Faraday Discussions最新文献

{"title":"Analysing π-π-stacking interactions in lignin nanoparticles from molecular simulations - insights and lessons learned.","authors":"Klara Hackenstrass, Nil Tabudlong Jonasson, Marie Hartwig-Nair, Tomas Rosén, Sara Florisson, Malin Wohlert","doi":"10.1039/d5fd00052a","DOIUrl":"https://doi.org/10.1039/d5fd00052a","url":null,"abstract":"<p><p>A special molecular association is π-π-stacking, driven by weak interactions within aromatic compounds. The π-π-stacking interactions can occur in either a sandwich-like or T-shaped manner. In this study, a method to recognise π-π-stacking from classical molecular dynamics trajectories is developed. By applying three criteria, the method is tested for simple lignin dimer, tetramer and octamer systems, with all G units and β-O4' linkages. The criteria are geometric and based on distance between ring centroids, the angle between the planes of the two rings and the lateral displacement of the rings. In addition, a wide-angle X-ray scattering (WAXS) profile was calculated from a tetramer system, in agreement with previous experimental results. However, when the WAXS peak assigned to sandwich-shaped stacking was analysed in-depth, it was found to mainly be caused by other intramolecular structural motifs involving <i>e.g.</i> the α-carbon and ring carbons, rather than π-π-stacking. This finding is important for future analyses of WAXS profiles originating from lignin-based materials and shows the strength of combining X-ray scattering methods with molecular modelling.</p>","PeriodicalId":76,"journal":{"name":"Faraday Discussions","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2025-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145111555","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Efficient and controlled ring-opening copolymerization of cyclohexene oxide with cyclic anhydrides catalyzed by proline-based chiral alkyl Al(III) compounds.","authors":"Ranay Kumar Ray, P K Sudhadevi Antharjanam, Debashis Chakraborty","doi":"10.1039/d5fd00048c","DOIUrl":"https://doi.org/10.1039/d5fd00048c","url":null,"abstract":"<p><p>A set of new chiral monomeric (<i>S</i>)- and (<i>R</i>)-isomers of Al(III) compounds were synthesized using a proline-based ligand moiety. The reaction of AlMe₃ with one equivalent of pro-ligands (1a-d) in dry toluene yielded the corresponding dimethyl Al(III) compounds (2a-d) in high yields. The molecular structures of compounds 2a, 2c and 2d were confirmed using single-crystal X-ray diffraction analysis. These compounds exhibited a distorted tetrahedral geometry at the Al(III) center. These compounds were tested as catalysts for the ring-opening copolymerization (ROCOP) of cyclohexane oxide (CHO) with cyclic anhydrides to produce copolyesters with tetraphenyphosphonium chloride (TPPCl) as a cocatalyst. The (<i>S</i>)-isomer was found to be more reactive than the (<i>R</i>)-isomer towards the ROCOP. Alternating polyesters were obtained from the ROCOP of cyclohexene oxide (CHO) with phthalic anhydride (PA) and CHO with succinic anhydride (SA), producing copolyesters with moderate to high <i>M</i>_n (9589 g mol^-1) and with narrow dispersity (<i>Đ</i>) (1.23). The (<i>S</i>)-isomer substituted with fluorine atoms at the phenyl ring was most active for the polymerization reactions. The kinetics studies of ROCOP performed using 2a (<i>S</i>-isomer) as catalyst showed higher rate than 2d (<i>R</i>-isomer). 2a produced an isotactic-enriched semicrystalline polyester, whereas 2d formed an atactic amorphous polyester. The DSC traces revealed that the glass transition temperature (<i>T</i>_g) increases with increasing molecular weight (<i>M</i>_n) of these polyesters.</p>","PeriodicalId":76,"journal":{"name":"Faraday Discussions","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2025-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145111557","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tuning ester derivatives of organosolv <i>vs.</i> technical lignin for improved thermoplastic materials.","authors":"Mahendra Kothottil Mohan, T Tran Ho, Carmen Köster, Oliver Järvik, Maria Kulp, Yevgen Karpichev","doi":"10.1039/d5fd00068h","DOIUrl":"https://doi.org/10.1039/d5fd00068h","url":null,"abstract":"<p><p>In this study, lignin from two different sources - organosolv pine and hydrolysis birch - were chemically modified through esterification of hydroxyl groups using octanoyl (C8), lauroyl (C12), and palmitoyl (C16) chlorides, as well as through chloromethylation followed by esterification with tetradecanoic acid (C14) and benzoic acid. Modification of lignin was confirmed by FTIR and NMR spectroscopy. The esterified lignin samples were loaded into polylactic acid (PLA) at loadings of 10%, 20%, and 30% using a solvent casting method. Thermal and mechanical properties of PLA/lignin composites revealed that esterification significantly affected the polymer matrix properties. PLA could sustain as much as 30% lignin ester loading without affecting the film integrity. Among the variations, hydrolysis lignin ester (HLE) and benzoic acid ester (BAEP) enhanced the heat stability of PLA, while esterification with palmitoyl chloride (OHLE_C16) increased its elasticity through plasticization.