Articles de revues : « MALEIC ANHYDRIDE HYDROGEL »

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Filho, Cesar M. C., Pedro V. A. Bueno, Alan F. Y. Matsushita, Bruno H. Vilsinski, Adley F. Rubira, Edvani C. Muniz, Dina M. B. Murtinho et Artur J. M. Valente. « Uncommon Sorption Mechanism of Aromatic Compounds onto Poly(Vinyl Alcohol)/Chitosan/Maleic Anhydride-β-Cyclodextrin Hydrogels ». Polymers 12, n^o 4 (10 avril 2020) : 877. http://dx.doi.org/10.3390/polym12040877.

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Aromatic hydrocarbons are extensive environmental pollutants occurring in both water and air media, and their removal is a priority effort for a healthy environment. The use of adsorbents is among the several strategies used for the remediation of these compounds. In this paper, we aim the synthesis of an amphiphilic hydrogel with the potential for the simultaneous sorption of a set of monocyclic and polycyclic aromatic hydrocarbons associated with toxicity effects in humans. Thus, we start by the synthesis of a copolymer-based in chitosan and β-cyclodextrin previously functionalized with the maleic anhydride. The presence of β-cyclodextrin will confer the ability to interact with hydrophobic compounds. The resulting material is posteriorly incorporated in a cryogel of poly(vinyl alcohol) matrix. We aim to improve the amphiphilic ability of the hydrogel matrix. The obtained hydrogel was characterized by swelling water kinetics, thermogravimetric analysis, rheological measurements, and scanning electron microscopy. The sorption of aromatic hydrocarbons onto the gel is characterized by pseudo-first-order kinetics and Henry isotherm, suggesting a physisorption mechanism. The results show that the presence of maleic anhydride-β-cyclodextrin and chitosan into hydrogels leads to an increase in the removal efficiency of the aromatic compounds. Additionally, the capacity of this hydrogel for removing these pollutants from a fossil fuel sample has also been tested.

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Zhang, Ting, Nan Zheng, Jianfang Luo, Huiling Cai, Yanghao Li, Jia Zhai et Xinyi Peng. « Thermo-sensitive Hydrogel Incorporating Maleic Anhydride Modified Microcrystalline Cellulose ». IOP Conference Series : Earth and Environmental Science 446 (21 mars 2020) : 022055. http://dx.doi.org/10.1088/1755-1315/446/2/022055.

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Ronca, Alfredo, Ugo D’Amora, Maria Raucci, Hai Lin, Yujiang Fan, Xingdong Zhang et Luigi Ambrosio. « A Combined Approach of Double Network Hydrogel and Nanocomposites Based on Hyaluronic Acid and Poly(ethylene glycol) Diacrylate Blend ». Materials 11, n^o 12 (4 décembre 2018) : 2454. http://dx.doi.org/10.3390/ma11122454.

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In this study, an innovative polymer blend, based on double network (DN) approach, has been developed by integrating a poly(ethylene glycol) diacrylate (PEGDA) network into a chemically modified hyaluronic acid sodium salt (HAs) hydrogel matrix. Here, the HAs was chemically functionalized with photocrosslinkable moieties by reacting with maleic anhydride (MAA) to obtain a maleated hyaluronic acid (MaHA). Furthermore, nanocomposite DN hydrogels were suitably prepared by physical blending of hydroxyapatite nanoparticles (HAp), obtained by sol-gel synthesis, within the hydrogel. Physico-chemical, thermal, morphological and mechanical analyses were performed. Results showed enhanced mechanical properties and a homogenous microstructure as highlighted by mechanical and morphological investigations. This suggests that nanocomposite DN hydrogels are promising candidates for biomedical applications.

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Hrib, Jakub, Eva Chylikova Krumbholcova, Miroslava Duskova-Smrckova, Radka Hobzova, Jakub Sirc, Martin Hruby, Jiri Michalek, Jiri Hodan, Petr Lesny et Roman Smucler. « Hydrogel Tissue Expanders for Stomatology. Part II. Poly(styrene-maleic anhydride) Hydrogels ». Polymers 11, n^o 7 (26 juin 2019) : 1087. http://dx.doi.org/10.3390/polym11071087.

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Self-inflating soft tissue expanders represent a valuable modality in reconstructive surgery. For this purpose, particularly synthetic hydrogels that increase their volume by swelling in aqueous environment are used. The current challenge in the field is to deliver a material with a suitable protracted swelling response, ideally with an induction period (for sutured wound healing) followed by a linear increase in volume lasting several days for required tissue reconstruction. Here, we report on synthesis, swelling, thermal, mechanical and biological properties of novel hydrogel tissue expanders based on poly(styrene-alt-maleic anhydride) copolymers covalently crosslinked with p-divinylbenzene. The hydrogels exerted hydrolysis-driven swelling response with induction period over the first two days with minimal volume change and gradual volume growth within 30 days in buffered saline solution. Their final swollen volume reached more than 14 times the dry volume with little dependence on the crosslinker content. The mechanical coherence of samples during swelling and in their fully swollen state was excellent, the compression modulus of elasticity being between 750 and 850 kPa. In vitro cell culture experiments and in vivo evaluation in mice models showed excellent biocompatibility and suitable swelling responses meeting thus the application requirements as soft tissue expanders.

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Chi, Zheng, Chenchen Ma, Ziyuan He, Zihan Ma, Xuegang Chen et Zhaoge Huang. « A Supramolecular Hydrogel Based on Copolymers of Acrylic Acid and Maleic Anhydride Derivatives with Terpyridine Motifs ». Polymers 14, n^o 14 (13 juillet 2022) : 2857. http://dx.doi.org/10.3390/polym14142857.

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A kind of terpyridine derivative (NH2-Tpy) in which the amino was incorporated by a short alkyl chain was synthesized. Through grafting of terpyridine units into the hydrophilic copolymers of maleic anhydride and acrylic acid PAAMa via the reaction of the amino groups in NH2-Tpy and the maleic anhydride units, a series of gelator polymers—P1, P2, and P3—containing different contents of terpyridine units was synthesized. Under coordination of Ni2+ and terpyridine ligands in linear polymers, the supramolecular hydrogels H1, H2, and H3 with different cross-linking degrees were prepared. The linear polymers P1–P3 had a strong absorption peak at about 290 nm in the UV-vis spectra which was attributed to π–π* transition, and there was a new peak at about 335 nm led by the metal-to-ligands charge transfer (MLCT) when coordinated with Ni2+ ions. According to the rheological behaviors, the storage modulus (G′) was larger than the loss modulus (G′′). These hydrogels showed typical gel-like characteristics when the terpyridine content of the hydrogels exceeded 10%, and the hydrogels showed liquid-like characteristics when the terpyridine content of the hydrogels was less than 7%. The results of the micromorphological investigation of the xerogels from SEM illustrated the metal–terpyridine coordination cross-linking could have an important influence on the microstructures of the resulting hydrogels. Furthermore, these hydrogels based on supramolecular cross-links exhibited reversible solution–gel transition at different environmental temperatures. At the same time, the equilibrium swelling of the supramolecular hydrogels was 8.0–12.3 g/g, which increased with the decrease in the content of the terpyridine units in the resulting hydrogels.

