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Liu X, Zhang L, Zhang Q, Li M, Zhao Z, Lin B, Peng J, Shen H, He Q. Fenton-like system of UV/Glucose-oxidase@Kaolin coupled with organic green rust: UV-enhanced enzyme activity and the mechanism of UV synergistic degradation of photosensitive pollutants. ENVIRONMENTAL RESEARCH 2024; 247:118257. [PMID: 38262511 DOI: 10.1016/j.envres.2024.118257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2023] [Revised: 01/10/2024] [Accepted: 01/17/2024] [Indexed: 01/25/2024]
Abstract
This study introduces the UV/glucose-oxidase@Kaolin (GOD@Kaolin) coupled organic green rust (OGR) system (UV/OGR/GOD@Kaolin) to investigate the promotion of glucose oxidase activity by UV light and its synergistic degradation mechanism for photosensitive pollutants, specifically targeting the efficient degradation of 4-chlorophenol (4-CP). The enzyme system demonstrates its ability to overcome drawbacks associated with traditional Fenton systems, including a narrow pH range and high localized concentration of H2O2, by gradually releasing hydrogen peroxide in situ within a neutral environment. In the presence of UV radiation under specific conditions, enhanced enzyme activity is observed, resulting in increased efficiency in pollutant removal. The gradual release of hydrogen peroxide plays a crucial role in preventing unwanted reactions among active substances. These unique features facilitate the generation of highly reactive species, such as Fe(IV)O, •OH, and •O2-, tailored to efficiently target the organic components of interest. Additionally, the system establishes a positive iron cycle, ensuring a sustained reactive capability throughout the degradation process. The results highlight the UV/OGR/GOD@Kaolin system as an effective and environmentally friendly approach for the degradation of 4-CP, and the resilience of the enzyme extends the system's applicability to a broader range of scenarios.
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Affiliation(s)
- Xiangyu Liu
- School of Civil Engineering & Architecture, Wuhan University of Technology, 122 Luoshi Road, Wuhan, 430070, China
| | - Lei Zhang
- MWR Standard & Quality Control Research Institute, Hangzhou, 310024, China
| | - Qian Zhang
- School of Civil Engineering & Architecture, Wuhan University of Technology, 122 Luoshi Road, Wuhan, 430070, China; Shenzhen Research Institute of Wuhan University of Technology, Shenzhen, 518000, China.
| | - Meng Li
- School of Civil Engineering & Architecture, Wuhan University of Technology, 122 Luoshi Road, Wuhan, 430070, China; Shenzhen Research Institute of Wuhan University of Technology, Shenzhen, 518000, China
| | - Ziqi Zhao
- Wuhan HUADET Environmental Protection Engineering & Technology, Wuhan, 430080, China
| | - Bing Lin
- School of Civil Engineering & Architecture, Wuhan University of Technology, 122 Luoshi Road, Wuhan, 430070, China
| | - Jie Peng
- School of Civil Engineering & Architecture, Wuhan University of Technology, 122 Luoshi Road, Wuhan, 430070, China
| | - Haonan Shen
- School of Civil Engineering & Architecture, Wuhan University of Technology, 122 Luoshi Road, Wuhan, 430070, China
| | - Qi He
- School of Civil Engineering & Architecture, Wuhan University of Technology, 122 Luoshi Road, Wuhan, 430070, China
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Alam MN, Kumar V, Jeong SU, Park SS. Enhancing Rubber Vulcanization Cure Kinetics: Lowering Vulcanization Temperature by Addition of MgO as Co-Cure Activator in ZnO-Based Cure Activator Systems. Polymers (Basel) 2024; 16:876. [PMID: 38611134 PMCID: PMC11013655 DOI: 10.3390/polym16070876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Revised: 03/09/2024] [Accepted: 03/21/2024] [Indexed: 04/14/2024] Open
Abstract
Vulcanization is a chemical modification of rubber that requires a considerable amount of thermal energy. To save thermal energy, the kinetics of rubber vulcanization should be improved. In this article, the curing properties of rubber vulcanization are thoroughly investigated using the moving die rheometer (MDR) technique. To enhance the kinetics in different stages of ZnO-based sulfur vulcanization systems, small amounts of MgO were added. The results revealed that the small amount of 1 to 2 phr (per hundred grams of rubber) of MgO in the controlled 5 phr ZnO-based curing systems can significantly improve the curing kinetics. For example, the optimum curing time of 1 phr MgO added to the 5 phr ZnO-containing semi-efficient vulcanization system at different temperatures was more than half that of the controlled 5 phr ZnO-only compound. While maintaining a similar rate of vulcanization, the vulcanization temperature can be reduced by up to 20 °C by using MgO as a co-cure activator, which exhibits similar or better rheometric mechanical properties compared to the controlled compounds. With the addition of MgO as a co-cure activator, the vulcanization reactions become very fast, enabling vulcanization to be completed, even at the boiling point of water (100 °C) with an affordable curing time (<1 h). By reducing the vulcanization temperature, the scorch safety time can be enhanced in the ZnO/MgO-based binary cure activator-containing vulcanizates. Overall, MgO could be a potential candidate as a co-cure activator with ZnO for the vulcanization of rubber, offering better economical and eco-friendly methods.
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Affiliation(s)
- Md Najib Alam
- School of Mechanical Engineering, Yeungnam University, 280, Daehak-ro, Gyeongsan 38541, Republic of Korea; (M.N.A.); (V.K.)
| | - Vineet Kumar
- School of Mechanical Engineering, Yeungnam University, 280, Daehak-ro, Gyeongsan 38541, Republic of Korea; (M.N.A.); (V.K.)
| | - Seok U Jeong
- Graduate School of Mechanical Engineering, Yeungnam University, 280, Daehak-ro, Gyeongsan 38541, Republic of Korea;
| | - Sang-Shin Park
- School of Mechanical Engineering, Yeungnam University, 280, Daehak-ro, Gyeongsan 38541, Republic of Korea; (M.N.A.); (V.K.)
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Jiang Y, Shen Z, Tang CS, Shi B. Synthesis and application of waste-based layered double hydroxide: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 903:166245. [PMID: 37579803 DOI: 10.1016/j.scitotenv.2023.166245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 07/23/2023] [Accepted: 08/10/2023] [Indexed: 08/16/2023]
Abstract
The synthesis of layered double hydroxide (LDH) from industrial wastes is a sustainable approach to aid circular economy and hazardous material disposal. In this review, the researches on the synthesis and application of waste-based LDH from 2010 to 2023 are summarized and discussed. At present, there are mainly four types of waste-based LDH produced from red mud, slag, fly ash and wastewater, with co-precipitation being the most typical synthesis method. Red mud is used as the trivalent metal source supplemented by chemical reagents or other types of waste as divalent metal source to produce red mud-based LDH. Slag can act as the sole metal source providing both divalent and trivalent metal sources for slag-based LDH. Fly ash was used either as the trivalent metal source or both divalent and trivalent metal sources to produce fly ash-based LDH. Wastewater-based LDH was typically synthesized by in-situ co-precipitation method to achieve the self-purification of wastewater. The impurities in waste-based LDH can act as a two-edged weapon. It may either hinder or promote the performance of waste-based LDH. The challenge in the synthesis of waste-based LDH lies in the efficient extraction of available metals. The future research prospects for waste-based LDH are suggested.
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Affiliation(s)
- Yimei Jiang
- School of Earth Sciences and Engineering, Nanjing University, Nanjing 210023, China
| | - Zhengtao Shen
- School of Earth Sciences and Engineering, Nanjing University, Nanjing 210023, China.
| | - Chao-Sheng Tang
- School of Earth Sciences and Engineering, Nanjing University, Nanjing 210023, China
| | - Bin Shi
- School of Earth Sciences and Engineering, Nanjing University, Nanjing 210023, China
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de Macêdo Neto JC, de Freitas BM, de Miranda AG, de Almeida Rodrigues R, Del Pino GG, Kieling AC, Dos Santos MD, Duvoisin Junior S, Sanches AE, Gondres Torné I, Silva CC, da Costa JCM, Bello RH. The Stability and Properties of Polystyrene/Kaolinite Nanocomposites during Synthesis via Emulsion Polymerization. Polymers (Basel) 2023; 15:polym15092094. [PMID: 37177240 PMCID: PMC10180905 DOI: 10.3390/polym15092094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 02/19/2023] [Accepted: 04/25/2023] [Indexed: 05/15/2023] Open
Abstract
The aim of this work was to study the stability and morphological properties of polystyrene latex containing kaolinite as a filler during the process of synthesis of nanocomposites viaemulsion polymerization. Nanocomposites with 1, 3, and 5 wt% of kaolinite were prepared. Latexes with 1 to 3 wt% of kaolinite were stable during the polymerization reaction. Hydrodynamic diameters of 93.68 and 82.11 nm were found for latexes with 1 and 3 wt% of kaolinite, respectively. The quantities of 1 to 3 wt% of kaolinite added during the reaction did not influence the reaction conversion curves or the number of particles. X-ray diffraction (XRD) and unconventional techniques of scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM) showed the presence of exfoliated and intercalated structures of the kaolinite.