</p>","PeriodicalId":76,"journal":{"name":"Faraday Discussions","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2025-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145111605","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chemical recycling of polylactide by microwave-assisted processes.","authors":"Federica Santulli, Mauro Pio Ferrandino, Costantino Cioffi, Maria Rosaria Acocella, Marina Lamberti, Mina Mazzeo","doi":"10.1039/d5fd00078e","DOIUrl":"https://doi.org/10.1039/d5fd00078e","url":null,"abstract":"<p><p>The chemical recycling of post-consumer polylactic acid by microwave-assisted alcoholysis promoted by a phenoxy-imine pyridine zinc is investigated. Different alcohols and diols are used to achieve, in all cases, outstanding activity and selectivity toward the targeted products. Thanks to the robustness of the catalyst the reactions can be performed in the air, with technical grade reagents and without the use of additional solvents, thus ensuring the full sustainability of the procedure.</p>","PeriodicalId":76,"journal":{"name":"Faraday Discussions","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2025-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145111539","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An old tool to obtain new polymers from renewable resources: [OSSO]-type titanium-catalysed ethylene and myrcene copolymers.","authors":"Fatemeh Niknam, Antonio Buonerba, David Hermann Lamparelli, Carmine Capacchione","doi":"10.1039/d5fd00046g","DOIUrl":"https://doi.org/10.1039/d5fd00046g","url":null,"abstract":"<p><p>The copolymerization of β-myrcene (M) with ethylene (E) and isoprene (I) was successfully promoted by a dichloro{1,4-dithiabutanediyl-2,2'-bis(4,6-di-alkylphenoxy)}titanium complex (1) activated by methylaluminoxane (MAO). The catalytic system afforded well-defined PME copolymers and novel PMEI terpolymers with controlled compositions (up to 49% of terpene incorporated in the case of PME). Microstructural analysis demonstrated high stereoselectivity of 1, with 1,4-<i>trans</i> insertion predominating for both isoprene (97%) and myrcene (94%). A comprehensive analysis by ¹³C and 2D NMR techniques confirmed a multi-block architecture for the novel synthesized copolymers. Notably, PMEI terpolymers exhibited a strong tendency toward forming alternating ethylene-isoprene (E-I) sequences. The thin film morphology, investigated by tapping mode atomic force microscopy (AFM), for the PME and PMEI copolymers, evidenced a phase-separated morphology consisting of soft and hard phases, respectively, ascribed to polydienic and polyethylenic domains. The materials displayed glass transition temperatures ranging from -62 to -74 °C, demonstrating their potential as sustainable and high-performance elastomers.</p>","PeriodicalId":76,"journal":{"name":"Faraday Discussions","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2025-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145111617","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Supramolecular interactions in softwood kraft lignin nanoparticles.","authors":"Massimo Sgarzi, Matteo Gigli, Shahzal Babar, Nicolò Pajer, Giorgia Peroni, Claudia Crestini, Nina Tverdokhleb, Arezoo Dianat, Rafael Gutierrez, Gianaurelio Cuniberti","doi":"10.1039/d5fd00076a","DOIUrl":"https://doi.org/10.1039/d5fd00076a","url":null,"abstract":"<p><p>The production of functional (nano)materials based on lignin as a renewable starting material depends on the thorough understanding of lignin's physico-chemical properties, among which self-assembly and agglomeration/aggregation are the most important. Nevertheless, the knowledge about the structure-property relations for lignin is still in its infancy and needs further in-depth investigations. In this context, this works focuses on the study of the size and the colloidal stability of lignin nanoparticles (LNPs) prepared from softwood kraft lignin (SKL) using the solvent-antisolvent method. Conformational rearrangements of lignin chains were found to contribute significantly to the formation of the first lignin nuclei. The slow addition of ethylene glycol and THF