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Eskhan, Asma, et Fawzi Banat. « Removal of Oil from Water by Calcium Alginate Hydrogel Modified with Maleic Anhydride ». Journal of Polymers and the Environment 26, n^o 7 (24 janvier 2018) : 2901–16. http://dx.doi.org/10.1007/s10924-018-1188-5.

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Liu, Xinxin, Tao Song, Minmin Chang, Ling Meng, Xiaohui Wang, Runcang Sun et Junli Ren. « Carbon Nanotubes Reinforced Maleic Anhydride-Modified Xylan-g-Poly(N-isopropylacrylamide) Hydrogel with Multifunctional Properties ». Materials 11, n^o 3 (28 février 2018) : 354. http://dx.doi.org/10.3390/ma11030354.

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Kusumaningsih, Triana, Abu Masykur, Aulia Syifa Aninditha et Maryam Rahmi Utami. « Preparation and Characterization of PVA/Na-CMC Hydrogel from OPEFB Cross-Linked by Maleic Anhydride ». EduChemia (Jurnal Kimia dan Pendidikan) 7, n^o 1 (30 janvier 2022) : 36. http://dx.doi.org/10.30870/educhemia.v7i1.12637.

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Bernert, Dominika B., Indra Böhm, Kathrin Isenbügel, Lisa Schönenberg et Helmut Ritter. « Hydrophobically modified poly[(divinyl ether)-co -(maleic anhydride)] : interactions with cyclodextrin derivatives and hydrogel formation ». Polymer International 61, n^o 3 (5 janvier 2012) : 413–17. http://dx.doi.org/10.1002/pi.3216.

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Kim, Su-Hwan, Hak Rae Lee, Seung Jung Yu, Min-Eui Han, Doh Young Lee, Soo Yeon Kim, Hee-Jin Ahn et al. « Hydrogel-laden paper scaffold system for origami-based tissue engineering ». Proceedings of the National Academy of Sciences 112, n^o 50 (30 novembre 2015) : 15426–31. http://dx.doi.org/10.1073/pnas.1504745112.

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In this study, we present a method for assembling biofunctionalized paper into a multiform structured scaffold system for reliable tissue regeneration using an origami-based approach. The surface of a paper was conformally modified with a poly(styrene-co-maleic anhydride) layer via initiated chemical vapor deposition followed by the immobilization of poly-l-lysine (PLL) and deposition of Ca2+. This procedure ensures the formation of alginate hydrogel on the paper due to Ca2+ diffusion. Furthermore, strong adhesion of the alginate hydrogel on the paper onto the paper substrate was achieved due to an electrostatic interaction between the alginate and PLL. The developed scaffold system was versatile and allowed area-selective cell seeding. Also, the hydrogel-laden paper could be folded freely into 3D tissue-like structures using a simple origami-based method. The cylindrically constructed paper scaffold system with chondrocytes was applied into a three-ring defect trachea in rabbits. The transplanted engineered tissues replaced the native trachea without stenosis after 4 wks. As for the custom-built scaffold system, the hydrogel-laden paper system will provide a robust and facile method for the formation of tissues mimicking native tissue constructs.

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Hu, Rui, Yao Li et Erlei Yu. « Glycidyl methacrylate-phytic acid crosslinked maleic anhydride-β-cyclodextrin hydrogel as an efficient cationic dye adsorbent ». Polymer 283 (septembre 2023) : 126232. http://dx.doi.org/10.1016/j.polymer.2023.126232.

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Rezazadeh, Hanieh, Peyman Najafi Moghadam, Saeideh Ehsanimehr et Amir Reza Fareghi. « Synthesis of a new magnetic nanocomposite hydrogel based on poly(vinyl acetate-co-maleic anhydride)/melamine for efficient dye removal ». Journal of Elastomers & ; Plastics 52, n^o 1 (28 janvier 2019) : 70–89. http://dx.doi.org/10.1177/0095244318824380.

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In this work, we fabricated a novel magnetic nanocomposite hydrogel based on poly(vinyl acetate- co-maleic anhydride)/melamine. A simple one-pot method was applied to fabricate the nanocomposite, and its adsorption capacity was investigated using Congo red (CR) dye. Then, the effects of a variety of parameters such as adsorbent dosage, solution pH, initial dye concentration, and contact time on the efficiency of the adsorbent were evaluated. The optimal adsorption of CR on the adsorbent was observed at pH 5 with 10 mg adsorbent and 10 mg L−1 initial dye concentrations where the adsorption efficiency reached above 90%. The Langmuir model was applied for fitting the adsorption isotherm of CR obtained on the proposed nanocomposite hydrogel, and it was observed that the adsorption process most probably followed a pseudo-second-order kinetic model. The obtained results showed that the proposed nanocomposite adsorbent could be used in water treatment. It was characterized with different techniques including X-ray diffraction, Fourier transform infrared spectroscopy, field-emission scanning electron microscopy, vibrating sample magnetometer, and energy dispersive X-ray.

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Wang, Qidong, Meng Li, Tianming Cui, Rui Wu, Fangfang Guo, Mei Fu, Yuqian Zhu, Chensong Yang, Bingdi Chen et Guixin Sun. « A Novel Zwitterionic Hydrogel Incorporated with Graphene Oxide for Bone Tissue Engineering : Synthesis, Characterization, and Promotion of Osteogenic Differentiation of Bone Mesenchymal Stem Cells ». International Journal of Molecular Sciences 24, n^o 3 (31 janvier 2023) : 2691. http://dx.doi.org/10.3390/ijms24032691.

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Zwitterionic materials are widely applied in the biomedical field due to their excellent antimicrobial, non-cytotoxicity, and antifouling properties but have never been applied in bone tissue engineering. In this study, we synthesized a novel zwitterionic hydrogel incorporated with graphene oxide (GO) using maleic anhydride (MA) as a cross-linking agent by grafted L-cysteine (L-Cys) as the zwitterionic material on maleilated chitosan via click chemistry. The composition and each reaction procedure of the novel zwitterionic hydrogel were characterized via X-ray diffraction (XRD) and Fourier transformed infrared spectroscopy (FT-IR), while the morphology was imaged by scanning electron microscope (SEM). In vitro cell studies, CCK-8 and live/dead assay, alkaline phosphatase activity, W-B, and qRT-CR tests showed zwitterionic hydrogel incorporated with GO remarkably enhanced the osteogenic differentiation of bone mesenchymal stem cells (BMSCs); it is dose-dependent, and 2 mg/mL GO is the optimum concentration. In vivo tests also indicated the same results. Hence, these results suggested the novel zwitterionic hydrogel exhibited porous characteristics similar to natural bone tissue. In conclusion, the zwitterionic scaffold has highly biocompatible and mechanical properties. When GO was incorporated in this zwitterionic scaffold, the zwitterionic scaffold slows down the release rate and reduces the cytotoxicity of GO. Zwitterions and GO synergistically promote the proliferation and osteogenic differentiation of rBMSCs in vivo and in vitro. The optimal concentration is 2 mg/mL GO.

