RSC Mechanochemistry最新文献

{"title":"Thermodynamic limits of the depolymerization of poly(olefin)s using mechanochemistry.","authors":"Yuchen Chang, Van Son Nguyen, Adrian H Hergesell, Claire L Seitzinger, Jan Meisner, Ina Vollmer, F Joseph Schork, Carsten Sievers","doi":"10.1039/d4mr00079j","DOIUrl":"https://doi.org/10.1039/d4mr00079j","url":null,"abstract":"<p><p>Mechanochemistry is a promising approach for chemical recycling of commodity plastics, and in some cases depolymerization to the monomer(s) has been reported. However, while poly(olefin)s comprise the largest share of global commodity plastics, mechanochemical depolymerization of these polymers in standard laboratory-scale ball mill reactors suffers from slow rates. In this work, the observed reactivities of poly(styrene), poly(ethylene) and poly(propylene) are rationalized on the basis of thermodynamic limitations of their depolymerization by depropagation of free radical intermediates. In addition, subsequent phase partitioning equilibria for the removal of monomers from the reactor <i>via</i> a purge gas stream are discussed for these polymers. For poly(styrene), a typical vibratory ball mill supplies just enough energy for its depolymerization to be driven by either thermal hotspots or adiabatic compression of the impact site, but the same energy supply is far from sufficient for poly(propylene) and poly(ethylene). Meanwhile, removal of styrene from the reactor is thermodynamically hindered by its lower volatility, but this is not an issue for either propylene or ethylene. The implications of these thermodynamic limitations for mechanochemical reactor design and potential for mechanocatalytic processes are highlighted.</p>","PeriodicalId":101140,"journal":{"name":"RSC Mechanochemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11388944/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142305505","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling mechanochemistry: pressure dependence of Diels–Alder cycloaddition reaction kinetics†","authors":"Nicholas Hopper, François Sidoroff, Juliette Cayer-Barrioz, Denis Mazuyer, Bo Chen and Wilfred T. Tysoe","doi":"10.1039/D4MR00063C","DOIUrl":"https://doi.org/10.1039/D4MR00063C","url":null,"abstract":"<p >We analyze the effect of pressure on the Diels–Alder (D–A) dimerization reactions using Evans–Polanyi (E–P) theory, a thermodynamic analysis of the way in which a perturbation, in this case a hydrostatic pressure, modifies a reaction rate. Because it is a thermodynamic analysis, the results depend only on the volumes of the initial- and transition-state structures and not on the pathways between them. The volumes are calculated by enclosing the initial- and transition-state structures in a van der Waals' cocoon. Pressure is exerted by multiplying the van der Waals' radii by some factor without allowing the initial- and transition-state structures to relax. The influence of the surrounding solvent is included by using the extreme-pressure, polarizable-continuum method (XP-PCM). The approach is illustrated in detail using cyclopentadiene dimerization for which the rates have been independently measured by two groups. The analysis provides results that are in good agreement with those found experimentally for measurements made up to ∼0.3 GPa. The activation volumes of other D–A reactions are calculated in the same way and lead to good agreement for non-polar reactants, but less good agreement for polar ones. The pressure can also distort the initial- and transition-state structures, which can be calculated from the initial- and transition-state Hessians. A pressure-dependent distortion requires knowing the area over which the hydrostatic pressure acts. This is obtained using the Stearn–Eyring postulate that the activation volume is the product of an activation length and the area over which the stress acts. The activation length is obtained from quantum calculations of the difference in the distances between the diene and dienophile in the initial- and transition states. This provides only minor corrections to the results for routinely accessible hydrostatic pressures.</p>","PeriodicalId":101140,"journal":{"name":"RSC Mechanochemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/mr/d4mr00063c?