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Affiliation(s)
- José Costa de Macêdo Neto
- Department of Materials Engineering, School of Engineering, Amazonas State University, Avenida Darcy Vargas, 1200, Parque Dez de Novembro, Manaus 69850-000, AM, Brazil
| | - Bruno Mello de Freitas
- Department of Materials Engineering, School of Engineering, Amazonas State University, Avenida Darcy Vargas, 1200, Parque Dez de Novembro, Manaus 69850-000, AM, Brazil
| | - Adalberto Gomes de Miranda
- Department of Materials Engineering, School of Engineering, Amazonas State University, Avenida Darcy Vargas, 1200, Parque Dez de Novembro, Manaus 69850-000, AM, Brazil
| | - Reinaldo de Almeida Rodrigues
- Department of Materials Engineering, School of Engineering, Amazonas State University, Avenida Darcy Vargas, 1200, Parque Dez de Novembro, Manaus 69850-000, AM, Brazil
| | - Gilberto Garcia Del Pino
- Department of Materials Engineering, School of Engineering, Amazonas State University, Avenida Darcy Vargas, 1200, Parque Dez de Novembro, Manaus 69850-000, AM, Brazil
| | - Antônio Claudio Kieling
- Department of Materials Engineering, School of Engineering, Amazonas State University, Avenida Darcy Vargas, 1200, Parque Dez de Novembro, Manaus 69850-000, AM, Brazil
| | - Marcos Dantas Dos Santos
- Department of Materials Engineering, School of Engineering, Amazonas State University, Avenida Darcy Vargas, 1200, Parque Dez de Novembro, Manaus 69850-000, AM, Brazil
| | - Sergio Duvoisin Junior
- Department of Materials Engineering, School of Engineering, Amazonas State University, Avenida Darcy Vargas, 1200, Parque Dez de Novembro, Manaus 69850-000, AM, Brazil
| | - Antônio Estanislau Sanches
- Department of Materials Engineering, School of Engineering, Amazonas State University, Avenida Darcy Vargas, 1200, Parque Dez de Novembro, Manaus 69850-000, AM, Brazil
| | - Israel Gondres Torné
- Department of Materials Engineering, School of Engineering, Amazonas State University, Avenida Darcy Vargas, 1200, Parque Dez de Novembro, Manaus 69850-000, AM, Brazil
| | - Cláudia Cândida Silva
- Department of Materials Engineering, School of Engineering, Amazonas State University, Avenida Darcy Vargas, 1200, Parque Dez de Novembro, Manaus 69850-000, AM, Brazil
| | - João Carlos Martins da Costa
- Department of Materials Engineering, School of Engineering, Amazonas State University, Avenida Darcy Vargas, 1200, Parque Dez de Novembro, Manaus 69850-000, AM, Brazil
| | - Roger Hoel Bello
- Department of Materials Engineering, School of Engineering, Amazonas State University, Avenida Darcy Vargas, 1200, Parque Dez de Novembro, Manaus 69850-000, AM, Brazil
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Wu J, Yin J, Hu J, Wang Q, Zhang H, Xin R, Wang S, Yan S, Zhang J. Strain-induced 3D-oriented crystallites in natural rubber/chitin nanofiber composites. SOFT MATTER 2023; 19:2932-2940. [PMID: 37013408 DOI: 10.1039/d3sm00022b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Natural rubber (NR) composites containing bio-based chitin nanofibers (ChNFs) exhibit a wide range of mechanical properties - from rubber to plastic behavior - with increasing chitin contents. A constrained 3-dimensional network can be formed by mixing natural rubber latex and a modified zwitterionic rigid chitin counterpart. By inclusion of highly anisotropic chitin nanofibers (30 wt%), strain-induced NR crystallization occurs at a much lower strain of 50%. More intriguingly, 2D-WAXD results reveal that the strain-induced crystallization of NR/ChNFs composites show 3-dimensionally oriented crystallite formation behaving similar to "3D-single crystals orientation" when the content of ChNFs is over 5 wt%. It is suggested that not only c-axis (NR chains) orients along the stretching direction, but also the a- and b-axes deliberately arrange along the normal direction and transverse direction, respectively. Structure and morphology in 3-dimensional spaces after strain-induced crystallization of the NR/ChNFs30 composite are investigated in detail. Therefore, this study might pave a new way to enhance mechanical properties by incorporation of ChNFs, obtaining 3-dimensionally oriented crystallites of novel multifunctional NR/ChNFs composite with shape memory ability.
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Affiliation(s)
- Jinghua Wu
- Key Laboratory of Rubber-Plastics, Ministry of Education/Shandong Provincial Key Laboratory of Rubber-Plastics, Qingdao University of Science & Technology, Qingdao City 266042, P. R. China.
| | - Jin Yin
- Key Laboratory of Rubber-Plastics, Ministry of Education/Shandong Provincial Key Laboratory of Rubber-Plastics, Qingdao University of Science & Technology, Qingdao City 266042, P. R. China.
| | - Jian Hu
- Key Laboratory of Rubber-Plastics, Ministry of Education/Shandong Provincial Key Laboratory of Rubber-Plastics, Qingdao University of Science & Technology, Qingdao City 266042, P. R. China.
| | - Qiran Wang
- Key Laboratory of Rubber-Plastics, Ministry of Education/Shandong Provincial Key Laboratory of Rubber-Plastics, Qingdao University of Science & Technology, Qingdao City 266042, P. R. China.
| | - Hao Zhang
- Key Laboratory of Rubber-Plastics, Ministry of Education/Shandong Provincial Key Laboratory of Rubber-Plastics, Qingdao University of Science & Technology, Qingdao City 266042, P. R. China.
| | - Rui Xin
- Key Laboratory of Rubber-Plastics, Ministry of Education/Shandong Provincial Key Laboratory of Rubber-Plastics, Qingdao University of Science & Technology, Qingdao City 266042, P. R. China.
| | - Shaojuan Wang
- Key Laboratory of Rubber-Plastics, Ministry of Education/Shandong Provincial Key Laboratory of Rubber-Plastics, Qingdao University of Science & Technology, Qingdao City 266042, P. R. China.
| | - Shouke Yan
- Key Laboratory of Rubber-Plastics, Ministry of Education/Shandong Provincial Key Laboratory of Rubber-Plastics, Qingdao University of Science & Technology, Qingdao City 266042, P. R. China.
- State Key Laboratory of Chemical Resource Engineering, College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, P. R. China
| | - Jianming Zhang
- Key Laboratory of Rubber-Plastics, Ministry of Education/Shandong Provincial Key Laboratory of Rubber-Plastics, Qingdao University of Science & Technology, Qingdao City 266042, P. R. China.
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6
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Jie Z, Yichen J, Ping L, Yang L, Huiyuan T, Xiuhong D, Zehua W, Xianying D, Chunguang L, Jiehu C. Rational construction and understanding the effect of metal cation substitution of three novel ternary Zn-Co-Ni-LDHs from 2D to 3D and its enhanced adsorption properties for MO. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:3383-3401. [PMID: 35945322 DOI: 10.1007/s11356-022-22303-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Accepted: 07/26/2022] [Indexed: 06/15/2023]
Abstract
The layered double hydroxides (LDHs) have attracted attention in the water treatment field. In this paper, three novel ternary Zn-Co-Ni-LDH adsorbents were prepared successfully through rational construction from 2D to 3D using triethanolamine (TEA) as an alkali source and a structural controlling reagent by hydrothermal technique. Samples were characterized by the SEM, XRD, XPS, FTIR, BET, solid-state UV/vis spectra, and TG. Three Zn-Co-Ni-LDHs exhibited higher crystallinity and surface area which were beneficial to the adsorption for methyl orange (MO). The maximum adsorption capacity of three Zn-Co-Ni-LDH adsorbents can even reach as high as 1871.65 mg·g-1, 1799.56 mg·g-1, and 1646.44 mg·g-1 for MO, respectively, which surpass those of most previously reported LDH-based adsorbents. The pseudo-second-order kinetic equation fitted the kinetic data of adsorption, while the equilibrium adsorption isotherm data followed the Langmuir model. The adsorption mechanism, electrochemical, and the antibacterial properties of three Zn-Co-Ni-LDHs were also discussed. This results not only demonstrates that three Zn-Co-Ni-LDHs are practical interest as an efficient adsorbent for the removal of MO from dye waste water, but also provides a strategy for the rational design through three ternary Zn-Co-Ni-LDHs from 2D to 3D.
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Affiliation(s)
- Zhu Jie
- School of Materials Science and Engineering, Zhengzhou University of Aeronautics, Zhengzhou, People's Republic of China
| | - Jiang Yichen
- School of Materials Science and Engineering, Zhengzhou University of Aeronautics, Zhengzhou, People's Republic of China
| | - Li Ping
- School of Materials Science and Engineering, Zhengzhou University of Aeronautics, Zhengzhou, People's Republic of China
| | - Li Yang
- School of Materials Science and Engineering, Zhengzhou University of Aeronautics, Zhengzhou, People's Republic of China
| | - Tian Huiyuan
- School of Materials Science and Engineering, Zhengzhou University of Aeronautics, Zhengzhou, People's Republic of China
| | - Du Xiuhong
- Clinical Laboratory Medicine, Henan Medical College, Zhengzhou, People's Republic of China
| | - Wang Zehua
- School of Materials Science and Engineering, Zhengzhou University of Aeronautics, Zhengzhou, People's Republic of China
| | - Duan Xianying
- School of Medicine, Huanghe Science and Technology University, Zhengzhou, People's Republic of China
- Institute of Chemistry, Henan Academy of Sciences, Zhengzhou, Henan, 450002, People's Republic of China
| | - Li Chunguang
- School of Materials Science and Engineering, Zhengzhou University of Aeronautics, Zhengzhou, People's Republic of China
| | - Cui Jiehu
- School of Materials Science and Engineering, Zhengzhou University of Aeronautics, Zhengzhou, People's Republic of China.
- Henan Key Laboratory of Aeronautical Material and Application Technology, Zhengzhou University of Aeronautics, Zhengzhou, People's Republic of China.
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Advances in Rubber Compounds Using ZnO and MgO as Co-Cure Activators. Polymers (Basel) 2022; 14:polym14235289. [PMID: 36501682 PMCID: PMC9737580 DOI: 10.3390/polym14235289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 11/30/2022] [Accepted: 12/02/2022] [Indexed: 12/09/2022] Open
Abstract
Zinc oxide performs as the best cure activator in sulfur-based vulcanization of rubber, but it is regarded as a highly toxic material for aquatic organisms. Hence, the toxic cure activator should be replaced by a non-toxic one. Still, there is no suitable alternative industrially. However, binary activators combining ZnO and another metal oxide such as MgO can largely reduce the level of ZnO with some improved benefits in the vulcanization of rubber as investigated in this research. Curing, mechanical, and thermal characteristics were investigated to find out the suitability of MgO in the vulcanization of rubber. Curing studies reveal that significant reductions in the optimum curing times are found by using MgO as a co-cure activator. Especially, the rate of vulcanization with conventional 5 phr (per hundred grams) ZnO can be enhanced by more than double, going from 0.3 Nm/min to 0.85 Nm/min by the use of a 3:2 ratio of MgO to ZnO cure activator system that should have high industrial importance. Mechanical and thermal properties investigations suggest that MgO as a co-cure activator used at 60% can provide 7.5% higher M100 (modulus at 100% strain) (0.58 MPa from 0.54 MPa), 20% higher tensile strength (23.7 MPa from 19.5 MPa), 15% higher elongation at break (1455% from 1270%), 68% higher fracture toughness (126 MJ/m3 from 75 MJ/m3), and comparable thermal stability than conventionally using 100 % ZnO. Especially, MgO as a co-cure activator could be very useful for improving the fracture toughness in rubber compounds compared to ZnO as a single-site curing activator. The significant improvements in the curing and mechanical properties suggest that MgO and ZnO undergo chemical interactions during vulcanization. Such rubber compounds can be useful in advanced tough and stretchable applications.