into water caused the formation of nuclei with low aggregation numbers, minimizing the hydrodynamic volume of the final LNPs. On the other hand, a quick addition of these organic solvents created spatially and temporally higher lignin concentrations, yielding nuclei with high aggregation numbers and larger hydrodynamic volumes. Molecular dynamics simulations revealed the major role of intramolecular and intermolecular hydrogen bonds in this process, together with the contribution from π-π stacking interactions. The superficial concentration of phenolic and condensed guaiacyl units was found to strongly influence the corresponding LNPs' zeta-potential values. Altogether, these results shed further light on the properties of colloidal lignin with a view to enabling its full potential as a key material for technological applications.</p>","PeriodicalId":76,"journal":{"name":"Faraday Discussions","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2025-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145084624","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of bottom-up and top-down precipitation strategies for lignin nanoparticle obtention from organosolv and ionosolv <i>Eucalyptus globulus</i> liquors.","authors":"Victoria Rigual, Antonio Ovejero-Pérez, Antonio Martínez-Mangas, Beatriz García-Sánchez, Juan C Domínguez, M Virginia Alonso, Mercedes Oliet, Francisco Rodriguez","doi":"10.1039/d5fd00070j","DOIUrl":"https://doi.org/10.1039/d5fd00070j","url":null,"abstract":"<p><p>This work offers a side-by-side overview of the behaviour of two liquors obtained <i>via</i> two fractionation processes, ionosolv and organosolv, from <i>Eucalyptus globulus</i> wood, and how the precipitation strategy that follows may affect the final yield, morphology, and particle size of every kind of lignin nanoparticle. For lignin nanoparticle precipitation, two bottom-up techniques and two top-down approaches were employed to determine which combination of fractionation process and synthesis treatment would provide the nanoparticles with the best characteristics. The results demonstrated the importance of the fractionation process in the final lignin nanoparticle yield, as ionosolv fractionation gave enhanced yields of more than 60% lignin in the form of nanoparticles. However, sphericity, particle sizes, and non-agglomerated structures were easily obtained from organosolv liquors, in which precipitation was carried out progressively in the absence of sonication. The use of ultrasound mostly resulted in the breakage of particles into smaller and irregular pieces. However, in the case of ionosolv liquors, homogeneous spherical nanoparticles were fused, forming agglomerates of smaller particles through the top-down strategy of complete addition of the antisolvent followed by sonication. The highest precipitation yield of nanoparticles was obtained from ionosolv liquors in which the full amount of antisolvent was added in one step to precipitate lignin, and then sonication was applied. In contrast, the lignin nanoparticles (LNPs) precipitation strategy that resulted in more spherical LNPs was the bottom-up strategy of precipitation by progressive antisolvent addition, resulting in visually observed non-aggregated spherical particles with a particle size distribution of 200 nm < <i>d</i>_p < 500 nm, molecular weight of <i>M</i>_w = 14 000 g mol^-1, and thermal degradation property of <i>T</i>_10% = 310 °C.</p>","PeriodicalId":76,"journal":{"name":"Faraday Discussions","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2025-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145084481","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Selective transesterification mediated by lanthanum complexes in the copolymerisation of lactide and δ-valerolactone.","authors":"Richard J Pearcy, Stuart R Berrow, Rachel H Platel","doi":"10.1039/d5fd00055f","DOIUrl":"https://doi.org/10.1039/d5fd00055f","url":null,"abstract":"<p><p>Poly(lactide-<i>co</i>-valerolactone) copolymers were prepared <i>via</i> the one-pot copolymerisation of <i>rac</i>-lactide or <i>S</i>,<i>S</i>-lactide with δ-valerolactone at ambient temperature, mediated by bis(dimethylsilyl)amido lanthanum complexes supported by ligands derived from a salan framework (salan = <i>N</i>,<i>N</i>'-bis(<i>o</i>-hydroxy, <i>m</i>-di-<i>tert</i>-butylbenzyl)-1,2-diaminoethane), which incorporate either benzyl or 2-pyridyl groups at the tertiary amine moieties. Poly(δ-valerolactone)s were also prepared by the ring-opening polymerisation of δ-valerolactone and high molecular weight polymers (up to 83.6 kg mol^-1) with narrow dispersities were obtained. The poly(lactide-<i>co</i>-valerolactone) copolymers