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142165146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanochemical extraction of edible proteins from moor grass†","authors":"Olusegun Abayomi Olalere, Fatma Guler, Christopher J. Chuck, Hannah S. Leese and Bernardo Castro-Dominguez","doi":"10.1039/D4MR00016A","DOIUrl":"https://doi.org/10.1039/D4MR00016A","url":null,"abstract":"<p >Extracting edible nutrient-rich food fractions from unconventional sources, such as grass, could play a pivotal role in ensuring food security, bolstering economic prosperity, combating climate change, and enhancing overall quality of life. Current extraction techniques rely heavily on harsh chemicals, which not only degrade nutrients but can also substantially add to the cost of the process and make downstream separation challenging. In this study, we harnessed a mechanochemical process, liquid-assisted grinding (LAG) with and without Na<small>₂</small>CO<small>₃</small>, termed sodium carbonate assisted grinding (SAG), to extract the protein fraction from moor grass. These techniques were compared to the conventional alkaline extraction (AE) method. Unlike alkaline extraction, which solubilized over 70% of the material, the mechanochemical approach using Na<small>₂</small>CO<small>₃</small> solubilized only 55% of the grass while still extracting the vast majority of the protein in the original grass feedstock. The protein fractions obtained from the SAG process had a similar amino acid profile to the core feedstock but also contained distinct characteristics over the other methods of extraction. FT-IR analysis, for example, identified the presence of an amide III band in the protein fractions obtained from the SAG process, indicating unique structural features that contribute to improved dispersibility, gelation properties, and water-in-water stability. Furthermore, the extracted moor grass protein contained a higher proportion of glutamic acid in comparison to other amino acids in the protein, which indicates a savoury umami (meaty) characteristic to the protein fraction. The protein extracted <em>via</em> SAG also exhibited good heat stability (139–214 °C), rendering them potentially suitable for baking applications. Additionally, coupling Na<small>₂</small>CO<small>₃</small> with liquid assisted grinding not only removed the need for organic solvents and conventional heating but also reduced solvent consumption by 83%, compared with the typical alkaline extraction, thus simplifying the downstream processes necessary to produce food fractions. This study demonstrates the potential significance of mechanochemical extraction processes in unlocking nutrients from unconventional resources like grass, to produce the next generation of sustainable food ingredients.</p>","PeriodicalId":101140,"journal":{"name":"RSC Mechanochemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/mr/d4mr00016a?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142165143","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Advancing sustainable practices in Li-ion battery cathode material recycling: mechanochemical optimisation for magnetic cobalt recovery†","authors":"Joshua Vauloup, Cécile Bouilhac, Nicolas Coppey, Patrick Lacroix-Desmazes, Bernard Fraisse, Lorenzo Stievano, Laure Monconduit and Moulay Tahar Sougrati","doi":"10.1039/D4MR00018H","DOIUrl":"https://doi.org/10.1039/D4MR00018H","url":null,"abstract":"<p >Lithium-ion batteries (LIBs) stand as the dominant power source for electric vehicles owing to their mature technology and exceptional performance. Consequently, metallic components of LIB cathode materials (Ni, Co, Li, and Mn) are assuming strategic significance. The imperative recycling of these metals has necessitated the development of novel technologies that can curtail secondary pollution arising from prevailing hydrometallurgical procedures, including issues such as wastewater generation and excessive energy and chemical consumption. In this study, we present an optimised mechanochemical process tailored for the magnetic recovery of cobalt from LiCoO<small>₂</small>, which is a crucial component of LIBs. Our methodology involves the initial reduction of cobalt, facilitated by aluminium, followed by a selective extraction process that leverages the magnetic properties of the obtained species. A systematic exploration of milling parameters was undertaken to comprehensively understand their influence on chemical reactions and to improve reduction efficiency. This research represents a significant stride towards fostering sustainable practices in the realm of LIB cathode material recycling, addressing critical concerns related to resource management and environmental impact.</p>","PeriodicalId":101140,"journal":{"name":"RSC Mechanochemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/mr/d4mr00018h?