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Pradhan S, Goswami D, Ratna D, Chattopadhyay S. Graphene nanoplatelet filled elastomer composites; influence of different matrices on the dispersion, electrical and mechanical properties. POLYM ENG SCI 2022. [DOI: 10.1002/pen.26154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Sudip Pradhan
- Rubber Technology Cell Naval Dockyard Mumbai India
- Rubber Technology Centre Indian Institute of Technology Kharagpur Kharagpur India
| | - Debottam Goswami
- School of Nano‐science and Technology Indian Institute of Technology Kharagpur Kharagpur India
| | | | - Santanu Chattopadhyay
- Rubber Technology Centre Indian Institute of Technology Kharagpur Kharagpur India
- School of Nano‐science and Technology Indian Institute of Technology Kharagpur Kharagpur India
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Nagendra B, Leuteritz A, Bhoje Gowd E. Multiwalled Carbon Nanotubes Decorated with Layered Double Hydroxides as Multifunctional Fillers for Polypropylene. ChemistrySelect 2022. [DOI: 10.1002/slct.202201922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Baku Nagendra
- Materials Science and Technology Division CSIR-National Institute for Interdisciplinary Science and Technology, Trivandrum 695 019 Kerala India 2515474
- Academy of Scientific and Innovative Research (AcSIR) Ghaziabad 201 002 India
| | - Andreas Leuteritz
- Leibniz-Institut für Polymerforschung Dresden e.V. D-01069 Dresden Germany
| | - E. Bhoje Gowd
- Materials Science and Technology Division CSIR-National Institute for Interdisciplinary Science and Technology, Trivandrum 695 019 Kerala India 2515474
- Academy of Scientific and Innovative Research (AcSIR) Ghaziabad 201 002 India
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10
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Sun M, Wang Y, Wang X, Liu Q, Li M, Shulga YM, Li Z. In-Situ Synthesis of Layered Double Hydroxide/Silica Aerogel Composite and Its Thermal Safety Characteristics. Gels 2022; 8:gels8090581. [PMID: 36135293 PMCID: PMC9498337 DOI: 10.3390/gels8090581] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 09/05/2022] [Accepted: 09/08/2022] [Indexed: 11/16/2022] Open
Abstract
To adjust the thermal safety of hydrophobic silica aerogel, layered double hydroxide (LDH)/silica aerogel (SA) composites were prepared by an in-situ sol-gel process at ambient pressure. This study found the physical combination of SA and MgAl-LDH based on the FTIR spectra and phase composition of LDH/SA. The N2 sorption analysis confirms that the introduction of MgAl-LDH does not change the mesoporous attribution of LDH/SA significantly. With the increase in MgAl-LDH addictive content, the low density (0.12–0.13 g/cm3), low thermal conductivity (24.28–26.38 mW/m/K), and large specific surface area (730.7–903.7 m2g) of LDH/SA are still maintained, which can satisfy the requirements of thermal insulation. The TG-DSC analysis demonstrates that the endothermic effects and metal oxides formed during the MgAl-LDH decomposition are beneficial to the improvement of the thermal stability of LDH/SA composites. In addition, it was found that the gross calorific values of LDH/SA composites decrease with an increase in MgAl-LDH addictive content, all of which are lower than that of the pure SA. The research outcomes indicate that the thermal safety of LDH/SA composites is enhanced significantly by doping MgAl-LDH without impairing too many of the excellent properties, which benefits their expansion in the thermal insulation field.
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Affiliation(s)
- Mengtian Sun
- School of Resources and Safety Engineering, Central South University, Changsha 410083, China
| | - Yang Wang
- School of Resources and Safety Engineering, Central South University, Changsha 410083, China
| | - Xiaowu Wang
- School of Resources and Safety Engineering, Central South University, Changsha 410083, China
| | - Qiong Liu
- School of Resources and Safety Engineering, Central South University, Changsha 410083, China
| | - Ming Li
- School of Resources and Safety Engineering, Central South University, Changsha 410083, China
| | - Yury M. Shulga
- Institute of Problems of Chemical Physics, Russian Academy of Sciences, Chernogolovka 142432, Russia
- National University of Science and Technology MISIS, Leninsky pr. 4, Moscow 119049, Russia
| | - Zhi Li
- School of Resources and Safety Engineering, Central South University, Changsha 410083, China
- Correspondence:
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Huang C, Tang C, Wu Q, Zhu Q. Magnetic MnFe 2O 4/ZnFe-LDH for Enhanced Phosphate and Cr (VI) Removal from Water. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:59224-59234. [PMID: 35381917 DOI: 10.1007/s11356-022-20049-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Accepted: 03/29/2022] [Indexed: 06/14/2023]
Abstract
Due to the layered structure and recycling characteristics, magnetic MnFe2O4/ZnFe-LDH was prepared by co-precipitation. In this study, we intensively explored MnFe2O4/ZnFe-LDH for water purification compared with the ZnFe-LDH. The morphological and structural characteristics of the obtained products were systematically characterized. MnFe2O4/ZnFe-LDH exhibits the maximum adsorption capacity of 94.52 mg/g for phosphate and 49.03 mg/g for Cr (VI), respectively, which is superior to that of the ZnFe-LDH, indicating that the magnetic MnFe2O4 effectively enhanced adsorption performance. Meanwhile, the mechanism of adsorption of phosphate and Cr (VI) was briefly studied, where the metal center ion in MnFe2O4/ZnFe-LDH and between layers of SO42- serves as capture sites for phosphate and Cr (VI) removal. Furthermore, the MnFe2O4/ZnFe-LDH can be used for magnetic recycled and still maintained excellent removal efficiency (70%) for phosphate and Cr (VI) after five adsorption-desorption cycles. This work could open a new vista of designing magnetic novel adsorbents in environmental remediation.
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Affiliation(s)
- Congxin Huang
- School of Civil Engineering and Architecture, East China Jiao Tong University, Jiangxi, 330013, China
| | - Chaochun Tang
- School of Civil Engineering and Architecture, East China Jiao Tong University, Jiangxi, 330013, China.
| | - Qingqing Wu
- School of Civil Engineering and Architecture, East China Jiao Tong University, Jiangxi, 330013, China
| | - Qing Zhu
- Continuing Education College, Tongji University, Shanghai, 200092, China
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12
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Gomez NAG, Machado Silva G, Wypych F. Intercalation of anionic organic ultraviolet absorbers in bimetallic and trimetallic layered double hydroxides for low-density polyethylene protection. Polym Bull (Berl) 2022. [DOI: 10.1007/s00289-021-03640-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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13
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Viscusi G, D'Amico F, Gorrasi G. In situ one‐step fabrication of layered double hydroxide deposited on cellulose: Effect of modified cellulose on physical properties of polyurethane composites. POLYM ADVAN TECHNOL 2022. [DOI: 10.1002/pat.5684] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Gianluca Viscusi
- Department of Industrial Engineering University of Salerno Fisciano Italy
| | - Francesca D'Amico
- Department of Industrial Engineering University of Salerno Fisciano Italy
| | - Giuliana Gorrasi
- Department of Industrial Engineering University of Salerno Fisciano Italy
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14
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Ma L, Liu X, Sheng Y, Guo Y. Flame retardancy of silicone rubber foam containing modified hydrotalcite. J Appl Polym Sci 2022. [DOI: 10.1002/app.52255] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Li Ma
- College of Safety Science and Engineering Xi'an University of Science and Technology Xi'an China
| | - Xixi Liu
- College of Safety Science and Engineering Xi'an University of Science and Technology Xi'an China
| | - Youjie Sheng
- College of Safety Science and Engineering Xi'an University of Science and Technology Xi'an China
| | - Ying Guo
- College of Mining Engineering China University of Mining and Technology Xuzhou China
- Yanzhou Coal Mining Co., Ltd Zoucheng Shandong China
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15
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Mukherjee M, Mandal S, Gnanasundaram S, Das BN. Polyurethane‐layered double hydroxide nanocomposite foam: in‐situ synthesis by reaction injection molding and characterization. POLYM INT 2022. [DOI: 10.1002/pi.6365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Moumita Mukherjee
- Shoe & Product Design Centre (SPDC), CSIR – Central Leather Research Institute Chennai 600020 India
| | - Sujata Mandal
- Centre for Analysis, Testing, Evaluation& Reporting Services (CATERS), CSIR – Central Leather Research Institute Chennai 600020 India
| | - Saraswathy Gnanasundaram
- Shoe & Product Design Centre (SPDC), CSIR – Central Leather Research Institute Chennai 600020 India
| | - Bhabendra Nath Das
- Shoe & Product Design Centre (SPDC), CSIR – Central Leather Research Institute Chennai 600020 India
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16
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Korany MA, Mahmoud RK. A new approach for determination of water soluble hexavalent chromium in real cement and industrial water samples using Ni-Fe layered double hydroxides/urea/glycerol nanocomposite based potentiometric sensor. Microchem J 2021. [DOI: 10.1016/j.microc.2021.106890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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17
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Nanodiamond—Carbon Black Hybrid Filler System for Demanding Applications of Natural Rubber—Butadiene Rubber Composite. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app112110085] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The objective of the study was to investigate the effect of the partial replacement of carbon black (CB) by nanodiamonds (NDs) on the vulcanization, mechanical and dynamic properties of a natural rubber—butadiene rubber compound, a typical elastomer compound found in several applications (the tire and mining industry, for example). A studied hybrid filler system resulted in a 28% increase in tensile strength and 29% increase in 300% modulus at low ND loadings even though the total weight fraction of the filler system was kept constant at 25 parts per hundred rubber. The hybrid filler system improved dispersion of both fillers as was proven by scanning electron microscopy and the Payne effect study. In addition, the replacement of 2.5 and 5 phr CB by NDs resulted in 62% improvement in wear resistance. The DMA study showed that a certain ND-CB filler combination has a positive effect on tire properties such as wet grip and rolling resistance.
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18
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Active Corrosion Protection of Mg–Al Layered Double Hydroxide for Magnesium Alloys: A Short Review. COATINGS 2021. [DOI: 10.3390/coatings11111316] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Layered double hydroxides (LDHs) have been successfully applied in surface protection and functionalization of metal materials owing to their special structure, composition, controllability, anion exchange, and other excellent properties. Herein, this review focused on the most common LDH preparation methods on magnesium alloys in the past 10 years by summarizing about 70 research papers. At the same time, based on the corrosion protection mechanism of LDH materials, the performance of LDH films and LDH as filler on metal substrates was briefly introduced. The surface of LDH materials were chemically modified to enhance their compatibility with solvents, and their corrosion resistance function was developed as an additive. Finally, LDH-based composite coatings on Mg alloys by surface pretreatment and chemical modification were discussed.