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Tang, Chunyi, Shuhai Ye et Haiqing Liu. « Electrospinning of poly(styrene-co-maleic anhydride) (SMA) and water-swelling behavior of crosslinked/hydrolyzed SMA hydrogel nanofibers ». Polymer 48, n^o 15 (juillet 2007) : 4482–91. http://dx.doi.org/10.1016/j.polymer.2007.05.041.

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Loth, Tina, Robert Hennig, Christian Kascholke, Rudi Hötzel et Michael C. Hacker. « Reactive and stimuli-responsive maleic anhydride containing macromers – multi-functional cross-linkers and building blocks for hydrogel fabrication ». Reactive and Functional Polymers 73, n^o 11 (novembre 2013) : 1480–92. http://dx.doi.org/10.1016/j.reactfunctpolym.2013.08.002.

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Cao, Shengguang, Binghuan Hu et Haiqing Liu. « Synthesis of pH-responsive crosslinked poly[styrene-co-(maleic sodium anhydride)] and cellulose composite hydrogel nanofibers by electrospinning ». Polymer International 58, n^o 5 (mai 2009) : 545–51. http://dx.doi.org/10.1002/pi.2565.

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Subramanian, Bhuvaneshwaran, Arun Prabhu Rameshbabu, Kuntal Ghosh, Pradeep K. Jha, Rakhi Jha, Selvakumar Murugesan, Santanu Chattopadhyay et al. « Impact of styrene maleic anhydride (SMA) based hydrogel on rat fallopian tube as contraceptive implant with selective antimicrobial property ». Materials Science and Engineering : C 94 (janvier 2019) : 94–107. http://dx.doi.org/10.1016/j.msec.2018.09.023.

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Shafaghi, Samira, Peyman Najafi Moghadam, Amir Reza Fareghi et Mohammad Mehdi Baradarani. « Synthesis and characterization of a drug-delivery system based on melamine-modified poly(vinyl acetate-co-maleic anhydride) hydrogel ». Journal of Applied Polymer Science 131, n^o 12 (23 janvier 2014) : n/a. http://dx.doi.org/10.1002/app.40389.

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Yin, Xiangchun, et Harald D. H. Stöver. « Hydrogel Microspheres Formed by Complex Coacervation of Partially MPEG-Grafted Poly(styrene-alt-maleic anhydride) with PDADMAC and Cross-Linking with Polyamines ». Macromolecules 36, n^o 23 (novembre 2003) : 8773–79. http://dx.doi.org/10.1021/ma034617n.

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Eskhan, Asma, Fawzi Banat, Munirasu Selvaraj et Mohammad Abu Haija. « Enhanced removal of methyl violet 6B cationic dye from aqueous solutions using calcium alginate hydrogel grafted with poly (styrene-co-maleic anhydride) ». Polymer Bulletin 76, n^o 1 (23 mai 2018) : 175–203. http://dx.doi.org/10.1007/s00289-018-2378-y.

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Ahmad Saffian, Harmaen, Kim Hyun-Joong, Paridah Md Tahir, Nor Azowa Ibrahim, Seng Hua Lee et Ching Hao Lee. « Effect of Lignin Modification on Properties of Kenaf Core Fiber Reinforced Poly(Butylene Succinate) Biocomposites ». Materials 12, n^o 24 (5 décembre 2019) : 4043. http://dx.doi.org/10.3390/ma12244043.

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In this study, the effects of lignin modification on the properties of kenaf core fiber reinforced poly(butylene succinate) biocomposites were examined. A weight percent gain (WPG) value of 30.21% was recorded after the lignin were modified with maleic anhydride. Lower mechanical properties were observed for lignin composites because of incompatible bonding between the hydrophobic matrix and the hydrophilic lignin. Modified lignin (ML) was found to have a better interfacial bonding, since maleic anhydrides remove most of the hydrophilic hydrogen bonding (this was proven by a Fourier-transform infrared (FTIR) spectrometer—a reduction of broadband near 3400 cm−1, corresponding to the –OH stretching vibration of hydroxyl groups for the ML samples). On the other hand, ML was found to have a slightly lower glass transition temperature, Tg, since reactions with maleic anhydride destroy most of the intra- and inter-molecular hydrogen bonds, resulting in a softer structure at elevated temperatures. The addition of kraft lignin was found to increase the thermal stability of the PBS polymer composites, while modified kraft lignin showed higher thermal stability than pure kraft lignin and possessed delayed onset thermal degradation temperature.

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Gao, Qing He, Yi Can Wang, Zhi Feng Hou, Hui Juan Qian, Yuan Zhang, Jing Liu et Xin Ping Chen. « Research on Synthesis Regularity of Epoxysuccinic Acid ». Applied Mechanics and Materials 316-317 (avril 2013) : 942–45. http://dx.doi.org/10.4028/www.scientific.net/amm.316-317.942.

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The yield of epoxysuccinic acid was obtained by determining the content of unreacted maleic anhydride and tartaric acid as a by-product in synthesis system. This method could calculate the yield of epoxysuccinic acid precisely and overcome the disadvantage of obtaining inpure product by recrystallization method. Epoxysuccinic Acid was synthesized using maleic anhydride as raw material, hydrogen peroxide as oxidizer and tungstate as catalyst. The effects of reaction temperature, reaction time, ratio of materials, dosage of oxidizer and catalyst on epoxidation and hydrolysis reaction was investigated. The results showed that the yield of epoxysuccinic acid was 88% when the reaction conditions were as follows: reaction temperature 65°C, reaction time 1.5h, catalyst dosage 3%(based on mass of maleic anhydride), molar ratio of sodium hydrate to maleic anhydride 2:1, mass ratio of hydrogen peroxide to maleic anhydride 1:1.

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Wei, Zhongjin, Fengshan Zhou, Sinan Chen et Hongxing Zhao. « Composition, Properties, and Utilization of Fumaric Acid Sludge By-Produced from Industrial Phthalic Anhydride Wastewater Treatment ». Polymers 14, n^o 23 (28 novembre 2022) : 5169. http://dx.doi.org/10.3390/polym14235169.

