidant mixture. Compared to the archeological woods treated with pure PEG 1500, the addition of modified nanotubes in the consolidant induced a remarkable improvement in the mechanical performance in terms of flexural strength and rigidity. The pH measurements of the treated woods showed that the Halloysite–Ca(OH)2 are effective alkaline fillers. Accordingly, the modified nanotubes provided a long-term protection for lignin present in the woods that are exposed to artificial aging under acidic atmosphere. The attained knowledge shows that an easy and green protocol for the long-term preservation of wooden artworks can be achieved by the combination of PEG polymers and alkaline tubular nanostructures obtained through the confinement of Ca(OH)2 within the Halloysite cavity
Stefana Milioto - One of the best experts on this subject based on the ideXlab platform.
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polysaccharides Halloysite nanotubes for smart bionanocomposite materials
Carbohydrate Polymers, 2020Co-Authors: Vanessa Bertolino, Stefana Milioto, Giuseppe Cavallaro, Giuseppe LazzaraAbstract:Biopolymers as alternative to fossils-derived polymers are attracting the interest of researcher in material science. Besides the economic advantages, the sustainability makes polysaccharides ideal candidates to prepare films and formulations. The addition of Halloysite nanotubes as green inorganic fillers was exploited to improve the physico-chemical properties and to introduce smart response abilities to the material. Halloysite is a natural tubular nanomaterial with hollow cavity and large aspect ratio. The effect of polymer charge on the morphology and mesoscopic properties of polysaccharides/Halloysite nanocomposites has been highlighted. Different strategies (solvent casting, lyophilization, cryoscopic technique) for the preparation of nanocomposites have been described. In addition, we present novel protocols for the fabrication of polysaccharides/Halloysite nanocomposites suitable as drug delivery systems. The emerging Halloysite-based bionanocomposites are addressed to applications such as biomedicine, packaging, corrosion protection and restoration of cultural heritages. This review provides an overview of the recent progress achieved on Halloysite-polysaccharides nanocomposites.
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Halloysite nanotubes loaded with calcium hydroxide alkaline fillers for the deacidification of waterlogged archeological woods
ACS Applied Materials & Interfaces, 2018Co-Authors: Giuseppe Cavallaro, Stefana Milioto, Filippo Parisi, Giuseppe LazzaraAbstract:A novel green protocol for the deacidifying consolidation of waterlogged archaeological woods through aqueous dispersions of polyethylene glycol (PEG) 1500 and Halloysite nanotubes containing calcium hydroxide has been designed. First, we prepared functionalized Halloysite nanotubes filled with Ca(OH)2 in their lumen. The controlled and sustained release of Ca(OH)2 from the Halloysite lumen extended its neutralization action over time, allowing the development of a long-term deacidification of the wood samples. A preliminary thermomechanical characterization of clay/polymer nanocomposites allows us to determine the experimental conditions to maximize the consolidation efficiency of the wood samples. The penetration of the Halloysite-Ca(OH)2/PEG composite within the wooden pores conferred the robustness of the archaeological woods based on the clay/polymer composition of the consolidant mixture. Compared to the archeological woods treated with pure PEG 1500, the addition of modified nanotubes in the consolidant induced a remarkable improvement in the mechanical performance in terms of flexural strength and rigidity. The pH measurements of the treated woods showed that the Halloysite-Ca(OH)2 are effective alkaline fillers. Accordingly, the modified nanotubes provided a long-term protection for lignin present in the woods that are exposed to artificial aging under acidic atmosphere. The attained knowledge shows that an easy and green protocol for the long-term preservation of wooden artworks can be achieved by the combination of PEG polymers and alkaline tubular nanostructures obtained through the confinement of Ca(OH)2 within the Halloysite cavity.