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19
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van Tonder L, Labuschagné FJWJ. Systematic Literature Review of the Effect of Layered Double Hydroxides on the Mechanical Properties of Rubber. Polymers (Basel) 2021; 13:polym13213716. [PMID: 34771273 PMCID: PMC8587788 DOI: 10.3390/polym13213716] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 10/14/2021] [Accepted: 10/18/2021] [Indexed: 11/29/2022] Open
Abstract
Layered double hydroxides (LDHs) have attracted interest as reinforcing fillers in elastomers due to their ease of synthesis and customisability. A systematic review was performed on the effect of LDHs on the mechanical properties of elastomers using the Scopus database. Of the 61 articles relevant to the search criteria, the majority were published on polyurethane (PU) and nitrile butadiene rubber (NBR). Mg-Al LDH was used in most of the studies and Zn-Al LDH was used second most common. LDH can act as a reinforcing filler, typically increasing tensile strength even at low concentrations, so it could be used as an alternative to traditional reinforcing fillers for elastomers. LDH can also be made a functional filler by selecting the right metals and interlayer anions. It was found that Mg-Al LDH and Zn-Al LDH can both participate in crosslinking reactions and can replace MgO and ZnO, respectively. Less Zn ions are required for crosslinking when LDH is used than when ZnO is used, making LDH more environmentally friendly. Organic modification is usually required to improve compatibility with the elastomer matrix, especially in non-polar elastomers. It enables exfoliation of the LDH and intercalation of polymer chains into the LDH interlayer to occur. Organic modifiers can also be used to functionalise the LDH. Stearic acid used in crosslinking systems can be replaced by stearate anions from stearate-modified LDH.
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20
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Dharmasaroja N, Ratana T, Tungkamani S, Sornchamni T, Simakov DSA, Phongaksorn M.
CO
2
reforming of methane over the growth of hierarchical
Ni
nanosheets/
Al
2
O
3
‐MgO
synthesized via the ammonia vapour diffusion impregnation. CAN J CHEM ENG 2021. [DOI: 10.1002/cjce.23992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Nichthima Dharmasaroja
- Department of Industrial Chemistry King Mongkut's University of Technology North Bangkok Bangkok Thailand
- Research and Development Center for Chemical Engineering Unit Operation and Catalyst Design (RCC) King Mongkut's University of Technology North Bangkok Bangkok Thailand
| | - Tanakorn Ratana
- Department of Industrial Chemistry King Mongkut's University of Technology North Bangkok Bangkok Thailand
- Research and Development Center for Chemical Engineering Unit Operation and Catalyst Design (RCC) King Mongkut's University of Technology North Bangkok Bangkok Thailand
| | - Sabaithip Tungkamani
- Department of Industrial Chemistry King Mongkut's University of Technology North Bangkok Bangkok Thailand
- Research and Development Center for Chemical Engineering Unit Operation and Catalyst Design (RCC) King Mongkut's University of Technology North Bangkok Bangkok Thailand
| | - Thana Sornchamni
- Analytical & Petrochemical Department PTT Research and Technology Institute Wangnoi Thailand
| | - David S. A. Simakov
- Department of Chemical Engineering University of Waterloo Waterloo Ontario Canada
| | - Monrudee Phongaksorn
- Department of Industrial Chemistry King Mongkut's University of Technology North Bangkok Bangkok Thailand
- Research and Development Center for Chemical Engineering Unit Operation and Catalyst Design (RCC) King Mongkut's University of Technology North Bangkok Bangkok Thailand
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21
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The outstanding interfacial adhesion between acrylo-POSS/natural rubber composites and polyamide-based cords: ‘An environmentally friendly alternative to resorcinol-formaldehyde latex coating’. POLYMER 2021. [DOI: 10.1016/j.polymer.2021.123880] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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22
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Noorani Khomeyrani SF, Ahmadi Azqhandi MH, Ghalami-Choobar B. Rapid and efficient ultrasonic assisted adsorption of PNP onto LDH-GO-CNTs: ANFIS, GRNN and RSM modeling, optimization, isotherm, kinetic, and thermodynamic study. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.115917] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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23
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Curing kinetics and ionic interactions in layered double hydroxides–nitrile rubber Mg–Al-LDHs–XNBR composites. Polym Bull (Berl) 2021. [DOI: 10.1007/s00289-020-03249-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
AbstractThe carboxylated butadiene–acrylonitrile XNBR composites containing layered double hydroxides (Mg–Al-LDHs) were prepared with the aim to investigate the effect of various Mg:Al ratio in the filler composition on the rheological behavior, kinetic of curing and viscoelastic properties of final material. Due to the presence of metal cations, LDHs can form ionic cross-links with carboxylic functional groups of XNBR nitrile rubber. The DSC analysis indicated lower ranges of curing temperatures as the Mg:Al ratio raised (90–184 °C for Pural MG63, 88–187 °C for Pural MG70). The apparent energy of activation Ea decreased with increasing Mg:Al ratio reaching the value of 111.46 kJˑmole−1 for XNBR composite containing Pural MG70. The rheological analysis revealed the presence of specific polymer–nanofillers and fillers–fillers interactions. The XNBR–LDHs rubbers exhibited two transitions corresponding to the glass temperature of elastomer Tg (in range of −13.08 to −13.60 °C) and the ionic transition temperature Tα′ (in range of 32.95–37.90 °C). The ionic transition temperature Tα′ was not observed for the nitrile rubber composite containing Pural MG5 with the lowest Mg:Al ratio. The formed ordered ionic phase significantly affected the viscoelastic behavior of XNBR composites at room and sub-zero temperatures leading to the increase in the storage modulus G′. Therefore, among the various possible applications of LDHs, their use in rubber technology offers the potential for production of environmentally friendly rubber products cured without any additional curatives.
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24
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Ji J, Huang W, Wang L, Chen L, Wei Y, Liu R, Cheng J, Wu H. Synthetic Iowaite Can Effectively Remove Inorganic Arsenic from Marine Extract. Molecules 2021; 26:molecules26103052. [PMID: 34065389 PMCID: PMC8160602 DOI: 10.3390/molecules26103052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 05/14/2021] [Accepted: 05/14/2021] [Indexed: 11/16/2022] Open
Abstract
For the removal of arsenic from marine products, iowaite was prepared and investigated to determine the optimal adsorption process of arsenic. Different chemical forms of arsenic (As(III), As(V)) with varying concentrations (0.15, 1.5, 5, 10, 15, and 20 mg/L) under various conditions including pH (3, 5, 7, 9, 11) and contact time (1, 2, 5, 10, 15, 30, 60, 120, 180 min) were exposed to iowaite. Adsorption isotherms and metal ions kinetic modeling onto the adsorbent were determined based on Langmuir, Freundlich, first- and second-order kinetic models. The adsorption onto iowaite varied depending on the conditions. The adsorption rates of standard solution, As(III) and As(V) exceeded 95% under proper conditions, while high complexity was noted with marine samples. As(III) and As(V) from Mactra veneriformis extraction all decreased when exposed to iowaite. The inclusion morphology and interconversion of organic arsenic limit adsorption. Iowaite can be efficiently used for inorganic arsenic removal from wastewater and different marine food products, which maybe other adsorbent or further performance of iowaite needs to be investigated for organic arsenic.
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Affiliation(s)
- Jing Ji
- College of Pharmacology, Nanjing University of Chinese Medicine, Nanjing 210023, China; (J.J.); (L.W.); (L.C.); (Y.W.); (R.L.)
- Jiangsu Key Laboratory of Research and Development in Marnie Bio-resource Pharmaceutics, Nanjing 201123, China
- Jiangsu Collaborative Innovation Center of Chinese Medicinal Resources Industrialization, Nanjing 210023, China
| | - Wenwen Huang
- Third Institute of Oceanography, Ministry of Natural Resources, Xiamen 361005, China;
| | - Lingchong Wang
- College of Pharmacology, Nanjing University of Chinese Medicine, Nanjing 210023, China; (J.J.); (L.W.); (L.C.); (Y.W.); (R.L.)
| | - Lu Chen
- College of Pharmacology, Nanjing University of Chinese Medicine, Nanjing 210023, China; (J.J.); (L.W.); (L.C.); (Y.W.); (R.L.)
| | - Yuanqing Wei
- College of Pharmacology, Nanjing University of Chinese Medicine, Nanjing 210023, China; (J.J.); (L.W.); (L.C.); (Y.W.); (R.L.)
- Jiangsu Key Laboratory of Research and Development in Marnie Bio-resource Pharmaceutics, Nanjing 201123, China
- Jiangsu Collaborative Innovation Center of Chinese Medicinal Resources Industrialization, Nanjing 210023, China
| | - Rui Liu
- College of Pharmacology, Nanjing University of Chinese Medicine, Nanjing 210023, China; (J.J.); (L.W.); (L.C.); (Y.W.); (R.L.)
- Jiangsu Key Laboratory of Research and Development in Marnie Bio-resource Pharmaceutics, Nanjing 201123, China
- Jiangsu Collaborative Innovation Center of Chinese Medicinal Resources Industrialization, Nanjing 210023, China
| | - Jianming Cheng
- College of Pharmacology, Nanjing University of Chinese Medicine, Nanjing 210023, China; (J.J.); (L.W.); (L.C.); (Y.W.); (R.L.)
- Jiangsu Key Laboratory of Research and Development in Marnie Bio-resource Pharmaceutics, Nanjing 201123, China
- Jiangsu Collaborative Innovation Center of Chinese Medicinal Resources Industrialization, Nanjing 210023, China
- Correspondence: (J.C.); (H.W.)
| | - Hao Wu
- College of Pharmacology, Nanjing University of Chinese Medicine, Nanjing 210023, China; (J.J.); (L.W.); (L.C.); (Y.W.); (R.L.)
- Jiangsu Key Laboratory of Research and Development in Marnie Bio-resource Pharmaceutics, Nanjing 201123, China
- Jiangsu Collaborative Innovation Center of Chinese Medicinal Resources Industrialization, Nanjing 210023, China
- Correspondence: (J.C.); (H.W.)
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25
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Maciejewska M, Sowińska A. Influence of Fillers and Ionic Liquids on the Crosslinking and Performance of Natural Rubber Biocomposites. Polymers (Basel) 2021; 13:polym13101656. [PMID: 34069680 PMCID: PMC8160702 DOI: 10.3390/polym13101656] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 05/14/2021] [Accepted: 05/17/2021] [Indexed: 12/15/2022] Open
Abstract
This work concerns the effect of fillers and ionic liquids on the cure characteristics of natural rubber (NR) compounds, as well as the mechanical and thermal properties of the vulcanizates. Three types of white filler were applied, such as cellulose, nanosized silica and hydrotalcite, to modify the performance of NR composites. Additionally, ionic liquids (ILs) with bromide anion and different cations, i.e., 1-butyl-3-methylimidazolium (Bmi) and 1-butyl-3-methylpyrrolidinium (Bmpyr), were used to improve the cure characteristics of NR compounds and functional properties of the vulcanizates. The type of filler and the structure of ILs were proved to affect the rheometric properties and cure characteristics of NR compounds as well as the performance of the NR vulcanizates. Owing to the adsorption of curatives onto the surface, silica reduced the activity of the crosslinking system, prolonging the optimal vulcanization time of NR compounds and reducing the crosslinking degree of the elastomer. However, silica-filled NR exhibited the highest thermal stability. Hydrotalcite increased the crosslink density and, consequently, the mechanical properties of the vulcanizates, but deteriorated their thermal stability. ILs beneficially influenced the cure characteristics of NR compounds, as well as the crosslink density and mechanical performance of the vulcanizates, particularly those filled with silica. Cellulose did not significantly affect the vulcanization of NR compounds and crosslink density of the vulcanizates compared to the unfilled elastomer, but deteriorated their tensile strength. On the other hand, cellulose improved the thermal stability and did not considerably alter the damping properties of the vulcanizates.