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To understand fumaric acid sludge (FAS) systematically and comprehensively and find out how to utilize it, we conducted a series of characterization analyses on FAS. Fourier transform infrared (FT-IR) Spectra shows that the main component of FAS is fumaric acids and also contains a small amount of silicate. The nuclear magnetic resonance hydrogen (1H-NMR) spectrum also shows that fumaric acid accounted for a large proportion of FAS. The X-ray diffraction (XRD) shows that the main phase in FAS is fumaric acid, and there is also a small amount of Kaliophilite. After gas chromatography and mass spectrometry (GC-MS) and pyrolysis gas chromatography and mass spectrometry (Py-GC-MS) analysis, it indicates that the possible volatiles and pyrolysis products in FAS are fumaric acid, maleic acid, maleic anhydride, phthalic acid, etc. In the test of Liquid chromatography and mass spectrometry (LC-MS), we determined the contents of phthalic acid, fumaric acid, and maleic acid in FAS. The detailed mass content of each component in FAS is as follows: phthalic acid is about 0.10–0.15%; maleic anhydride is about 0.40–0.80%; maleic acid is about 18.40–19.0%; fumaric acid is about 55.00–56.90%; succinic anhydride is about 0.06–0.08%; acrylic acid is about 0.06–0.08%; malic acid is about 0.90–1.00%; acetic acid is about 0.10–0.20%; silicate is about 0.25–0.30%; phthalic anhydride is about 0.20–0.30%; water is about 24.30–24.80%. The filtrate loss reducer (PAAF) used in oilwell drilling fluids synthesized by FAS not only has excellent temperature and complex saline resistance, the API filtration loss (FL) was only 13.2 mL/30 min in the complex saline based mud, but is also cost-effective.

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Shinzawa, Hideyuki, Aki Sugahara, Hideaki Hagihara, Junji Mizukado et Ryota Watanabe. « Fourier Transform Infrared Imaging Analysis of Interactions Between Polypropylene Grafted with Maleic Anhydride and Silica Spheres Using Two-Trace Two-Dimensional Correlation Mapping ». Applied Spectroscopy 75, n^o 8 (15 avril 2021) : 947–56. http://dx.doi.org/10.1177/00037028211007872.

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A technique for analyzing infrared imaging data based on two-trace two-dimensional (2T2D) correlation analysis is presented to extract pertinent information underlying spectroscopic imaging data. In 2T2D correlation mapping, each spectrum in hyperspectral data is individually compared with a reference spectrum to generate 2T2D asynchronous correlation intensity at the x- and y-coordinates on a 2T2D correlation map. Asynchronous correlation intensity develops only when the signal contribution from a certain species becomes even more significant in the sample spectrum compared with the reference spectrum. This feature can be advantageously utilized to examine molecular interaction or an intermediate form of the component present in a system of interest. 2T2D correlation mapping is examined using Fourier transform infrared imaging data of polymer composites based on polypropylene grafted with maleic anhydride melt-mixed with silica spheres. Infrared images derived by using conventional visualization based on a single wavenumber (i.e., 1713 cm−1) are dominated with the overwhelming infrared absorbance induced by the normal maleic anhydride species, making the identification of subtle but pertinent changes in the composite system difficult. A 2T2D correlation map derived from the maleic anhydride/silica spheres composite developed a significant asynchronous correlation intensity between the infrared bands at 1695 and 1713 cm−1 around a specific region on the map where the maleic anhydride and silica spheres coexist. On the other hand, such a correlation pattern becomes less acute when the silica spheres is modified with the octadecyldimethyl group to prevent the hydrogen bonding with the maleic anhydride. It thus revealed that the silanol groups on the surface of the silica spheres substantially interact with the maleic anhydride via the development of the hydrogen bonding.

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Fridrihsone, Velta, Juris Zoldners, Marite Skute, Laura Andze et Inese Filipova. « Cellulose Modification with Maleic Anhydride ». Materials Science Forum 1071 (18 octobre 2022) : 197–203. http://dx.doi.org/10.4028/p-g7t849.

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Cellulose modification is a challenge due to molecules characteristics – equatorial conformation, hydrogen bonds both withing molecule and among neighboring molecules etc. Esterification of cellulose hydroxyl groups (-OH) with dicarboxylic compounds is challenging. In presented study simple modification with maleic anhydride is performed in an anhydrous environment. Scanning electron microscopy reveals clean fibers of cellulose-maleic anhydride derivatives. FTIR proves unique peak at 1735cm-1 that corresponds to ester carbonyl groups. Titration of carboxylic (-COOH) groups solidifies that one part of anhydride has bonded with cellulose and other carboxylic groups is accessible for further development.

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Momeni, Ahmad R., Hamid Aliyan, Heidar Mombeini, Ahmad R. Massah et Hamid J. Naghash. « Aromatization of Hantzsch 1,4-Dihydropyridines with Urea-Hydrogen Peroxide/Maleic Anhydride ». Zeitschrift für Naturforschung B 61, n^o 3 (1 mars 2006) : 331–33. http://dx.doi.org/10.1515/znb-2006-0314.

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Caló, Enrica, Joao M. S. de Barros, Mar Fernández-Gutiérrez, Julio San Román, Lucy Ballamy et Vitaliy V. Khutoryanskiy. « Antimicrobial hydrogels based on autoclaved poly(vinyl alcohol) and poly(methyl vinyl ether-alt-maleic anhydride) mixtures for wound care applications ». RSC Advances 6, n^o 60 (2016) : 55211–19. http://dx.doi.org/10.1039/c6ra08234c.

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Vida, Norbert, Jiří Václavík et Petr Beier. « Synthesis and reactivity of aliphatic sulfur pentafluorides from substituted (pentafluorosulfanyl)benzenes ». Beilstein Journal of Organic Chemistry 12 (20 janvier 2016) : 110–16. http://dx.doi.org/10.3762/bjoc.12.12.

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Oxidation of 3- and 4-pentafluorosulfanyl-substituted anisoles and phenols with hydrogen peroxide and sulfuric acid provided a mixture of SF5-substituted muconolactone, maleic, and succinic acids. A plausible mechanism for the formation of the aliphatic SF5 compounds was presented and their chemical reactivity was investigated. SF5-substituted para-benzoquinone was synthesized; its oxidation led to an improved yield of 2-(pentafluorosulfanyl)maleic acid. The reaction of SF5-substituted maleic anhydride and para-benzoquinone with cyclopentadiene afforded the Diels–Alder adducts. Decomposition of 3-(pentafluorosulfanyl)muconolactone in acidic, neutral and basic aqueous media was investigated and the decarboxylation of 2-(pentafluorosulfanyl)maleic acid provided 3-(pentafluorosulfanyl)acrylic acid.

