jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Ying Wang | Jingjing Lai | Rong Gao | Qingqiang Gou | Bingyi Li | Gang Zheng | Randi Zhang | Qiang Yue | Zhihui Song | Zifang Guo
Source: Polymers (article, 2024-06-12)
Field: Chemistry — Organic Chemistry

Recent Advances in Nickel Catalysts with Industrial Exploitability for Copolymerization of Ethylene with Polar Monomers The direct copolymerization of ethylene with polar monomers to produce functional polyolefins continues to be highly appealing due to its simple operation process and controllable product microstructure. Low-cost nickel catalysts have been extensively utilized in academia for the synthesis of polar polyethylenes. However, the development of high-temperature copolymerization catalysts suitable for industrial production conditions remains a significant challenge. Classified by the resultant copolymers, this review provides a comprehensive summary of the research progress in nickel complex catalyzed ethylene-polar monomer copolymerization at elevated temperatures in the past five years. The polymerization results of ethylene-methyl acrylate copolymers, ethylene-<i>tert</i>-butyl acrylate copolymers, ethylene-other fundamental polar monomer copolymers, and ethylene-special polar monomer copolymers are thoroughly summarized. The involved nickel catalysts include the phosphine-phenolate type, bisphosphine-monoxide type, phosphine-carbonyl type, phosphine-benzenamine type, and the phosphine-enolate type. The effective modulation of catalytic activity, molecular weight, molecular weight distribution, melting point, and polar monomer incorporation ratio by these catalysts is concluded and discussed. It reveals that the optimization of the catalyst system is mainly achieved through the methods of catalyst structure rational design, extra additive introduction, and single-site catalyst heterogenization. As a result, some outstanding catalysts are capable of producing polar polyethylenes that closely resemble commercial products. To achieve industrialization, it is essential to further emphasize the fundamental science of high-temperature copolymerization systems and the application performance of resultant polar polyethylenes. Copolymer ; Nickel ; Polar ; Ethylene ; Monomer ; Catalysis ; Materials science ; Polymer chemistry ; Chemical engineering ; Polymer ; Chemistry ; Organic chemistry ; Metallurgy ; Engineering ; Composite material Organometallic Complex Synthesis and Catalysis ; Carbon dioxide utilization in catalysis ; Asymmetric Hydrogenation and Catalysis
Authors: Yunteng Chen | Chunxian Hong | Qiang Xu | Haihong Zheng | Chao Wang | Hongshun Lu | Shuai Zhang | Mingming Du | Ganning Zeng
Source: Molecules (article, 2024-06-06)
Field: Materials Science — Materials Chemistry

Visible Light Enhancement of Biocarbon Quantum-Dot-Decorated TiO2 for Naphthalene Removal In this study, carbon-quantum-dot (CQD)-decorated TiO<sub>2</sub> was prepared using an ultrasonic doping method and applied in the photocatalytic degradation of naphthalene under sunlight irradiation. The CQDs were synthesized from a typical macroalgae via diluted sulfuric acid pretreatment and hydrothermal synthesis using an optimal design, i.e., 3 wt% and 200 °C, respectively. The CQD/TiO<sub>2</sub> composite remarkably enhanced the photocatalytic activity. The degradation of naphthalene under a visible light environment indicated that there is a synergistic mechanism between the CQDs and TiO<sub>2</sub>, in which the generation of reactive oxygen species is significantly triggered; in addition, the N that originated from the macroalgae accelerated the photocatalytic efficiency. Kinetic analysis showed that the photocatalytic behavior of the CQD/TiO<sub>2</sub> composite followed a pseudo-first-order equation. Consequently, our combined experimental approach not only provides a facile pretreatment process for bio-CQDs synthesis, but also delivers a suitable TiO<sub>2</sub> photocatalyst for the visible environment along with critical insights into the development of harmful macroalgae resources. Photocatalysis ; Naphthalene ; Hydrothermal circulation ; Materials science ; Visible spectrum ; Composite number ; Degradation (telecommunications) ; Chemical engineering ; Sulfuric acid ; Quantum dot ; Carbon fibers ; Photochemistry ; Nanotechnology ; Chemistry ; Catalysis ; Composite material ; Optoelectronics ; Organic chemistry ; Metallurgy Carbon and Quantum Dots Applications ; Advanced Photocatalysis Techniques ; Advanced Nanomaterials in Catalysis
Authors: Hassan Saeed | Qaiser Mahmood | Yanping Ma | Kainat Fatima Tahir | Geng Ren | Yizhou Wang | Wen‐Hua Sun
Source: ChemCatChem (article, 2024-12-27)
Field: Chemistry — Inorganic Chemistry