were fully characterized using ¹H and ¹³C NMR spectroscopy, gel-permeation chromatography and differential scanning calorimetry. Both the reaction solvent (toluene or THF) and the number of 2-pyridyl groups the complex possesses affect the complex activity and copolymer microstructure. The use of a non-coordinating solvent and presence of at least one 2-pyridyl group is required for high conversion of both monomers. Variation of the monomer feed ratio allowed copolymers across the full compositional range to be prepared. The copolymers are formed <i>via</i> a transesterification mechanism whereby all of the lactide undergoes rapid polymerisation in the early stages of the reaction and the δ-valerolactone is subsequently incorporated into the polymer. The rate and extent of δ-valerolactone polymerisation increases with the number of 2-pyridyl groups in the catalyst in toluene and is more rapid in non-coordinating solvent (toluene) than coordinating solvent (THF). Only low levels of the <i>T</i>_II mode of transesterification occur, with the <i>T</i>_I transesterification mode dominating, leading to the formation of copolymers with intact lactidyl units.</p>","PeriodicalId":76,"journal":{"name":"Faraday Discussions","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2025-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145084530","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Self-assembled poly(L-lactide)-based platelets prepared <i>via</i> seeded growth.","authors":"Laihui Xiao, Tianlai Xia, Rachel K O'Reilly","doi":"10.1039/d5fd00064e","DOIUrl":"https://doi.org/10.1039/d5fd00064e","url":null,"abstract":"<p><p>Crystallization-driven self-assembly (CDSA) offers a powerful approach for constructing well-defined nanostructures; however, achieving precise control over two-dimensional (2D) platelet formation remains challenging, particularly for poly(L-lactide) (PLLA). In this work, we developed a seeded growth strategy using a mixture of homopolymers and diblock polymers to prepare PLLA platelets. In this system, homopolymers facilitate the formation of 2D platelets and enhance crystallization kinetics, while diblock polymers stabilize the platelets and provide functional moieties through their corona-forming block. By systematically optimizing temperature, polymer composition, and polymer length, we achieved size-controllable platelets. Furthermore, we successfully transferred the platelet preparation from batch to a continuous flow system to enable scalable production. This study contributes to the advancement of biodegradable and biocompatible nanoparticles, offering new possibilities for their application in biomedical and functional materials.</p>","PeriodicalId":76,"journal":{"name":"Faraday Discussions","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2025-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145084674","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Understanding depolymerization kinetics of poly(butyl methacrylate) using flow chemistry.","authors":"Leonard P M Göhringer, Gayathri Dev Ammini, Tanja Junkers","doi":"10.1039/d5fd00049a","DOIUrl":"https://doi.org/10.1039/d5fd00049a","url":null,"abstract":"<p><p>Reversible addition-fragmentation chain-transfer (RAFT) depolymerization offers a promising and (comparatively) low-temperature chemical recycling strategy, enabling high yields of recovery of monomers. Conducting this process under continuous flow conditions, in combination with an inline dialysis set-up was recently demonstrated to accelerate depolymerization. However, several kinetic aspects of the process remain poorly understood, complicating the optimization of flow processes. In this study, we determined the kinetics of RAFT depolymerization under continuous flow conditions on the example of poly(butyl methacrylate), polyBMA. Depolymerizations were followed at temperatures from 120 °C to 160 °C, and the activation energy of the process was determined to be 79.5 kJ mol^-1. Further, a square root dependence of the rate on the initial polymer concentration was determined. Comparison of the rates of depolymerization with clearance rates during in-flow membrane dialysis showed that the dialysis process is, by a large margin, the rate-determining step in the entire process. Removal of monomer was accelerated by increasing the cross-flow rate in the dialysis, providing a first step towards optimal conditions in the flow depolymerization.</p>","PeriodicalId":76,"journal":{"name":"Faraday Discussions","volume":" ","pages":""},"PeriodicalIF":3.1,"publicationDate":"2025-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145079216","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}