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Al-Dossary, Mona, Harihara Padhy, Feng Xu, Ali R. Behzad, Omar el Tall et Alexander Rothenberger. « Copper-based hydrogels with dicarboxylate spacer ligands for selective carbon dioxide separation applications ». New Journal of Chemistry 42, n^o 22 (2018) : 18242–51. http://dx.doi.org/10.1039/c8nj01997e.

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Dicarboxylate spacer ligands enhanced the rigidity, porosity, surface area, and CO₂/N₂ and CO₂/CH₄ selectivity of Cu²⁺-based poly(methyl vinyl ether-alt-maleic anhydride) hydrogels.

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Diyuk, O. A. « Synthesis and properties of VPO catalysts for oxidation of n-butane to maleic anhydride ». Catalysis and Petrochemistry, n^o 33 (2022) : 46–58. http://dx.doi.org/10.15407/kataliz2022.33.046.

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Bulk and supported vanadium-phosphorus oxide VPO catalysts were synthesized by traditional and barothermal methods. It was shown that the use of aerosil as a support for the VPO phase, depending on the time of its introduction into the reaction mixture. It can lead to the formation of catalyst precursor of vanadyl hydrogen phosphate VOHPO4 0.5H2O, or a phase of vanadyl pyrophosphate (VO)2P2O7 as already the catalytically active phase for selective oxidation of n-butane to maleic anhydride. The use of a modified aerosil gel formed from pyrogenic aerosol, as a support for the VPO phase, leads to the formation of VOHPO4∙0.5H2O phase. It has been found that the nature of support affects the features of formation of VOHPO4∙0.5H2O phase, in particular, the ratio of crystallographic planes in resulting VPO phase. The use of aerosil as a support leads to a decrease in the relative content of the basal plane, while use of aerosil gel leads to an increase in the relative content of the basal plane in applied VPO phase. The catalytic properties of bulk and supported VPO samples were studied in the selective oxidation of n-butane to maleic anhydride in standard (1.7 vol.%) and enriched (3.4 vol.%) n-butane mixtures. It has been found that in an enriched n-butane mixture for bulk samples, the n-butane conversion and selectivity for maleic anhydride are sharply reduced. It has been found that supported VPO samples have a higher specific rate of n-butane oxidation and higher productivity compared to bulk samples. It was shown that use of barothermal synthesis and aerosol gel as a support made it possible to increase the selectivity of maleic anhydride, which is associated with an increase in the relative content of the basal plane of VPO phase. The achieved improved catalytic properties of VPO catalysts supported with aerosol gel make recycling technology promising. This can make the production of maleic anhydride more economical.

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Sahb, Mohaned M., et Zeina M. Kadam. « Synthesis and Biological Activity of New Derivatives of Thiazolidine and Oxazepine-Linked to Pyridine Moieties ». INTERNATIONAL JOURNAL OF DRUG DELIVERY TECHNOLOGY 12, n^o 03 (30 juin 2022) : 947–51. http://dx.doi.org/10.25258/ijddt.12.3.03.

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This research includes reaction and condensation between substituted 4-aminopyridine and 4-(N, N-dimethyl amino benzaldehyde) to produce Schiff base derivative (3), the compound (3) was selected to react with a different compound such as Thioglycolic acid, Phthalic anhydride, and maleic anhydride, to produced new ring of Thiazolidine derivatives and oxazepine derivatives structures (4,5,6,7,8,9,10,11,12), respectively. The final compound was characterized the structure by Fourier transform-infrared spectroscopy, H-Nuclear magnetic resonance (H-NMR) in addition to the Carbon, Hydrogen, Nitrogen (CHN) analyzer. Biological activity has been considered for the final structures and achievements of multi drugs.

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Maranzana, Andrea, et Glauco Tonachini. « Mechanism of the Photochemical Isomerization and Oxidation of 2-Butenedial : A Theoretical Study ». Molecules 28, n^o 13 (26 juin 2023) : 4994. http://dx.doi.org/10.3390/molecules28134994.

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Under tropospheric conditions, 2-butenedial is photochemically removed to produce secondary organic aerosol. Upon solar irradiation in the lower troposphere, the main photochemical products are ketene-enol (a key intermediate product), furanones, and maleic anhydride. The oxidative reaction mechanism was studied using the multireference method CASSCF to explore the hypersurface of the two most accessible singlet excited states, and by DFT for the ground state. Photoisomerization of 2-butenedial in the first excited state directly produces ground state ketene-enol upon nonradiative relaxation. From this intermediate, furan-2-ol and successively 3H-furan-2-one and 5H-furan-2-one are formed. The cooperative effect of two water molecules is essential to catalyze the cyclization of ketene-enol to furan-2-ol, followed by hydrogen transfers to furanones. Two water molecules are also necessary to form maleic anhydride from furan-2-ol. For this last reaction, in which one extra oxygen must be acquired, we hypothesize a mechanism with singlet oxygen as the oxidant.

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Tamburini, Giulia, Carmen Canevali, Silvia Ferrario, Alberto Bianchi, Antonio Sansonetti et Roberto Simonutti. « Optimized Semi-Interpenetrated p(HEMA)/PVP Hydrogels for Artistic Surface Cleaning ». Materials 15, n^o 19 (28 septembre 2022) : 6739. http://dx.doi.org/10.3390/ma15196739.

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The synthesis of hydrogels that are based on poly-hydroxyethyl methacrylate, p(HEMA), network semi-interpenetrated with linear polyvinylpyrrolidone (PVP) was optimized in order to allow both a fast preparation and a high cleaning effectiveness of artistic surfaces. For this purpose, the synthesis parameters of the gel with PVP having a high molecular weight (1300 kDa) that were reported in the literature, were modified in terms of temperature, time, and crosslinker amount. In addition, the gel composition was modified by using PVP with different molecular weights, by changing the initiator and by adding maleic anhydride. The modified gels were characterized in terms of equilibrium water content (EWC), water uptake, conversion grade, and thermal properties by differential scanning calorimetry (DSC). The cleaning effectiveness of the gels was studied through the removal of copper salts from laboratory-stained specimens. Cleaning materials were characterized by electron paramagnetic resonance (EPR) spectroscopy, ultraviolet-visible (UV-Vis) spectroscopy, and inductively-coupled plasma-mass spectrometry (ICP-MS). Cleaning was assessed on marble specimens by color variation measurements. The gel synthesis is accelerated by using PVP 360 kDa. The addition of maleic anhydride in the p(HEMA)/PVP network allows the most effective removal of copper salt deposits from marble since it acts as a chelator towards copper ions.

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Klushin, Victor, Ekaterina Shabliy et Dmitry Petrenko. « Unsaturated Polyester Resins and Fiber-Reinforced Polymer Composites from Plant Biomass ». Key Engineering Materials 869 (octobre 2020) : 169–74. http://dx.doi.org/10.4028/www.scientific.net/kem.869.169.