Iminopyridine‐Nickel Precatalysts for Low Molecular Weight Branched Macro‐Olefin: Dominant <i>β</i>‐Elimination Following Isomerization Abstract The chain‐walking mechanism, coupled with β ‐elimination reactions, establishes nickel complexes as a unique class of catalysts in olefin polymerization, giving access to a variety of polyethylene products from only ethylene monomer. In this study, a set of 8‐(2,6‐bis(aryl)‐3,4,5‐trifluorophenyl)imino‐5,6,7‐trihydroquinoline‐nickel bromide complexes [aryl = Ph 2 CH for Ni H , (4‐FPh) 2 CH for Ni F , (4‐ClPh) 2 CH for Ni Cl , (4‐MePh) 2 CH for Ni Me , (4‐ t BuPh) 2 CH for Ni t Bu ] was designed, prepared, and investigated for ethylene polymerization. Upon activation with MAO, these precatalysts exhibited high catalytic activity (as high as 3.1 × 10 6 g mol −1 h −1 ) and produced polyethylene with tunable chain walking (branching degree = 58–90/1000C), chain transfer (polymer M w = 0.7–2.8 kg mol −1 ), and chain termination reactions (vinylene/vinyl = 83.4%–93.6%). Electron‐donating groups at benzhydryl of aniline showed positive influence on the rate of monomer insertion and chain propagation, resulting in high catalytic activity and polymer molecular weights. Change of chain walking and chain termination rate with reaction temperature resulted in polyethylene with varied physical states from sticky wax to thick oil. Most importantly, β ‐elimination is the predominant route for chain termination reaction and produces polyethylene with a high ratio of internal double bonds (─CH═CH─/CH 2 ═CH─ up to 93.6%). These macromers are important for post‐modification processes. Isomerization ; Olefin fiber ; Nickel ; Chemistry ; Organic chemistry ; Catalysis Asymmetric Hydrogenation and Catalysis ; Organometallic Complex Synthesis and Catalysis ; Nanomaterials for catalytic reactions
Authors: Joost J. B. van der Tol | Shahzad Hafeez | Andy P. G. Bänziger | Hao Su | Johan P. A. Heuts | E. W. Meijer | Ghislaine Vantomme
Source: Advanced Materials (article, 2024-10-17)
Field: Materials Science — Polymers and Plastics