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26
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Makvandi P, Josic U, Delfi M, Pinelli F, Jahed V, Kaya E, Ashrafizadeh M, Zarepour A, Rossi F, Zarrabi A, Agarwal T, Zare EN, Ghomi M, Kumar Maiti T, Breschi L, Tay FR. Drug Delivery (Nano)Platforms for Oral and Dental Applications: Tissue Regeneration, Infection Control, and Cancer Management. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:2004014. [PMID: 33898183 PMCID: PMC8061367 DOI: 10.1002/advs.202004014] [Citation(s) in RCA: 65] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 12/12/2020] [Indexed: 05/09/2023]
Abstract
The oral cavity and oropharynx are complex environments that are susceptible to physical, chemical, and microbiological insults. They are also common sites for pathological and cancerous changes. The effectiveness of conventional locally-administered medications against diseases affecting these oral milieus may be compromised by constant salivary flow. For systemically-administered medications, drug resistance and adverse side-effects are issues that need to be resolved. New strategies for drug delivery have been investigated over the last decade to overcome these obstacles. Synthesis of nanoparticle-containing agents that promote healing represents a quantum leap in ensuring safe, efficient drug delivery to the affected tissues. Micro/nanoencapsulants with unique structures and properties function as more favorable drug-release platforms than conventional treatment approaches. The present review provides an overview of newly-developed nanocarriers and discusses their potential applications and limitations in various fields of dentistry and oral medicine.
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Affiliation(s)
- Pooyan Makvandi
- Chemistry Department, Faculty of ScienceShahid Chamran University of AhvazAhvaz6153753843Iran
| | - Uros Josic
- Department of Biomedical and Neuromotor SciencesUniversity of BolognaVia San Vitale 59Bologna40125Italy
| | - Masoud Delfi
- Department of Chemical SciencesUniversity of Naples “Federico II”Complesso Universitario Monte S. Angelo, Via CintiaNaples80126Italy
| | - Filippo Pinelli
- Department of Chemistry, Materials and Chemical EngineeringPolitecnico di Milano Technical UniversityMilano20133Italy
| | - Vahid Jahed
- Biomedical Engineering Division, Faculty of Chemical EngineeringTarbiat Modares UniversityTehranIran
| | - Emine Kaya
- Faculty of DentistryIstanbul Okan UniversityTuzla CampusTuzlaIstanbul34959Turkey
| | - Milad Ashrafizadeh
- Faculty of Engineering and Natural SciencesSabanci UniversityOrta Mahalle, Üniversite Caddesi No. 27, OrhanlıTuzlaIstanbul34956Turkey
- Sabanci University Nanotechnology Research and Application Center (SUNUM)TuzlaIstanbul34956Turkey
| | - Atefeh Zarepour
- Sabanci University Nanotechnology Research and Application Center (SUNUM)TuzlaIstanbul34956Turkey
| | - Filippo Rossi
- Department of Chemistry, Materials and Chemical EngineeringPolitecnico di Milano Technical UniversityMilano20133Italy
| | - Ali Zarrabi
- Sabanci University Nanotechnology Research and Application Center (SUNUM)TuzlaIstanbul34956Turkey
| | - Tarun Agarwal
- Department of BiotechnologyIndian Institute of Technology KharagpurKharagpurWest Bengal721302India
| | | | - Matineh Ghomi
- Chemistry Department, Faculty of ScienceShahid Chamran University of AhvazAhvaz6153753843Iran
| | - Tapas Kumar Maiti
- Department of BiotechnologyIndian Institute of Technology KharagpurKharagpurWest Bengal721302India
| | - Lorenzo Breschi
- Department of Biomedical and Neuromotor SciencesUniversity of BolognaVia San Vitale 59Bologna40125Italy
| | - Franklin R Tay
- The Dental College of GeorgiaAugusta University1430 John Wesley Gilbert DriveAugustaGA30192USA
- The Graduate SchoolAugusta UniversityAugustaGA30912USA
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Wu K, Xu S, Tian XY, Zeng HY, Hu J, Guo YH, Jian J. Renewable lignin-based surfactant modified layered double hydroxide and its application in polypropylene as flame retardant and smoke suppression. Int J Biol Macromol 2021; 178:580-590. [PMID: 33631261 DOI: 10.1016/j.ijbiomac.2021.02.148] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 02/15/2021] [Accepted: 02/19/2021] [Indexed: 11/17/2022]
Abstract
A novel and environmentally friendly lignin-based surfactant sodium lignosulfonate (SLS) modified layered double hydroxide (LDH) flame retardant (LDH-LS) was fabricated via co-precipitation method, and subsequently incorporated into polypropylene (PP) matrix to obtain the PP and LDH-LS composites (PP/LDH-LS) by melt blending method. The XRD, FT-IR and XPS results indicated that SLS had successfully modified LDH by adsorbing on the surface of the LDH nanosheet. The WCA and SEM results revealed that the hydrophobic property of LDH-LS had been evidently improved, and it displayed a more homogeneous dispersion than virgin LDH in the PP matrix. Furthermore, cone calorimetry tests (CCT) illustrated that the peak heat release rate (PHRR), total heat release (THR), and total smoke release (TSR) of PP/LDH-LS composites exhibited declines of 62.9%, 25.1%, and 43.3% compared with those of Neat PP, respectively. Besides, the PP/LDH-LS achieved a LOI value of 29.4% and a UL-94 V-0 rating, whereas the PP/LDH showed only a LOI value of 25.2% and a UL-94 V-2 rating at 20 wt% loading. These improvements of flame retardant properties can be attributed to that the well-dispersed LDH-LS and synergistic flame retardancy between LDH and SLS.
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Affiliation(s)
- Kun Wu
- School of Chemical Engineering, Xiangtan University, Xiangtan 411105, Hunan, China
| | - Sheng Xu
- School of Chemical Engineering, Xiangtan University, Xiangtan 411105, Hunan, China.
| | - Xian-Yao Tian
- School of Chemical Engineering, Xiangtan University, Xiangtan 411105, Hunan, China
| | - Hong-Yan Zeng
- School of Chemical Engineering, Xiangtan University, Xiangtan 411105, Hunan, China.
| | - Jie Hu
- School of Chemical Engineering, Xiangtan University, Xiangtan 411105, Hunan, China
| | - Yi-Hui Guo
- School of Chemical Engineering, Xiangtan University, Xiangtan 411105, Hunan, China
| | - Jian Jian
- School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan 411201, China
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Kaseem M, Ramachandraiah K, Hossain S, Dikici B. A Review on LDH-Smart Functionalization of Anodic Films of Mg Alloys. NANOMATERIALS (BASEL, SWITZERLAND) 2021; 11:536. [PMID: 33669848 PMCID: PMC7923239 DOI: 10.3390/nano11020536] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Revised: 02/11/2021] [Accepted: 02/17/2021] [Indexed: 12/05/2022]
Abstract
This review presents an overview of the recent developments in the synthesis of layered double hydroxide (LDH) on the anodized films of Mg alloys prepared by either conventional anodizing or plasma electrolytic oxidation (PEO) and the applications of the formed composite ceramics as smart chloride traps in corrosive environments. In this work, the main fabrication approaches including co-precipitation, in situ hydrothermal, and an anion exchange reaction are outlined. The unique structure of LDH nanocontainers enables them to intercalate several corrosion inhibitors and release them when required under the action of corrosion-relevant triggers. The influences of different variables, such as type of cations, the concentration of salts, pH, and temperature, immersion time during the formation of LDH/anodic film composites, on the electrochemical response are also highlighted. The correlation between the dissolution rate of PEO coating and the growth rate of the LDH film was discussed. The challenges and future development strategies of LDH/anodic films are also highlighted in terms of industrial applications of these materials.
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Affiliation(s)
- Mosab Kaseem
- Department of Nanotechnology and Advanced Materials Engineering, Sejong University, Seoul 05006, Korea
| | - Karna Ramachandraiah
- Department of Food Science and Biotechnology, College of Life Science, Sejong University, Seoul 05006, Korea;
| | - Shakhawat Hossain
- Department of Industrial and Production Engineering, Jashore University of Science and Technology, Jashore 7408, Bangladesh;
| | - Burak Dikici
- Department of Metallurgical and Materials Engineering, Ataturk University, Erzurum 25240, Turkey;
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29
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Khataei MM, Yamini Y, Shamsayei M. Applications of porous frameworks in solid-phase microextraction. J Sep Sci 2021; 44:1231-1263. [PMID: 33433916 DOI: 10.1002/jssc.202001172] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Revised: 12/27/2020] [Accepted: 12/30/2020] [Indexed: 01/26/2023]
Abstract
Porous frameworks are a term of attracting solid materials assembled by interconnection of molecules and ions. These trendy materials due to high chemical and thermal stability, well-defined pore size and structure, and high effective surface area gained attention to employ as extraction phase in sample pretreatment methods before analytical analysis. Solid-phase microextraction is an important subclass of sample preparation technique that up to now different configurations of this method have been introduced to get adaptable with different environments and analytical instruments. In this review, theoretical aspect and different modes of solid-phase microextraction method are investigated. Different classes of porous frameworks and their applications as extraction phase in the proposed microextraction method are evaluated. Types and features of supporting substrates and coating procedures of porous frameworks on them are reviewed. At the end, the prospective and the challenges ahead in this field are discussed.
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Affiliation(s)
- Mohammad Mahdi Khataei
- Department of Chemistry, Tarbiat Modares University, Tehran, Iran.,Department of Chemistry, Centre for Analysis and Synthesis, Lund University, Lund, Sweden
| | - Yadollah Yamini
- Department of Chemistry, Tarbiat Modares University, Tehran, Iran
| | - Maryam Shamsayei
- Department of Chemistry, Tarbiat Modares University, Tehran, Iran
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Biodegradation of Poly (Butylene Succinate) (PBS)/Stearate Modified Magnesium-Aluminium Layered Double Hydroxide Composites under Marine Conditions Prepared via Melt Compounding. Molecules 2020; 25:molecules25235766. [PMID: 33297487 PMCID: PMC7730599 DOI: 10.3390/molecules25235766] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2020] [Revised: 11/30/2020] [Accepted: 12/04/2020] [Indexed: 11/17/2022] Open
Abstract
In the present work, polybutylene succinate (PBS)/stearate modified magnesium-aluminium layered double hydroxide (St-Mg-Al LDH) composites were prepared via melt processing and the effect of different loadings of St-Mg-Al LDH on the degradation behaviour of PBS under marine conditions was investigated. The morphological, mechanical and thermal characteristics of the composites were studied using different characterisation techniques. Optical imaging and scanning electron microscopy revealed that the incorporation of St-Mg-Al LDH accelerates the degradation of PBS along with the activity of microorganisms adhered to the composite films. PBS/St-Mg-Al LDH composites are found to have lower thermal degradation temperatures than those of pure PBS. The decrease in thermal stability is correlated with the degradation of PBS due to the catalytic action Mg and Al present in LDH. Tensile and DMA analysis revealed that the addition of St-Mg-Al LDH did not have a significant impact on the mechanical properties of PBS.