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We are the first to report the synthesis of maleic acid in quantitative yield by oxidation of 5-hydroxymethyl furfural with hydrogen peroxide in the presence of sodium bicarbonate in an aqueous medium under ambient conditions without the using of toxic catalysts and solvents. 5-hydroxymethyl furfural and 2,5-furandicarboxylic acid have been prepared from hexose plant biomass. Based on maleic anhydride and 2,5-furandicarboxylic acid, unsaturated polyesters were synthesized for the first time from renewable raw materials only. A fiber-reinforced polymer composite based on these polyester resins have been prepared. Strength properties of carbon and glass fiber-reinforced polymer composites are 1.5 times superior to the strength of similar phthalic acid based composites.

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Müller, Christina, Michael Ansorge, Martin Espig, Stefan Zschoche, Jürgen Schiller et Tilo Pompe. « Covalent Binding of Maleic Anhydride Copolymer Monolayers to Polyacrylamide Hydrogels ». Macromolecular Chemistry and Physics 219, n^o 17 (9 août 2018) : 1800206. http://dx.doi.org/10.1002/macp.201800206.

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Jiang, Longwei, Yanlong Han, Xiangyi Meng, Yawen Xiao et Huajiang Zhang. « Cellulose Nanocrystals Reinforced Zein/Catechin/β-Cyclodextrin Inclusion Complex Nanoparticles Nanocomposite Film for Active Food Packaging ». Polymers 13, n^o 16 (17 août 2021) : 2759. http://dx.doi.org/10.3390/polym13162759.

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In this study, following the green, environmentally friendly and sustainable development strategy, cellulose nanocrystals (CNCs) were prepared through a solvent-free esterification reaction between microcrystalline cellulose and maleic anhydride, combined with subsequent ultrasonic treatment, and maleic-anhydride-modified CNC-reinforced zein/catechin/β-cyclodextrin inclusion complex nanoparticles nanocomposite films were prepared by a facile solution casting. The amount of CNCs in the film matrix was 0–8 wt%, and their effect on structural, physicochemical and functional properties of the resulting films were investigated. SEM images showed that the addition of CNCs made the microstructure of the film more smooth and uniform. The intermolecular hydrogen bonds between CNCs and film matrix were supported by FT-IR. XRD analysis also confirmed the appearance of a crystalline peak due to the existence of CNCs inside the films. The incorporation of CNCs significantly reduced water vapor permeability, water solubility and the swelling degree of the nanocomposite film, and also significantly increased tensile strength and elongation at break from 12.66 to 37.82 MPa and 4.5% to 5.2% (p < 0.05). Moreover, nanocomposite film packaging with CNCs can effectively inhibit the oxidation of soybean oil.

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Bettahar, Faiza, Fadila Bekkar, Leyre Pérez-Álvarez, Mohammed Issam Ferahi, Rachid Meghabar, José Luis Vilas-Vilela et Leire Ruiz-Rubio. « Tough Hydrogels Based on Maleic Anhydride, Bulk Properties Study and Microfiber Formation by Electrospinning ». Polymers 13, n^o 6 (22 mars 2021) : 972. http://dx.doi.org/10.3390/polym13060972.

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Hydrogels present a great number of advantages, such as their swelling capacity or their capability to mimic tissues, which make them very interesting biomaterials. However, one of their main disadvantages is their lack of good mechanical properties, which could limit some of their applications. Several strategies have been carried out to develop hydrogels with enhanced mechanical properties, but many of the suggested synthetic pathways to improve this property are expensive and time consuming. In this work, we studied an easy synthetic path to produce tough hydrogels based on different maleic anhydride copolymers crosslinked with polyethylenglycol. The effect of the comonomers in the mechanical properties has been studied, their excellent mechanical properties, good swelling behavior and thermal stability being remarkable. In addition, in order to evaluate their possible applications as scaffolds or in wound healing applications, microsized fibers have been fabricated by electrospinning.

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Tam, Le The. « MAGNETIC RESONANCE IMAGING (MRI) APPLICATION OF Fe3O4 BASED FERROFLUID SYNTHESIZED BY THERMAL DECOMPOSITION USING POLY (MALEIC ANHYDRIDE -ALT-1-OCTADECENE) (PMAO) ». Vietnam Journal of Science and Technology 56, n^o 1A (4 mai 2018) : 174. http://dx.doi.org/10.15625/2525-2518/56/1a/12520.

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The Fe3O4 fluid synthesis by thermal decomposition method carried out in organic solvents with high boiling temperatures disposes a possibility of creating high-quality nanoparticles with uniform particle size and high degree of crystallization. In this paper, Fe3O4 fluid was prepared by thermal decomposition using poly (maleic anhydride-alt-1-octadecene) (PMAO) as a phase transfer ligand. The crystalline structure, morphology and magnetic property of the as-prepared samples were thoroughly characterized. The results demonstrated that the magnetic Fe3O4 nanomaterial was formed in liquid phase with spinel single phase structure, average size of 13-16 nm, and high saturation magnetization (up to 70 emu/g). Iron oxide (Fe3O4) nanoparticles coated with biocompatible poly (maleic anhydride-alt-1-octadecene) (PMAO) were synthesized for use as an MRI (magnetic resonance imaging) contrast agent. The spin-lattice (T1) and the spin-spin (T2) relaxation times of the nuclear spins (hydrogen protons) in aqueous solutions of various concentrations of coated ferrite nanoparticles were determined using a nuclear magnetic resonance (NMR) spectrometer. The MRI image was detected with higher contrast in comparison with that before injecting. By comparing with the MRI images taken in T1 weighted the T2 weighted images are clearer. The MRI images of a rabbit taken by the T2 weighted which shows that our coated ferrite nanoparticles can be used as a T2 MRI contrast agent.

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Li, Lin, et Jin Kuk Kim. « THERMOREVERSIBLE CROSS-LINKING MALEIC ANHYDRIDE GRAFTED CHLOROBUTYL RUBBER WITH HYDROGEN BONDS (COMBINED WITH IONIC INTERACTIONS) ». Rubber Chemistry and Technology 87, n^o 3 (1 septembre 2014) : 459–70. http://dx.doi.org/10.5254/rct.14.86976.