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Halloysite nanotubes loaded with calcium hydroxide alkaline fillers for the deacidification of waterlogged archeological woods
ACS Applied Materials & Interfaces, 2018Co-Authors: Giuseppe Cavallaro, Stefana Milioto, Filippo Parisi, Giuseppe LazzaraAbstract:A novel green protocol for the deacidifying consolidation of waterlogged archaeological woods through aqueous dispersions of polyethylene glycol (PEG) 1500 and Halloysite nanotubes containing calcium hydroxide has been designed. First, we prepared functionalized Halloysite nanotubes filled with Ca(OH)2 in their lumen. The controlled and sustained release of Ca(OH)2 from the Halloysite lumen extended its neutralization action over time, allowing the development of a long-term deacidification of the wood samples. A preliminary thermomechanical characterization of clay/polymer nanocomposites allows us to determine the experimental conditions to maximize the consolidation efficiency of the wood samples. The penetration of the Halloysite–Ca(OH)2/PEG composite within the wooden pores conferred the robustness of the archaeological woods based on the clay/polymer composition of the consolidant mixture. Compared to the archeological woods treated with pure PEG 1500, the addition of modified nanotubes in the consol...
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Halloysite Nanotubes Loaded with Calcium Hydroxide: Alkaline Fillers for the Deacidification of Waterlogged Archeological Woods
2018Co-Authors: Giuseppe Cavallaro, Stefana Milioto, Filippo Parisi, Giuseppe LazzaraAbstract:A novel green protocol for the deacidifying consolidation of waterlogged archaeological woods through aqueous dispersions of polyethylene glycol (PEG) 1500 and Halloysite nanotubes containing calcium hydroxide has been designed. First, we prepared functionalized Halloysite nanotubes filled with Ca(OH)2 in their lumen. The controlled and sustained release of Ca(OH)2 from the Halloysite lumen extended its neutralization action over time, allowing the development of a long-term deacidification of the wood samples. A preliminary thermomechanical characterization of clay/polymer nanocomposites allows us to determine the experimental conditions to maximize the consolidation efficiency of the wood samples. The penetration of the Halloysite–Ca(OH)2/PEG composite within the wooden pores conferred the robustness of the archaeological woods based on the clay/polymer composition of the consolidant mixture. Compared to the archeological woods treated with pure PEG 1500, the addition of modified nanotubes in the consolidant induced a remarkable improvement in the mechanical performance in terms of flexural strength and rigidity. The pH measurements of the treated woods showed that the Halloysite–Ca(OH)2 are effective alkaline fillers. Accordingly, the modified nanotubes provided a long-term protection for lignin present in the woods that are exposed to artificial aging under acidic atmosphere. The attained knowledge shows that an easy and green protocol for the long-term preservation of wooden artworks can be achieved by the combination of PEG polymers and alkaline tubular nanostructures obtained through the confinement of Ca(OH)2 within the Halloysite cavity
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effect of morphology and size of Halloysite nanotubes on functional pectin bionanocomposites for food packaging applications
ACS Applied Materials & Interfaces, 2017Co-Authors: Maziyar Makaremi, Pooria Pasbakhsh, Giuseppe Lazzara, Giuseppe Cavallaro, Sui Mae Lee, Yoong Kit Aw, Stefana MiliotoAbstract:Pectin bionanocomposite films filled with various concentrations of two different types of Halloysite nanotubes were prepared and characterized in this study as potential films for food packaging applications. The two types of Halloysite nanotubes were long and thin (patch) (200–30 000 nm length) and short and stubby (Matauri Bay) (50–3000 nm length) with different morphological, physical, and dispersibility properties. Both matrix (pectin) and reinforcer (Halloysite nanotubes) used in this study are considered as biocompatible, natural, and low-cost materials. Various characterization tests including Fourier transform infrared spectroscopy, field emission scanning electron microscopy, release kinetics, contact angle, and dynamic mechanical analysis were performed to evaluate the performance of the pectin films. Exceptional thermal, tensile, and contact angle properties have been achieved for films reinforced by patch Halloysite nanotubes due to the patchy and lengthy nature of these tubes, which form a b...