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Vasile E, Radu IC, Galateanu B, Rapa M, Hudita A, Jianu D, Stanescu PO, Cioflan H, Zaharia C. Novel Nanocomposites Based on Bacterial Polyester/LDH-SDS Clay for Stem Cells Delivery in Modern Wound Healing Management. MATERIALS 2020; 13:ma13204488. [PMID: 33050441 PMCID: PMC7601887 DOI: 10.3390/ma13204488] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 09/24/2020] [Accepted: 10/04/2020] [Indexed: 12/14/2022]
Abstract
Nanocomposite materials based on poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBHV) and modified mineral clay layered double hydroxides (LDH-SDS) were explored as novel nanostructured materials for potential tissue engineering applications. The mineral clay inorganic phase was modified with an anionic long-chain structure of carbon atoms, such as sodium dodecyl sulfate, in order to increase the compatibility between the two phases. The melt intercalation method used for nanocomposite fabrication ensures a good dispersion of the modified LDH-SDS within the polymer matrix without using a toxic solvent (chloroform). The nanocomposites were found to have an intercalated/exfoliated structure with an enhanced Young modulus and increased stiffness. This could allow them to be considered for autologous stem cells dressings in the view of efficient wound healing applications.
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Affiliation(s)
- Eugeniu Vasile
- Faculty of Applied Chemistry and Materials Science, Politehnica University of Bucharest, 060042 Bucharest, Romania;
| | - Ionut-Cristian Radu
- Advanced Polymer Materials Group, Politehnica University of Bucharest, 060042 Bucharest, Romania; (I.-C.R.); (P.-O.S.)
| | - Bianca Galateanu
- Department of Biochemistry and Molecular Biology, University of Bucharest, 91-95 Splaiul Independentei Street, 050095 Bucharest, Romania; (B.G.); (A.H.)
| | - Maria Rapa
- ECOMET Center, Politehnica University of Bucharest, 313 Splaiul Independentei, 060042 Bucharest, Romania;
| | - Ariana Hudita
- Department of Biochemistry and Molecular Biology, University of Bucharest, 91-95 Splaiul Independentei Street, 050095 Bucharest, Romania; (B.G.); (A.H.)
| | - Dana Jianu
- International Society of Regenerative Medicine and Surgery, 38-40 T. Stefan Street, 011658 Bucharest, Romania;
| | - Paul-Octavian Stanescu
- Advanced Polymer Materials Group, Politehnica University of Bucharest, 060042 Bucharest, Romania; (I.-C.R.); (P.-O.S.)
| | - Horia Cioflan
- SANADOR Clinic Hospital, Sevastopol Street, No. 9, Sector 1, 010991 Bucharest, Romania;
- Department of General Surgery, Oncology Institute “Prof.dr. Alexandru Trestioreanu”, Sos. Fundeni, Bucharest, No. 252, Sector 2, 022328 Bucharest, Romania
| | - Catalin Zaharia
- Advanced Polymer Materials Group, Politehnica University of Bucharest, 060042 Bucharest, Romania; (I.-C.R.); (P.-O.S.)
- Correspondence: ; Tel.: +40-727-694-492
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Leão AD, da Silva LA, de Oliveira Silva Ribeiro F, da Silva DA, de França EJ, Aquino KADS, Soares-Sobrinho JL. Influence of Nonmodified Layered Double Hydroxide (LDH) Metal Constituents in PMMA/LDH Nanocomposites. J Inorg Organomet Polym Mater 2020. [DOI: 10.1007/s10904-020-01742-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Hoxha A, Gillam DG, Agha A, Karpukhina N, Bushby AJ, Patel MP. Novel fluoride rechargeable dental composites containing MgAl and CaAl layered double hydroxide (LDH). Dent Mater 2020; 36:973-986. [PMID: 32536588 DOI: 10.1016/j.dental.2020.04.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 04/26/2020] [Indexed: 11/29/2022]
Abstract
OBJECTIVE This study aims to incorporate 2:1 MgAl and 2:1 CaAl layered double hydroxides (LDHs) in experimental dental-composites to render them fluoride rechargeable. The effect of LDH on fluoride absorption and release, and their physico-mechanical properties are investigated. METHODS 2:1 CaAl and 2:1 MgAl LDH-composite discs prepared with 0, 10 and 30wt% LDH were charged with fluoride (48h) and transferred to deionized water (DW)/artificial saliva (AS). Fluoride release/re-release was measured every 24h (ion-selective electrodes) with DW/AS replaced daily, and samples re-charged (5min) with fluoride every 2 days. Five absorption-release cycles were conducted over 10 days. CaAl and MgAl LDH rod-shaped specimens (dry and hydrated; 0, 10 and 30wt%) were studied for flexural strength and modulus. CaAl and MgAl LDH-composite discs (0, 10, 30 and 45wt% LDH) were prepared to study water uptake (over 7 weeks), water desorption (3 weeks), diffusion coefficients, solubility and cation release (ICP-OES). RESULTS CaAl LDH and MgAl LDH-composites significantly increased the amount of fluoride released in both media (P<0.05). In AS, the mean release after every recharge was greater for MgAl LDH-composites compared to CaAl LDH-composites (P<0.05). After every recharge, the fluoride release was greater than the previous release cycle (P<0.05) for all LDH-composites. Physico-mechanical properties of the LDH-composites demonstrated similar values to those reported in literature. The solubility and cation release showed a linear increase with LDH loading. SIGNIFICANCE LDH-composites repeatedly absorbed/released fluoride and maintained desired physico-mechanical properties. A sustained low-level fluoride release with LDH-composites could lead to a potential breakthrough in preventing early stage carious-lesions.
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Affiliation(s)
- Agron Hoxha
- Oral Bioengineering, Barts and the London School of Medicine and Dentistry, Institute of Dentistry, Queen Mary University of London, Mile End Road, London E1 4NS, UK.
| | - David G Gillam
- Oral Bioengineering, Barts and the London School of Medicine and Dentistry, Institute of Dentistry, Queen Mary University of London, Mile End Road, London E1 4NS, UK.
| | - Amani Agha
- Oral Bioengineering, Barts and the London School of Medicine and Dentistry, Institute of Dentistry, Queen Mary University of London, Mile End Road, London E1 4NS, UK.
| | - Natalia Karpukhina
- Oral Bioengineering, Barts and the London School of Medicine and Dentistry, Institute of Dentistry, Queen Mary University of London, Mile End Road, London E1 4NS, UK.
| | - Andy J Bushby
- School of Engineering and Materials Science, Queen Mary University of London, London E1 4NS, UK.
| | - Mangala P Patel
- Oral Bioengineering, Barts and the London School of Medicine and Dentistry, Institute of Dentistry, Queen Mary University of London, Mile End Road, London E1 4NS, UK.
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Pengfei Y, Yuanxin X, Na Y, Yong A. Preparation of Uniform Highly Dispersed Mg–Al-LDHs and Their Adsorption Performance for Chloride Ions. Ind Eng Chem Res 2020. [DOI: 10.1021/acs.iecr.0c00747] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yang Pengfei
- School of Chemistry and Chemical Engineering, University of South China, Hengyang 421001, China
- Hunan Province Engineering Research Center of Radioactive Control Technology in Uranium Mining and Metallurgy, and Hunan Province Engineering Technology Research Center of Uranium Tailings Treatment Technology, University of South China, Hengyang 421001, China
- Hunan Key Laboratory for the Design and Application of Actinide Complexes, Hengyang 421001, China
| | - Xu Yuanxin
- School of Chemistry and Chemical Engineering, University of South China, Hengyang 421001, China
- Hunan Key Laboratory for the Design and Application of Actinide Complexes, Hengyang 421001, China
| | - Yin Na
- School of Chemistry and Chemical Engineering, University of South China, Hengyang 421001, China
- Hunan Key Laboratory for the Design and Application of Actinide Complexes, Hengyang 421001, China
| | - Ai Yong
- School of Chemistry and Chemical Engineering, University of South China, Hengyang 421001, China
- Hunan Key Laboratory for the Design and Application of Actinide Complexes, Hengyang 421001, China
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Ahmed A, Francis A, Liu N, Liu YY. A Prospect for Environmental Remediation of Perchlorate via Cost-Effective Pinus Leaves and Dandelion Flower Powder-based Layer Double Hydride (LDH) Sorbents. ARAB J CHEM 2020. [DOI: 10.1016/j.arabjc.2020.03.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
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Abo El-Reesh GY, Farghali AA, Taha M, Mahmoud RK. Novel synthesis of Ni/Fe layered double hydroxides using urea and glycerol and their enhanced adsorption behavior for Cr(VI) removal. Sci Rep 2020; 10:587. [PMID: 31953466 PMCID: PMC6969103 DOI: 10.1038/s41598-020-57519-4] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2019] [Accepted: 12/27/2019] [Indexed: 12/07/2022] Open
Abstract
Novel modified Ni/Fe layered double hydroxides with different morphology of spherical - like shape were fabricated via using urea as a ligand and glycerol (Ni/Fe LDH/GL) with Ni:Fe molar ratios of 2:1 by the simplest co -precipitation method. Also, for comparison purposes, Ni/Fe LDH was synthesized to be used as a control one. A suggested interpretation for the morphology change was also given. The materials were characterized by X-ray diffraction (XRD), The Fourier transform infrared (FT - IR) spectroscopy, field emission scanning electron microscopy (FESEM), EDX for elemental analysis, high resolution transmission electron microscopy (HRTEM), Brunauer, Emmett, and Teller (BET) equation, particle size distributions and Zeta potential measurements. In addition, the synthesized materials were used as adsorbents for removal of potassium dichromate from aqueous solutions under various experimental conditions. The adsorption of Cr (VI) was strongly pH dependant and the pHPZC was studied. Kinetic studies were evaluated through different models including, pseudo first and second orders, mixed 1, 2 orders, intra particle diffusion and Avrami models. For adsorption isotherms, two-parameter models (Langmuir, Freundlich and Temkin) and three parameter models (Sips, Langmuir-Freundlich and Tooth) were investigated showing maximum adsorption capacity of 50.43 mg/g and 136.05 mg/g for Ni/Fe LDH and Ni/Fe LDH/GL, respectively. Also, the effect of temperature was investigated at (23, 35, 45, 55 °C) and the thermodynamic parameters (∆H°, ∆S° and ∆G°) were calculated showing exothermic and spontaneous adsorption process. The effect of coexisting anions (Cl-, SO42- and HPO42-) and humic acid at different concentrations on the removal efficiency of dichromate ions was investigated. Chemical stability and recyclability of these adsorbents were also studied. The intermolecular hydrogen bonds formation between dichromate ion, urea, glycerol, LDH was explored by Monte Carlo simulation This study suggested that the modified Ni/Fe LDH/GL materials were promising nanoadsorbents for efficient potassium dichromate removal.