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ABSTRACT Thermoreversible cross-linking polymers are designed based on reversible cross-linking bonds. These bonds are able to reversibly dissociate and associate upon the input of external energy, such as heat or light. Reprocessibility is possible for this kind of material. The objective was to thermoreversibly cross-link maleic anhydride grafted chlorobutyl rubber (MAH-g-CIIR) via a reaction with octadecylamine, with an excess to obtain amide-salts, which form both hydrogen bonds and ionic interactions. X-ray diffraction experiments showed the presence of microphase-separated aggregates that acted as physical cross-links for both the MAH-g-CIIR precursor and amide-salts. The tensile properties were improved by converting MAH-g-CIIR to amide-salts, because of the combination of hydrogen bonding and ionic interactions. The cross-linked materials could be repeatedly compression molded at 155 °C into homogeneous films. The differential scanning calorimetry curves and Fourier transform infrared spectra indicate that hydrogen bonds are of a thermoreversible nature, but the recovery of ionic bonds is impossible. After treatment with heating-cooling for up to three cycles, the tensile strength of the thermoreversible cross-linking CIIR was greatly reduced. The gradual reduction in the effectiveness of the ionic-hydrogen bonds is the major contribution to the reprocessibility of these materials.

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Rzaev, Zakir M. O., Güneri Akovali, E. Yu Kuliyeva et N. Yu Lezgiev. « Complex-radical copolymerization of vinylcyclohexyl ketones with maleic anhydride and N-p-tolylmaleimide ». Eurasian Chemico-Technological Journal 1, n^o 1 (14 avril 2016) : 17. http://dx.doi.org/10.18321/ectj343.

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<p>Some features of the formation and photochemical reactions of cyclohexylketone containing macromolecules including copolymers of vinylcyclohexyl ketone (VCHK) and its derivatives (V-a-Cl-CHK and V- d-C1-CHK) with maleic anhydride (MA) and N-p-tolylmaleimide (TMI) have been revealed. It has been established that keto-enol tautomerism is the only reaction realized in the vinylcyclohexylketone molecules having mobile hydrogen atom at a -position in the cyclohexane ring, enol form of which is formed by charge-transfer complexes with anhydride or imide of maleic acid as acceptor monomers. The kinetic parameters of these reactions, including complex-formation and copolymerization constants, as well as the ratios of chain growth rates for the participation of monomeric charge-transfer complexes and free monomers, are all determined. It is shown that an alternative copolymerization is realized with the monomer systems containing VCHK and V- d -C1-CHK, which are carried out through a complex-mechanism due to the keto-enol tautomerism; while random copolymer enriched with vinyl ketone units is formed with the system containing oc-substituted VCHK. It is found that characteristics of photochemical reactions of alternating copolymer synthesized depend on the type of substitutation in the vinyl ketone molecule; unlink VCHK-MA(TMI) and V-d-C1-CHK-MA(TMI) copolymers case which easily crosslink upon UVirradiation, and the N-substituted derivatives of these copolymers which decompose under similar condition.</p>

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Karimi, Ali Reza, Leila Rahimi, Farnaz Azadikhah et Sahar Ghadimi. « Preparation and lower critical solution temperature behavior investigation of new thermoresponsive poly(N-isopropylacrylamide-co-phthalocyanine) magnetic nanocomposites containing phthalocyanine-coated Fe3O4 hybrid ». Canadian Journal of Chemistry 94, n^o 8 (août 2016) : 723–31. http://dx.doi.org/10.1139/cjc-2016-0109.

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New thermoresponsive poly(N-isopropyl acrylamide-co-phthalocyanine) magnetic nanocomposites were prepared by in situ dispersion polymerization. 4-Nitrophthalic acid and CoCl2 were employed to synthesize tetranitrophthalocyanine and then it was converted to tetraaminophthalocyanine by sodium sulfide. The cobalt tetra(N-carbonylacrylic)aminophthalocyanine monomer was obtained by reaction of tetraaminophthalocyanine with maleic anhydrid. N-isopropylacrylamide as the main monomers, N,N′-methylenebisacrylamide as the cross-linker, poly(N-vinylpyrrolidone) as the steric stabilizer, potassium persulfate as the initiator, and new Fe-phthalocyanine oligomer/Fe3O4 nanohybrid particles (FePc/Fe3O4) as nanoparticles were used. The magnetite nanocomposites were characterized by Fourier-transform infrared spectrum, X-ray diffraction spectroscopy, scanning electron microscopy, thermogravimetric analysis, vibrating sample magnetometer, and differential scanning calorimetry. The results showed that the lower critical solution temperatures of the hydrogel nanocomposits were influenced by the content of FePc/Fe3O4 hybrid nanoparticles. The lower critical solution temperatures of the magnetic hydrogel nanocomposites F3 and F4 were at about 34 and 40 °C. The results show that the increase of FePc/Fe3O4 nanoparticle content caused the LCSTs of the hydrogels to increase. FePc/Fe3O4 nanoparticles were prepared from 4,4′-isopropyliden-bis-dioxydiphthalonitrile and FeCl3·6H2O via the solvothermal route. The sizes of nanoparticles were determined by scanning electron microscopy. They are spherical in shape and the average size of them is between 30 and 70 nm.

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Andrés, Gabriel O., O. Fernando Silva et Rita H. de Rossi. « Hydrolysis of aryl hydrogen maleate esters mediated by cyclodextrins Effect on the intramolecular catalysis ». Canadian Journal of Chemistry 83, n^o 9 (1 septembre 2005) : 1281–86. http://dx.doi.org/10.1139/v05-144.

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Kinetic studies of the hydrolysis of Z-aryl hydrogen maleates (Z = H, p-CH3, m-CH3, p-Cl, m-Cl) were carried out in the presence and absence of hydroxypropyl-β-cyclodextrin (HPCD) at variable pH from 1.00 to 3.00. The reaction involves the formation of maleic anhydride as an intermediate and the rate of its formation is strongly dependent on the pH. This is because the neighboring carboxylate group is a better catalyst than the carboxylic group. The rate constant for the formation of maleic anhydride decreases as the HPCD concentration increases in a nonlinear fashion. The results were interpreted in terms of the formation of a 1:1 inclusion complex of the esters with HPCD. The neutral (HA) and anionic (A) species of the substrate have different association constants (K[Formula: see text] and K[Formula: see text]). In all cases studied, K[Formula: see text] is higher than K[Formula: see text] for the same substrate. This difference is responsible for a decrease in the amount of the anionic substrate (reactive species) in the presence of HPCD, which results in a diminution of the observed rate constant. Besides, the rate constant for the reaction of the complexed substrate is smaller than that in the bulk solution indicating that the transition state of the cyclodextrin mediated reaction is less stabilized than the anionic substrate. The values of ΔΔG are almost independent of the substituent on the aryl ring and range within 0.48 and 1.05 kcal mol1 (1 cal = 4.184 J). There is no correlation between KTS and the association constant of the substrate indicating that the factors stabilizing the transition state are different from those that stabilize the substrate. Key words: cyclodextrins, intramolecular catalysis, hydrolysis, inhibition.