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142165145","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Polymer vessels in mechanochemical syntheses: assessing material performance†","authors":"Marisol Fabienne Rappen, Lars Beissel, Jonathan Geisler, Simeon Theodor Tietmeyer, Sven Grätz and Lars Borchardt","doi":"10.1039/D4MR00059E","DOIUrl":"https://doi.org/10.1039/D4MR00059E","url":null,"abstract":"<p >This work provides an overview of sixteen different polymers potentially applicable as vessel materials in mechanochemical reactions, facilitating the selection of the optimal material tailored to each system individually. The investigation focused on the chemical resistances, especially under simultaneous mechanical stress, and the long-term stability of the utilized polymers. To assess these aspects, two reference reactions were employed: the direct mechanocatalytic Suzuki coupling of iodobenzene and phenylboronic acid, and the acid-catalysed acetalization reaction of ethylene glycol and 3-nitrobenzaldehyde. The palladium abrasion of the precious milling ball material used in the Suzuki reaction was examined through ICP-OES measurements for the polymers studied. Additionally, the temperature resistance of the polymers was discussed, along with their aptitude for <em>in situ</em> monitoring.</p>","PeriodicalId":101140,"journal":{"name":"RSC Mechanochemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/mr/d4mr00059e?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142165144","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Total mechano-synthesis of 2-cyclopropyl-4-(4-fluorophenyl)quinoline-3-acrylaldehyde—a pivotal intermediate of pitavastatin†","authors":"Jingbo Yu, Yanhua Zhang, Zehao Zheng and Weike Su","doi":"10.1039/D4MR00036F","DOIUrl":"https://doi.org/10.1039/D4MR00036F","url":null,"abstract":"<p >Pitavastatin (PTV), a potent cholesterol-lowering agent, holds considerable commercial appeal, driving chemists to fervently pursue its efficient and sustainable synthesis. Despite prolonged efforts over several decades, the quest for a simplified, more efficacious, and environmentally conscious manufacturing process for PTV remains a significant challenge. Our study introduces a three-step total mechano-synthesis, commencing with readily available 4-bromoquinoline, to produce the key intermediate (2-cyclopropyl-4-(4-fluorophenyl)quinoline-3-acrylaldehyde) of PTV. This methodology incorporates an extrusive Suzuki–Miyaura coupling, mechanochemical Minisci C–H alkylation, and extrusive oxidation Heck coupling, each thoroughly presented to display their scalability. Notably, we emphasize the extensive exploration of substrate versatility in Minisci reactions to access cyclopropane-bearing pharmaceutical compounds and natural products. This total mechano-synthesis route distinguishes itself through eco-friendly reaction conditions, exceptional stepwise efficiency, intuitive operability, and pronounced potential for large-scale implementation, paving the way for PTV's streamlined and sustainable manufacture.</p>","PeriodicalId":101140,"journal":{"name":"RSC Mechanochemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/mr/d4mr00036f?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142165110","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Elucidating tribochemical reaction mechanisms: insights into tribofilm formation from hydrocarbon adsorbates coupled with tribochemical substrate wear†","authors":"Yu-Sheng Li, Fakhrul H. Bhuiyan, Jongcheol Lee, Ashlie Martini and Seong H. Kim","doi":"10.1039/D3MR00036B","DOIUrl":"https://doi.org/10.1039/D3MR00036B","url":null,"abstract":"<p >Tribochemical reactions, chemical processes that occur by frictional shear at sliding interfaces, lead to tribofilm formation or substrate wear that directly affect the efficiency of machinery. Here, we report tribofilm growth through tribopolymerization and tribochemical wear of a silica surface due to reactions with organic precursors methylcyclopentane, cyclohexane, cyclohexene, and α-pinene. The activation volume determined from the stress dependence of reaction yield is correlated to the chemical reactivity of the precursor molecules. The molecules with higher tribochemical reactivity exhibited smaller activation volume, implying that less mechanical energy was required to initiate tribochemical reactions. Nudged elastic band calculations for the hypothetical pathways for the observed tribochemical reactions suggested that the smaller activation volume could be related to smaller thermal activation energy at the rate-limiting step. The tribofilm formation yield was found to increase with load whereas the load dependence of tribochemical wear was negligible. The environment dependence of the sliding processes was also analyzed. Results showed that, compared to a dry N<small>₂</small> environment, the tribopolymerization reaction yield increased in dry air but decreased in N<small>₂</small> with 40% relative humidity, while the wear rate remained unchanged. This finding suggested that during sliding, the reactive sites exposed at the worn surface could be re-oxidized by even trace amounts of oxygen or water vapor in the environment. This analysis of tribofilm yield and substrate wear in various environments showed that ambient gas can change the tribochemical reactivities of the reactant, which leads to different load dependencies of tribopolymerization and tribochemical wear.