Supramolecular Polymer Additives as Repairable Reinforcements for Dynamic Covalent Networks Employing rigid (in)organic materials as reinforcement for dynamic covalent networks (DCNs) is an effective approach to develop high-performance materials. Yet, recycling of these materials after failure often necessitates inefficient chemical reprocessing or inevitably alters their performance due to unrepairable inert components. Here, a non-covalent reinforcement strategy is presented by introducing a supramolecular additive to a DCN that can reversibly depolymerize and reform on demand, therefore acting as an adaptive and repairable reinforcement. The strong hydrogen-bonding interactions in the supramolecular polymer of triazine-1,3,5-tribenzenecarboxamide (S-T) strengthen the DCN at room temperature, while its non-covalent nature allows for easy one-pot reprocessing at high temperatures. Depending on wether S-T is covalently bond to the DCN or not, it can play either the role of compatibilizer or filler, providing a synthetic tool to control the relaxation dynamics, reprocessability and mechanical properties. Moreover, the S-T reinforcement can be chemically recovered with high yield and purity, showcasing the recyclability of the composite. This conceptually novel supramolecular reinforcement strategy with temperature-controlled dynamics highlights the potential of supramolecular polymer additives to replace conventional unrepairable reinforcements. Supramolecular chemistry ; Covalent bond ; Materials science ; Supramolecular polymers ; Reinforcement ; Polymer ; Hydrogen bond ; Inert ; Nanotechnology ; Polymer chemistry ; Composite material ; Molecule ; Chemistry ; Organic chemistry Polymer composites and self-healing ; Covalent Organic Framework Applications ; Conducting polymers and applications
Authors: Daniel Bůžek | Jan Hynek | Matouš Kloda | Veronika Zlámalová | Petr Bezdička | Slavomír Adamec | Kamil Lang | Jan Demel
Source: Inorganic Chemistry Frontiers (article, 2024-01-01)
Field: Chemistry — Inorganic Chemistry

Zirconium-based metal–organic frameworks: the relation between linker connectivity, structure stability, and catalytic activity towards organophosphates The stability of MOFs in aqueous environments is influenced by the linker topicity rather than by the connectivity. Only MIP-200 survives the alkaline environment. Linker ; Zirconium ; Catalysis ; Aqueous solution ; Metal-organic framework ; Metal ; Chemistry ; Materials science ; Chemical engineering ; Inorganic chemistry ; Organic chemistry ; Computer science Metal-Organic Frameworks: Synthesis and Applications ; Molecular Sensors and Ion Detection ; Crystallography and molecular interactions
Authors: Josmi John | K. S. Archana | Ashley Mariam Thomas | Rose Leena Thomas | Jeena Thomas | Vinoy Thomas | N.V. Unnikrishnan
Source: Sustainable Chemical Engineering (article, 2024-01-15)
Field: Chemistry — Organic Chemistry

Nitrocellulose Unveiled: A Brief Exploration of Recent Research Progress Nitrocellulose is a versatile material with a wide range of applications across various industries. This review article provides an overview of the present state of nitrocellulose technology and explores its future perspectives. It looks at how nitrocellulose is being used in fields like the military, explosives, coatings, inks, and medical equipment. Additionally, it investigates the demand for alternative cellulose raw materials in the manufacture of nitrocellulose while taking sustainability, resource accessibility, and cost-effectiveness into account. The paper also explores the creation of novel nitrating mixtures for the production of cellulose nitrate, concentrating on process optimization, environmental concerns, and safety. The study also discusses new developments and ongoing nitrocellulose research. To emphasize the significance of innovation and sustainable practices in determining its future, the article finally finishes by detailing the future possibilities and developing trends in nitrocellulose applications. Nitrocellulose ; Nanotechnology ; Sustainability ; Engineering ; Resource (disambiguation) ; Engineering ethics ; Biochemical engineering ; Manufacturing engineering ; Computer science ; Materials science ; Chemistry Nanomaterials for catalytic reactions
Authors: Mehmet Arslan | Aysun Degirmenci | Rana Sanyal | Amitav Sanyal
Source: Polymer Chemistry (article, 2024-01-01)
Field: Chemistry — Organic Chemistry