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Affiliation(s)
- Gehad Y Abo El-Reesh
- Chemistry Department, Faculty of Science, Beni-Suef University, Beni-Suef, Egypt
| | - Ahmed A Farghali
- Materials Science and nanotechnology Department, Faculty of Postgraduate Studies for Advanced Sciences (PSAS), Beni-Suef University, Beni-Suef, Egypt
| | - Mohamed Taha
- Materials Science and nanotechnology Department, Faculty of Postgraduate Studies for Advanced Sciences (PSAS), Beni-Suef University, Beni-Suef, Egypt
| | - Rehab K Mahmoud
- Chemistry Department, Faculty of Science, Beni-Suef University, Beni-Suef, Egypt.
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37
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Composites of polyethylene and layered cobalt hydroxide salts as potential ultraviolet radiation absorbers. Polym Bull (Berl) 2020. [DOI: 10.1007/s00289-019-02742-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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38
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Varga G, Szabados M, Kukovecz Á, Kónya Z, Varga T, Sipos P, Pálinkó I. Layered double alkoxides a novel group of layered double hydroxides without water content. MATERIALS RESEARCH LETTERS 2019. [DOI: 10.1080/21663831.2019.1700199] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Gábor Varga
- Department of Organic Chemistry, University of Szeged, Szeged, Hungary
- Materials and Solution Structure Research Group and Interdisciplinary Excellence Centre, Institute of Chemistry, University of Szeged, Szeged, Hungary
| | - Márton Szabados
- Department of Organic Chemistry, University of Szeged, Szeged, Hungary
- Materials and Solution Structure Research Group and Interdisciplinary Excellence Centre, Institute of Chemistry, University of Szeged, Szeged, Hungary
| | - Ákos Kukovecz
- Department of Applied and Environmental Chemistry, University of Szeged, Szeged, Hungary
| | - Zoltán Kónya
- Department of Applied and Environmental Chemistry, University of Szeged, Szeged, Hungary
- MTA-SZTE Reaction Kinetics and Surface Chemistry Research Group, University of Szeged, Szeged, Hungary
| | - Tamás Varga
- Department of Applied and Environmental Chemistry, University of Szeged, Szeged, Hungary
| | - Pál Sipos
- Materials and Solution Structure Research Group and Interdisciplinary Excellence Centre, Institute of Chemistry, University of Szeged, Szeged, Hungary
- Department of Inorganic and Analytical Chemistry, University of Szeged, Szeged, Hungary
| | - István Pálinkó
- Department of Organic Chemistry, University of Szeged, Szeged, Hungary
- Materials and Solution Structure Research Group and Interdisciplinary Excellence Centre, Institute of Chemistry, University of Szeged, Szeged, Hungary
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Hoxha A, Gillam DG, Bushby AJ, Agha A, Patel MP. Layered Double Hydroxide Fluoride Release in Dental Applications: A Systematic Review. Dent J (Basel) 2019; 7:dj7030087. [PMID: 31480648 PMCID: PMC6784472 DOI: 10.3390/dj7030087] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Revised: 08/17/2019] [Accepted: 08/20/2019] [Indexed: 11/16/2022] Open
Abstract
This systematic review appraises studies conducted with layered double hydroxides (LDHs) for fluoride release in dentistry. LDH has been used as antacids, water purification in removing excess fluoride in drinking water and drug delivery. It has great potential for controlled fluoride release in dentistry, e.g., varnishes, fissure sealants and muco-adhesive strips, etc. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Statement was followed with two reviewers performing a literature search using four databases: PubMed, Web of Science, Science Direct and Ovid Medline with no date restrictions. Studies including any LDH for ion/drug release in dentistry were included, while assessing the application of LDH and the value of the methodology, e.g., ion release protocol and the LDH production process. Results: A total of 258 articles were identified and four met the inclusion criteria. Based on two in vitro studies and one clinical study, LDH was previously studied in dental materials, such as dental composites and buccal muco-adhesive strips for fluoride release, with the latter studied in a clinical environment. The fourth study analysed LDH powder alone (without being incorporated into dental materials). It demonstrated fluoride release and the uptake of volatile sulphur compounds (VSC), which may reduce halitosis (malodour). Conclusion: LDHs incorporated in dental materials have been previously evaluated for fluoride release and proven to be clinically safe. LDHs have the potential to sustain a controlled release of fluoride (or other cariostatic ions) in the oral environment to prevent caries. However, further analyses of LDH compositions, and clinical research investigating any other cariostatic effects, are required.
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Affiliation(s)
- Agron Hoxha
- Oral Bioengineering, Barts and the London School of Medicine and Dentistry, Institute of Dentistry, Queen Mary University of London, Mile End Road, London E1 4NS, UK.
| | - David G Gillam
- Centre for Adult Oral Health, Barts and the London School of Medicine and Dentistry, Institute of Dentistry, Queen Mary University, New Road, London E1 2AD, UK
| | - Andy J Bushby
- School of Engineering and Materials Science, Queen Mary University of London, London E1 4NS, UK
| | - Amani Agha
- Oral Bioengineering, Barts and the London School of Medicine and Dentistry, Institute of Dentistry, Queen Mary University of London, Mile End Road, London E1 4NS, UK
| | - Mangala P Patel
- Oral Bioengineering, Barts and the London School of Medicine and Dentistry, Institute of Dentistry, Queen Mary University of London, Mile End Road, London E1 4NS, UK
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40
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Han X, Zhang S, Lu J, Ma Y, Fu N, Wu Y, Liu W, Mei D. Cu/Al Layered Double Hydroxide by Co-precipitation with High Anti-UV Performance in Waterborne Varnish. CHEM LETT 2019. [DOI: 10.1246/cl.190342] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Xiuxiu Han
- College of Chemistry and Chemical Engineering, Shanghai University of Engineering Science, Shanghai 201620, P. R. China
| | - Shuhua Zhang
- College of Chemistry and Chemical Engineering, Shanghai University of Engineering Science, Shanghai 201620, P. R. China
| | - Jingjing Lu
- Department of Plastics and Polymer Engineering Technology, Eastern Michigan University, Ypsilanti, MI 48197, USA
| | - Yingying Ma
- College of Chemistry and Chemical Engineering, Shanghai University of Engineering Science, Shanghai 201620, P. R. China
| | - Nengshuo Fu
- College of Chemistry and Chemical Engineering, Shanghai University of Engineering Science, Shanghai 201620, P. R. China
| | - Youtong Wu
- College of Chemistry and Chemical Engineering, Shanghai University of Engineering Science, Shanghai 201620, P. R. China
| | - Weijun Liu
- College of Mechanical and Automotive Engineering, Shanghai University of Engineering Science, Shanghai 201620, P. R. China
| | - Dajiang Mei
- College of Chemistry and Chemical Engineering, Shanghai University of Engineering Science, Shanghai 201620, P. R. China
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Nanocomposites of polyethylene and ternary (Mg + Zn/Al) layered double hydroxide modified with an organic UV absorber. JOURNAL OF POLYMER RESEARCH 2019. [DOI: 10.1007/s10965-019-1868-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Zhang Y, Yang J, Fan F, Qing B, Zhu C, Shi Y, Fan J, Deng X. Effect of Divalent Metals on the UV-Shielding Properties of M II/MgAl Layered Double Hydroxides. ACS OMEGA 2019; 4:10151-10159. [PMID: 31460107 PMCID: PMC6648468 DOI: 10.1021/acsomega.9b00721] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Accepted: 05/16/2019] [Indexed: 06/10/2023]
Abstract
Both the particle size and compositions have a strong influence on the UV-shielding performance of layered double hydroxides (LDHs), and they will interact with each other. To investigate the effects of divalent metal ions on the UV-shielding properties of layered double hydroxides (LDHs), MII/MgAl-CO3 LDHs (M = Mg, Co, Ni, Cu, or Zn) with the same primary and secondary particle size have been prepared and their UV-shielding performance have been studied in this work. The UV-vis spectra show that the ZnMgAl-LDHs exhibit the highest absorbance under the ultraviolet B and ultraviolet A rays among these LDH samples, but in the ultraviolet C region, the CuMgAl-LDHs show the highest absorbance and this result is in good accordance with the UV-shielding performance, which was examined by protecting the photocatalytic degradation of rhodamine B aqueous solution. Moreover, under UV rays, PP/ZnMgAl-LDH films show excellent resistance to UV aging, which can be attributed to the strong inhibition of ZnMgAl-LDHs during the production of free radicals in polypropene, as has been confirmed by electron spin resonance results.