</p>","PeriodicalId":101140,"journal":{"name":"RSC Mechanochemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/mr/d3mr00036b?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142165141","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Facile mechanochemical synthesis of hypervalent tin(iv)-fused azo/azomethine compounds showing solid-state emission†","authors":"Masayuki Gon, Taichi Kato, Kazuya Tanimura, Chiaki Hotta and Kazuo Tanaka","doi":"10.1039/D4MR00048J","DOIUrl":"https://doi.org/10.1039/D4MR00048J","url":null,"abstract":"<p >Mechanochemical synthesis involves carrying out chemical reactions without solvents and has attracted much attention as green chemistry. Herein, we demonstrate solvent- and catalyst-free mechanochemical synthesis of hypervalent tin(<small>IV</small>) compounds with azo/azomethine tridentate ligands and organotin(<small>IV</small>) oxide by manual grinding in an agate mortar. FT-IR spectra indicate that 41–82% of the ligands can be converted to hypervalent tin compounds depending on the reaction conditions. The resulting products exhibit solid-state emission in the yellow to deep-red region without purification.</p>","PeriodicalId":101140,"journal":{"name":"RSC Mechanochemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/mr/d4mr00048j?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142165140","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanochemical transformation of tetraaryl[3]cumulenes to benzofulvenes via electrophilic iodocyclization†","authors":"Fumitoshi Yagishita, Shoma Mukai, Sota Abe, Shoko Ueta, Yasushi Yoshida, Yukihiro Arakawa, Keiji Minagawa and Yasushi Imada","doi":"10.1039/D4MR00022F","DOIUrl":"https://doi.org/10.1039/D4MR00022F","url":null,"abstract":"<p >We demonstrate solvent-free mechanochemical iodocyclization of tetraaryl[3]cumulenes using <em>N</em>-iodosuccinimides as the first example of the molecular transformation of cumulenes based on mechanochemistry. This mechanochemical reaction provides the corresponding benzofulvenes in good yields, overcoming the limitation of conventional methods using organic solvents.</p>","PeriodicalId":101140,"journal":{"name":"RSC Mechanochemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/mr/d4mr00022f?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142165139","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Atomistic simulations of mechanically activated reactions for oxygen release from polymers†","authors":"José Cobeña-Reyes, Fakhrul H. Bhuiyan and Ashlie Martini","doi":"10.1039/D4MR00004H","DOIUrl":"https://doi.org/10.1039/D4MR00004H","url":null,"abstract":"<p >Singlet oxygen molecules are useful in several therapeutic applications involving photo-activated release of oxygen from carrier molecules toward targeted cells. However, the drawbacks of existing photo-activated methods encourage the development of alternatives, particularly polymer mechanophores that act as oxygen carriers. Here, we present a reactive molecular dynamics simulation-based study of an endoperoxide-based polymer for which oxygen release can be activated either thermally or mechanochemically. Simulations of the polymers heated are compared to simulations of the polymers subject to compression and shear at room temperature. Results show that oxygen release is preceded by deformation of the anthracene ring in both thermal and mechanochemical reactions. However, in the mechanically activated reaction, this deformation is imposed directly by chemical bonding between the oxygen and atoms in the shearing surfaces, eliminating the need for high temperature to initiate the oxygen release. These results could be useful in the development of alternative therapeutic protocols that do not rely on photo-activated reactions.</p>","PeriodicalId":101140,"journal":{"name":"RSC Mechanochemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/mr/d4mr00004h?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142165109","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}