Tetrazine-based inverse-electron-demand Diels–Alder reaction: a powerful tool for fabrication and functionalization of polymeric materials The IEDDA click reaction plays an important role in the fabrication and functionalization of polymeric materials. Tetrazine ; Surface modification ; Inverse ; Alder ; Diels–Alder reaction ; Fabrication ; Chemistry ; On demand ; Nanotechnology ; Combinatorial chemistry ; Computer science ; Materials science ; Organic chemistry ; Mathematics ; Botany ; Biology ; Catalysis Click Chemistry and Applications ; Chemical Synthesis and Analysis ; Molecular Junctions and Nanostructures
Authors: Zhen Yu | Qiong Li | Yanlin Liu | Shu Tian | Wanding Chen | Yingying Han | Zhaobin Tang | Junping Zhang
Source: Advanced Science (article, 2024-06-13)
Field: Materials Science — Polymers and Plastics

Malleable, Ultrastrong Antibacterial Thermosets Enabled by Guanidine Urea Structure Dynamic covalent polymers (DCPs) that strike a balance between high performance and rapid reconfiguration have been a challenging task. For this purpose, a solution is proposed in the form of a new dynamic covalent supramolecular motif-guanidine urea structure (GUAs). GUAs contain complex and diverse chemical structures as well as unique bonding characteristics, allowing guanidine urea supramolecular polymers to demonstrate advanced physical properties. Noncovalent interaction aggregates (NIAs) have been confirmed to form in GUA-DCPs through multistage H-bonding and π-π stacking, resulting in an extremely high Young's modulus of 14 GPa, suggesting remarkable mechanical strength. Additionally, guanamine urea linkages in GUAs, a new type of dynamic covalent bond, provide resins with excellent malleability and reprocessability. Guanamine urea metathesis is validated using small molecule model compounds, and the temperature dependent infrared and rheological behavior of GUA-DCPs following the dissociative exchange mechanism. Moreover, the inherent photodynamic antibacterial properties are extensively verified by antibacterial experiments. Even after undergoing three reprocessing cycles, the antibacterial rate of GUA-DCPs remains above 99% after 24 h, highlighting their long-lasting antibacterial effectiveness. GUA-DCPs with dynamic nature, tuneable composition, and unique combination of properties make them promising candidates for various technological advancements. Covalent bond ; Supramolecular chemistry ; Non-covalent interactions ; Guanidine ; Polymer ; Urea ; Materials science ; Chemical engineering ; Thermosetting polymer ; Supramolecular polymers ; Chemistry ; Nanotechnology ; Polymer chemistry ; Organic chemistry ; Molecule ; Hydrogen bond Polymer composites and self-healing ; Advanced Polymer Synthesis and Characterization ; Photochromic and Fluorescence Chemistry
Authors: Abhishek Rajbanshi | Eleanor Hilton | Cécile A. Dreiss | Darragh Murnane | Michael T. Cook
Source: Macromolecular Rapid Communications (article, 2024-02-24)
Field: Materials Science — Materials Chemistry

Stimuli‐Responsive Polymers for Engineered Emulsions Emulsions are complex. Dispersing two immiscible phases, thus expanding an interface, requires effort to achieve and the resultant dispersion is thermodynamically unstable, driving the system toward coalescence. Furthermore, physical instabilities, including creaming, arise due to presence of dispersed droplets of different densities to a continuous phase. Emulsions allow the formulation of oils, can act as vehicles to solubilize both hydrophilic and lipophilic molecules, and can be tailored to desirable rheological profiles, including "gel-like" behavior and shear thinning. The usefulness of emulsions can be further expanded by imparting stimuli-responsive or "smart" behaviors by inclusion of a stimuli-responsive emulsifier, polymer or surfactant. This enables manipulation like gelation, breaking, or aggregation, by external triggers such as pH, temperature, or salt concentration changes. This platform generates functional materials for pharmaceuticals, cosmetics, oil recovery, and colloid engineering, combining both smart behaviors and intrinsic benefit of emulsions. However, with increased functionality comes greater complexity. This review focuses on the use of stimuli-responsive polymers for the generation of smart emulsions, motivated by the great adaptability of polymers for this application and their efficacy as steric stabilizers. Stimuli-responsive emulsions are described according to the trigger used to provide the reader with an overview of progress in this field. Rheology ; Polymer ; Materials science ; Smart polymer ; Creaming ; Emulsion ; Pulmonary surfactant ; Viscoelasticity ; Chemical engineering ; Colloid ; Coalescence (physics) ; Smart material ; Nanotechnology ; Shear thinning ; Enhanced oil recovery ; Oil droplet ; Composite material Pickering emulsions and particle stabilization ; Advanced Polymer Synthesis and Characterization ; Surfactants and Colloidal Systems
Authors: Song Wang | Yangyang Han | Vaishnavi Amarr Reddy | Mervin Chun‐Yi Ang | Gabriel Sánchez-Velázquez | Jolly M. Saju | Yunteng Cao | Duc Thinh Khong | J. Kumar | Raju Cheerlavancha | Suh In Loh | Gajendra Singh | Daisuke Urano | Rajani Sarojam | Benedetto Marelli | Michael S. Strano
Source: Nature Communications (article, 2024-10-28)
Field: Materials Science — Materials Chemistry