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Affiliation(s)
- Yi Zhang
- Key Laboratory of Comprehensive and Highly Efficient
Utilization
of Salt Lake Resources and Qinghai Engineering and Technology Research Center
of Comprehensive Utilization of Salt Lake Resources, Chinese Academy of Sciences, Xining 810008, China
- University
of Chinese Academy of Science, Beijing 100049, China
| | - Jiaqi Yang
- Key Laboratory of Comprehensive and Highly Efficient
Utilization
of Salt Lake Resources and Qinghai Engineering and Technology Research Center
of Comprehensive Utilization of Salt Lake Resources, Chinese Academy of Sciences, Xining 810008, China
- University
of Chinese Academy of Science, Beijing 100049, China
| | - Faying Fan
- Key Laboratory of Comprehensive and Highly Efficient
Utilization
of Salt Lake Resources and Qinghai Engineering and Technology Research Center
of Comprehensive Utilization of Salt Lake Resources, Chinese Academy of Sciences, Xining 810008, China
| | - Binju Qing
- Key Laboratory of Comprehensive and Highly Efficient
Utilization
of Salt Lake Resources and Qinghai Engineering and Technology Research Center
of Comprehensive Utilization of Salt Lake Resources, Chinese Academy of Sciences, Xining 810008, China
| | - Chaoliang Zhu
- Key Laboratory of Comprehensive and Highly Efficient
Utilization
of Salt Lake Resources and Qinghai Engineering and Technology Research Center
of Comprehensive Utilization of Salt Lake Resources, Chinese Academy of Sciences, Xining 810008, China
| | - Yifei Shi
- Key Laboratory of Comprehensive and Highly Efficient
Utilization
of Salt Lake Resources and Qinghai Engineering and Technology Research Center
of Comprehensive Utilization of Salt Lake Resources, Chinese Academy of Sciences, Xining 810008, China
| | - Jie Fan
- Key Laboratory of Comprehensive and Highly Efficient
Utilization
of Salt Lake Resources and Qinghai Engineering and Technology Research Center
of Comprehensive Utilization of Salt Lake Resources, Chinese Academy of Sciences, Xining 810008, China
| | - Xiaochuan Deng
- Key Laboratory of Comprehensive and Highly Efficient
Utilization
of Salt Lake Resources and Qinghai Engineering and Technology Research Center
of Comprehensive Utilization of Salt Lake Resources, Chinese Academy of Sciences, Xining 810008, China
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Parashar S, Khare S. Supported transition metal catalysts of Cu(II), Mn(II) and Co(II): synthesis, characterization, and catalytic behavior. REACTION KINETICS MECHANISMS AND CATALYSIS 2019. [DOI: 10.1007/s11144-019-01559-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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44
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Structural reconstruction of mechanochemically disordered CaFe-layered double hydroxide. APPLIED CLAY SCIENCE 2019. [DOI: 10.1016/j.clay.2019.03.033] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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45
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Szabados M, Kónya Z, Kukovecz Á, Sipos P, Pálinkó I. Ultrasonically-assisted mechanochemical synthesis of zinc aluminate spinel from aluminium-rich layered double hydroxide. J SOLID STATE CHEM 2019. [DOI: 10.1016/j.jssc.2019.02.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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46
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Preparation of LDHs Based on Bittern and Its Flame Retardant Properties in EVA/LDHs Composites. ADVANCES IN POLYMER TECHNOLOGY 2019. [DOI: 10.1155/2019/4682164] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Bittern, as a byproduct of salt manufacture, is abundant in China. The researches and developments for seawater bittern have mainly focused on the reuse of magnesium, calcium, lithium, and boron. However, the utilization rate is less than 20%. The large amount of unused bittern has become a challenge that attracts much attention in academic and industry areas. In this paper, three kinds of layered double hydroxides (LDHs) were synthesized from bittern using a coprecipitation method and characterized by X-ray diffraction (XRD). The XRD results showed that the three kinds of LDHs(MgAl-LDHs, MgFe-LDHs and MgAlFe-LDHs) were successfully synthesized. Then, the flame retardant properties and thermal properties of the three LDHs in ethylene vinyl acetate (EVA)/LDHs composites had been tested by cone calorimeter test (CCT), limiting oxygen index (LOI), smoke density test (SDT), and thermogravimetry-Fourier transform infrared spectrometry (TG-IR). The CCT results showed that the heat release rate (HRR) of all three kinds of EVA/LDHs composites significantly decreased compared with that of pure EVA, and the EVA/MgAl-LDHs composites had the lowest PHRR value of 222.65 kW/m2. The LOI results showed that EVA/MgAl-LDHs composites had the highest LOI value of 29.8%. The SDT results indicated that MgAl-LDHs were beneficial to smoke suppression. TG-IR results showed that EVA/MgAl-LDHs composites had a better thermal stability.
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Zhu H, Huang X, Wang Z, Kong L, Chen M, Wang F. The remarkably improved filler dispersion and performance of SSBR/BR by core–shell structure SiO2@LDH nanocomposites. SN APPLIED SCIENCES 2019. [DOI: 10.1007/s42452-019-0324-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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48
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Zhang Q, Guo Y, Marek AA, Verney V, Leroux F, Tang P, Li D, Feng Y. Design, fabrication and anti-aging behavior of a multifunctional inorganic–organic hybrid stabilizer derived from co-intercalated layered double hydroxides for polypropylene. Inorg Chem Front 2019. [DOI: 10.1039/c9qi00601j] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The concomitant presence of HALS/DBHP co-intercalated within the LDH structure strongly improved the anti-aging performance of PP, which opens the pathway for potential future research of high-performance PP associated with hybrid fillers.
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Affiliation(s)
- Qian Zhang
- State Key Laboratory of Chemical Resource Engineering
- Beijing Engineering Center for Hierarchical Catalysts
- Beijing University of Chemical Technology
- Beijing 100029
- China
| | - Yixuan Guo
- State Key Laboratory of Chemical Resource Engineering
- Beijing Engineering Center for Hierarchical Catalysts
- Beijing University of Chemical Technology
- Beijing 100029
- China
| | - Adam A. Marek
- Universite Clermont Auvergne
- Institut de Chimie de Clermont-Ferrand ICCF
- UMR-CNRS 6296
- F 63171 Aubière
- France
| | - Vincent Verney
- Universite Clermont Auvergne
- Institut de Chimie de Clermont-Ferrand ICCF
- UMR-CNRS 6296
- F 63171 Aubière
- France
| | - Fabrice Leroux
- Universite Clermont Auvergne
- Institut de Chimie de Clermont-Ferrand ICCF
- UMR-CNRS 6296
- F 63171 Aubière
- France
| | - Pinggui Tang
- State Key Laboratory of Chemical Resource Engineering
- Beijing Engineering Center for Hierarchical Catalysts
- Beijing University of Chemical Technology
- Beijing 100029
- China
| | - Dianqing Li
- State Key Laboratory of Chemical Resource Engineering
- Beijing Engineering Center for Hierarchical Catalysts
- Beijing University of Chemical Technology
- Beijing 100029
- China
| | - Yongjun Feng
- State Key Laboratory of Chemical Resource Engineering
- Beijing Engineering Center for Hierarchical Catalysts
- Beijing University of Chemical Technology
- Beijing 100029
- China
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49
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Szadkowski B, Marzec A, Rybiński P, Maniukiewicz W, Zaborski M. Aluminum-Magnesium Hydroxycarbonate/Azo Dye Hybrids as Novel Multifunctional Colorants for Elastomer Composites. Polymers (Basel) 2018; 11:E43. [PMID: 30960027 PMCID: PMC6401992 DOI: 10.3390/polym11010043] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 12/20/2018] [Accepted: 12/24/2018] [Indexed: 12/02/2022] Open
Abstract
This study presents the preparation and characterization of new organic-inorganic pigments based on aluminum-magnesium hydroxycarbonate (LH) and azo dyes. Solvent resistance studies, XRD, SEM, and TGA confirmed the successful formation of hybrid pigments, which were characterized in terms of their physicochemical properties. The new hybrid pigments were applied in acrylonitrile-butadiene (NBR) and ethylene-propylene (EPM) rubber composites and cured with sulfur and peroxide curing systems, respectively. The mechanical properties, dispersion quality, and flame-retardant properties of the NBR/hybrid and EPM/hybrid pigment composites were determined by dynamic mechanical analysis (DMA), SEM, and microscale combustion calorimetry (MCC). Complex experimental investigations revealed that the layered nature of hybrid pigments could improve the barrier ability and flame retardancy of elastomer composites. In comparison to unmodified aluminum-magnesium hydroxycarbonate, the modified LH dye structures contributed to significantly decrease the heat release rate and the total heat release of the NBR and EPM composites, offering a new approach to imparting low flammability to elastomer materials.
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Affiliation(s)
- Bolesław Szadkowski
- Institute of Polymer and Dye Technology, Faculty of Chemistry, Lodz University of Technology, Stefanowskiego 12/16, 90-924 Lodz, Poland.
| | - Anna Marzec
- Institute of Polymer and Dye Technology, Faculty of Chemistry, Lodz University of Technology, Stefanowskiego 12/16, 90-924 Lodz, Poland.
| | - Przemysław Rybiński
- Department of Environmental Protection and Modeling, The Jan Kochanowski University, Świętokrzyska 15, 25-406 Kielce, Poland.
| | - Waldemar Maniukiewicz
- Institute of General and Ecological Chemistry, Lodz University of Technology, Zeromskiego 116, 90-924 Lodz, Poland.
| | - Marian Zaborski
- Institute of Polymer and Dye Technology, Faculty of Chemistry, Lodz University of Technology, Stefanowskiego 12/16, 90-924 Lodz, Poland.
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50
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Zhang Q, Gu Q, Leroux F, Tang P, Li D, Feng Y. Co-intercalated layered double hydroxides as thermal and photo-oxidation stabilizers for polypropylene. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2018; 9:2980-2988. [PMID: 30591846 PMCID: PMC6296430 DOI: 10.3762/bjnano.9.277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/22/2018] [Accepted: 11/16/2018] [Indexed: 06/09/2023]
Abstract
An elegant and efficient approach consisting in the co-intercalation of stabilizing molecular anions is described here. The thermal stabilizer calcium diethyl bis[[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methyl]phosphonate] (Irganox 1425, MP-Ca) and a photo-oxidation stabilizer (hindered amine light stabilizer, HALS) are co-intercalated into the interlayer regions of layered double hydroxides (LDH) in a one-step coprecipitation. These hybrid organic-inorganic materials are successively dispersed in polypropylene to form H n M n '-Ca2Al/PP composite films (with H = HALS and M = MP) through a solvent casting method. The corresponding crystalline structure, chemical composition, morphology as well as the resistance against thermal aging and photo-oxidation are carefully investigated by various techniques. The results show that the powdered H n M n '-Ca2Al-LDHs hybrid materials have a much higher thermal stability than MP-Ca and HALS before intercalation. In addition, the H n M n '-Ca2Al/PP composites exhibit a higher overall resistance against thermal degradation and photo-oxidation compared to LDHs intercalated with only HALS or MP. This underlines the benefit of the co-intercalation. The co-intercalated LDH materials pave a new way in designing and fabricating high-performance multifunctional additives for polymers.
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Affiliation(s)
- Qian Zhang
- State Key Laboratory of Chemical Resource Engineering, Beijing Engineering Center for Hierarchical Catalysts, Beijing University of Chemical Technology, No. 15 Beisanhuan East Road, Beijing 100029, China
| | - Qiyu Gu
- State Key Laboratory of Chemical Resource Engineering, Beijing Engineering Center for Hierarchical Catalysts, Beijing University of Chemical Technology, No. 15 Beisanhuan East Road, Beijing 100029, China
| | - Fabrice Leroux
- Université Clermont Auvergne, Institut de Chimie de Clermont-Ferrand ICCF, UMR-CNRS 6296, F 63171 Aubière, France
| | - Pinggui Tang
- State Key Laboratory of Chemical Resource Engineering, Beijing Engineering Center for Hierarchical Catalysts, Beijing University of Chemical Technology, No. 15 Beisanhuan East Road, Beijing 100029, China
| | - Dianqing Li
- State Key Laboratory of Chemical Resource Engineering, Beijing Engineering Center for Hierarchical Catalysts, Beijing University of Chemical Technology, No. 15 Beisanhuan East Road, Beijing 100029, China
| | - Yongjun Feng
- State Key Laboratory of Chemical Resource Engineering, Beijing Engineering Center for Hierarchical Catalysts, Beijing University of Chemical Technology, No. 15 Beisanhuan East Road, Beijing 100029, China
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