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Simsek, Okan, Muharrem Dincer, Necmi Dege, Eiad Saif, Ibrahim Yilmaz et Alaaddin Cukurovali. « Crystal structure and Hirshfeld surface analysis of (Z)-4-{[4-(3-methyl-3-phenylcyclobutyl)thiazol-2-yl]amino}-4-oxobut-2-enoic acid ». Acta Crystallographica Section E Crystallographic Communications 78, n^o 2 (7 janvier 2022) : 120–24. http://dx.doi.org/10.1107/s2056989022000032.

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The title cyclobutyl compound, C18H18N2O3S, was synthesized by the interaction of 4-(3-methyl-3-phenylcyclobutyl)thiazol-2-amine and maleic anhydride, and crystallizes in the orthorhombic space group P212121 with Z′ = 1. The molecular geometry is partially stabilized by an intramolecular N—H...O hydrogen bond forming an S 1 1(7) ring motif. The molecule is non-planar with a dihedral angle of 88.29 (11)° between the thiazole and benzene rings. In the crystal, the molecules are linked by O—H...N hydrogen bonds, forming supramolecular ribbons with C 1 1(9) chain motifs. To further analyze the intermolecular interactions, a Hirshfeld surface analysis was performed. The results indicate that the most important contributions to the overall surface are from H...H (43%), C...H (18%), O...H (17%) and N...H (6%), interactions.

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Anugrah, D. S. B., M. P. Patil, X. Li, C. M. Q. Le, K. Ramesh, G.-D. Kim, K. Hyun et K. T. Lim. « Click-cross-linked, doxorubicin-loaded hydrogels based on poly(styrene-alt-maleic anhydride) ». Express Polymer Letters 14, n^o 3 (2020) : 248–60. http://dx.doi.org/10.3144/expresspolymlett.2020.21.

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Can, Hatice Kaplan, Zakir M. O. Rzaev et Ali Güner. « Hydrogen (H)-complex formation of maleic anhydride–acrylic acid (methyl acrylate) monomer system ». Journal of Molecular Liquids 111, n^o 1-3 (avril 2004) : 77–84. http://dx.doi.org/10.1016/j.molliq.2003.12.011.

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Li, Lin, Jin Zhang, Qi Chen, Kanoktip Boonkerd et Jin Kuk Kim. « Thermoreversible crosslinking of maleic anhydride grafted butyl rubber with multiple hydrogen bonding arrays ». Polymer Engineering & ; Science 54, n^o 8 (13 août 2013) : 1783–90. http://dx.doi.org/10.1002/pen.23720.

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Yan, Hua, et Xia Zhu. « Liquid crystallization of poly(styrene-co-maleic anhydride) induced by intermolecular hydrogen bonds ». Journal of Applied Polymer Science 74, n^o 1 (3 octobre 1999) : 97–105. http://dx.doi.org/10.1002/(sici)1097-4628(19991003)74:1<97 ::aid-app11>3.0.co;2-h.

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Oncescu, Tatiana, M. Contineanu et Lucia Meahcov. « Hydrogen evolution from water using CdS as photosensitizer ». International Journal of Photoenergy 1, n^o 2 (1999) : 75–78. http://dx.doi.org/10.1155/s1110662x99000148.

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Colloidal chemical approaches are increasingly utilised for the preparation and stabilization of semiconductor nanoparticles.We prepared a colloidal CdS in excess ofNa2Susing a method described in the literature and determined the particle size from its absorption spectrum by Brus equation. A diameter of about 50Å was calculated. For the stabilization of colloid we choosed from various tested polymers a 1% in weight copolymer (1/1), styrene/maleic anhydride. As redox catalyst we used colloidal Pt obtained “in situ” by irradiaton ofPtCl6K2. We established the role of each of the system partners as: CdS concentration,Na2Sexcess, Pt catalyst concentration, the irradiation time, and the system temperature. We studied the influence of each participant to the hydrogen evolution in order to optimize this system.The formation of nanosize composite particlesCd1−xZnxSshowed an increasing ofH2amount generated under irradiation, in comparison with CdS particles.The results obtained permitted us to calculate the turnover number (TO) of the system.

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Peng, Hsin Chih, Chen Feng Kuan, Chia Hsun Chen, Kun Chang Lin et Hsu Chiang Kuan. « Study on the Preparation and Properties of Multiwall Carbon Nanotube Reinforced Biodegradable Polymer Blend ». Advanced Materials Research 239-242 (mai 2011) : 145–49. http://dx.doi.org/10.4028/www.scientific.net/amr.239-242.145.

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The preparation of multi-walled carbon nanotube/polylactide (PLA)/Ecoflex® biodegradable composites is described. Three modifiers, maleic anhydride ,methyl methacrylate and vinyltrimethoxysilane , were utilized to modify multiwall carbon nanotube. The dispersion of multi-walled carbon nanotube was enhanced by covalent or hydrogen bonding between modified multi-walled carbon and biodegradable blend. The tensile strengths of pristine PLA/Ecoflex® resin and 4 wt% modified multi-walled carbon composites are 68 kgf/cm2 and 257 kgf/cm2, respectively (representing a difference of 380%). High electrical conductivity can be achieved at a low carbon nanotube loading. When 1wt% modified multi-walled carbon was added to PLA/Ecoflex® matrix, the surface resistance of the composite fell from 1.46×1016 to 7.88 × 102 Ω/Υ (by 1013 order).

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Ronka, Sylwia. « Removal of triazine-based herbicides on specific polymeric sorbent : batch studies ». Pure and Applied Chemistry 88, n^o 12 (1 décembre 2016) : 1167–77. http://dx.doi.org/10.1515/pac-2016-0906.

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AbstractThe triazine-based herbicides removal from aqueous solution on specific polymeric adsorbent was studied. Poly(divinylbenzene) modified with maleic anhydride in Diels-Alder reaction was selected for the sorption experiments because molecular structures of triazine derived herbicides exhibit complementarity to the arrangement of functional groups in the polymer. The presence of carboxyl groups in adsorbent structure resulted in specific directional interactions, such as hydrogen bonds, which can intensify adsorption ability towards triazines. In the case of both atrazine and terbuthylazine the effect is more intensive, whereas in sorption of simazine and propazine the non-specific interactions have higher importance than hydrogen bonds. Specific interactions in investigated systems are between the hydrogen atom of the amino group of triazine and the carbonyl oxygen atom of the carboxyl group of the modified poly(divinylbenzene) (O…H–N). Only in the case of terbuthylazine the creation of hydrogen bonds between hydroxyl hydrogen atom of carboxylic group and nitrogen atom containing free electron pair from triazine (O–H…N) was observed. The sorption of simazine, atrazine and propazine does not depend on pH in the acidic region, whereas in the case of terbuthylazine an increase in sorption efficiency is observed while pH decreases.

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