Chromatic covalent organic frameworks enabling in-vivo chemical tomography Covalent organic frameworks designed as chromatic sensors offer opportunities to probe biological interfaces, particularly when combined with biocompatible matrices. Particularly compelling is the prospect of chemical tomography - or the 3D spatial mapping of chemical detail within the complex environment of living systems. Herein, we demonstrate a chromic Covalent Organic Framework (COF) integrated within silk fibroin (SF) microneedles that probe plant vasculature, sense the alkalization of vascular fluid as a biomarker for drought stress, and provide a 3D in-vivo mapping of chemical gradients using smartphone technology. A series of Schiff base COFs with tunable pKa ranging from 5.6 to 7.6 enable conical, optically transparent SF microneedles with COF coatings of 120 to 950 nm to probe vascular fluid and the surrounding tissues of tobacco and tomato plants. The conical design allows for 3D mapping of the chemical environment (such as pH) at standoff distances from the plant, enabling in-vivo chemical tomography. Chromatic COF sensors of this type will enable multidimensional chemical mapping of previously inaccessible and complex environments. Chemical imaging ; Materials science ; Covalent bond ; Biocompatible material ; Nanotechnology ; Chromatic scale ; In vivo ; Tomography ; Fibroin ; Biomedical engineering ; Chemistry ; Computer science ; SILK ; Optics ; Hyperspectral imaging ; Organic chemistry ; Composite material Covalent Organic Framework Applications ; Luminescence and Fluorescent Materials ; Caching and Content Delivery
Authors: Ana Dias | Edgar Felizardo | N. Bundaleska | M. V. Abrashev | Jivko Kissovski | Ana M. Ferraria | A.M. Botelho do Rego | Thomas Strunskus | P.A. Carvalho | A. Almeida | Janez Zavašnik | Eva Kovačević | Johannes Berndt | Nenad Bundaleski | Mohammed-Ramzi Ammar | Orlando M.N.D. Teodoro | Uroš Cvelbar | Luís L. Alves | B. Gonçalves | E. Tatarova
Source: Applied Materials Today (article, 2024-01-20)
Field: Materials Science — Materials Chemistry

Plasma-enabled multifunctional platform for gram-scale production of graphene and derivatives Taking advantage of the high-energy-density microwave plasma environment as a unique 3D space for the self-assembly of free-standing nanostructures, a novel multifunctional platform for the continuous production of graphene and derivatives at the gram scale was developed. The platform is supported by a prototype plasma machine capable of performing a wide variety of industrially applicable processes within a single assembly environment. Free-standing graphene and nitrogen doped graphene, i.e., N-graphene nanosheets, and hybrid nanocomposites are assembled in a one-step process in seconds under atmospheric pressure conditions without the need of post-treatment. A single custom-designed machine enables the synthesis of an extensive array of hybrid nanomaterials featuring metal nanoparticles anchored in graphene. The method enables the conversion of a wide range of low-cost feedstock (e.g., ethanol, acetonitrile, etc.) into graphene and derivatives at a rate up to 30 mg/min. The resulting N-graphene sheets exhibit high quality, as evidenced by the highest reported presence of single atomic layers (45%), high ratio of 2D/G peak intensities in Raman spectra and N/O atomic ratio greater than one. The use of the obtained N-graphene in low secondary electron emission applications and in inkjet printing are explored. The presented plasma machine embodies significant potential to increase the effectiveness of plasma-driven process regarding productivity, costs and turnaround time. Graphene ; Materials science ; Nanotechnology ; Nanomaterials ; Raman spectroscopy Graphene research and applications ; Graphene and Nanomaterials Applications ; Nanomaterials for catalytic reactions
Authors: Jixing Che | Siqiang Fang | Zanjiao Liu | Jiajia He | Jia‐Yan Zheng | Fan Wang | Tianli Wang
Source: Chinese Journal of Chemistry (article, 2024-04-29)
Field: Chemistry — Organic Chemistry

Access to Enantioenriched Allylic Alcohols via <scp>Peptide‐Mimic</scp> Phosphonium <scp>Salt‐Catalyzed</scp> Asymmetric Aerobic Hydroxylation Comprehensive Summary The development of catalytic asymmetric methods that enable access to value‐added functionalities or structures, exemplified by allylic alcohols, is a highly interesting yet challenging topic from both academic and industrial perspectives. However, before recent advances in chemical catalysis, there were scarce protocols toward constructing enantioenriched tertiary allylic alcohol scaffolds. In this context, peptide‐mimic phosphonium salts were found to be highly efficient in catalytic asymmetric α‐hydroxylation of α,β‐unsaturated and/or β,ϒ‐unsaturated compounds with satisfactory regio‐ and stereochemical outcomes (up to 97% yield and 95% ee). This methodology tolerates a broad array of substrates and thus provides an expeditious and unified platform for the assembly of enantioenriched tertiary allylic alcohols by avoiding the use of additional reductants and expensive metal catalysts. Furthermore, the power of this protocol is enlarged by simple conditions and the use of air as a source of hydroxyl functionality. Chemistry ; Allylic rearrangement ; Catalysis ; Hydroxylation ; Enantioselective synthesis ; Combinatorial chemistry ; Context (archaeology) ; Phosphonium ; Organic chemistry Synthesis and Catalytic Reactions ; Chemical Synthesis and Analysis ; Asymmetric Synthesis and Catalysis
Authors: Benjamin Mourot | Denis Jacquemin | Olivier Siri | Simon Pascal
Source: The Chemical Record (review, 2024-11-11)
Field: Materials Science — Materials Chemistry

Coupled Polymethine Dyes: Six Decades of Discoveries This review provides a comprehensive examination of the applications of the seminal coupling principle introduced by Siegfried Dähne and Dieter Leupold in 1966. Their heuristic and groundbreaking work proposed that combining multiple polymethine subunits within a single chromophore enables orbital coupling, consequently narrowing the HOMO-LUMO gap, and yielding redshifted optical properties. These outcomes are particularly valuable for developing organic dyes tailored for visible-to-near-infrared applications. Despite their potential, coupled polymethines remain relatively underexplored, with most reported instances being serendipitous discoveries over the last six decades. In light of this, our review compiles and discusses the reported coupled polymethine structures, covering synthetic, spectroscopic, theoretical and applicative aspects, offering insights into the structure-property relationships of this unique class of dyes and perspectives for their future applications. Chromophore ; Nanotechnology ; Coupling (piping) ; HOMO/LUMO ; Materials science ; Computer science ; Chemistry ; Photochemistry ; Molecule ; Organic chemistry Luminescence and Fluorescent Materials ; Photochromic and Fluorescence Chemistry ; Photochemistry and Electron Transfer Studies