Macromolecules最新文献

{"title":"Uncovering Backbone Conformation for Rigid DPP-Based Donor–Acceptor Conjugated Polymer Using Deuterium Labeling and Neutron Scattering","authors":"Zhiqiang Cao, Zhaofan Li, Madison Mooney, Changwoo Do, Kunlun Hong, Simon Rondeau-Gagné, Wenjie Xia, Xiaodan Gu","doi":"10.1021/acs.macromol.4c01496","DOIUrl":"https://doi.org/10.1021/acs.macromol.4c01496","url":null,"abstract":"The conjugated polymer’s backbone conformation dictates the delocalization of electrons, ultimately affecting its optoelectronic properties. Most conjugated polymers can be viewed as semirigid rods with their backbone embedded among long alkyl side chains. Thus, it is challenging to experimentally quantify the conformation of a conjugated backbone. Here, we performed contrast variation neutron scattering on rigid conjugated donor–acceptor (D–A) diketopyrrolopyrrole (DPP) polymers with selectively deuterated side chains to measure the conjugated backbone conformation. We first synthesized DPP-based polymers with deuterated side chains, confirmed by NMR and FTIR. Using contrast variation neutron scattering, we found that the DPP-based conjugated polymers are much more rigid than poly(3-alkylthiophenes), with persistence length (<i>L</i>_p) at 16–18 nm versus 2–3 nm. More importantly, in contrast to the relatively flexible poly(3-alkylthiophenes) whose backbone is more flexible than the whole polymer, we found that the backbone of DPP-based polymers has the same <i>L</i>_p value compared to the whole polymer chain. This indicates that side chain interference on backbone conformation is not present for the semirigid polymer, which is further confirmed by coarse-grained molecular dynamics (CG-MD) simulations. Our work provides a novel protocol to probe polymer’s backbone conformation and paradigm-shifting understanding of the backbone conformation of semirigid conjugated polymers.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":null,"pages":null},"PeriodicalIF":5.5,"publicationDate":"2024-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142452352","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Identification and Design of Better Diamine-Hardened Epoxy-Based Thermoset Shape Memory Polymers: Simulation and Machine Learning","authors":"Anwar Shafe, Pouria Nourian, Xiyuan Liu, Guoqiang Li, Collin D. Wick, Andrew J. Peters","doi":"10.1021/acs.macromol.4c01598","DOIUrl":"https://doi.org/10.1021/acs.macromol.4c01598","url":null,"abstract":"An approach for designing thermoset shape memory polymers (TSMPs) with improved shape memory properties through the integration of molecular dynamics (MD) simulation, machine learning (ML), and chemical intuition is presented. We identified key molecular features correlated with desired shape memory properties, and used MD simulations to create an initial data set of TSMPs consisting of commercially available and manually designed monomers. Our prediction set was prepared by employing four different approaches for modifying existing monomers based on chemical intuition and insights gleaned from the literature. We trained our ML model on the initial data set, used it to identify the most promising candidates, evaluated their properties, and added them to our initial data set. To further speed up the process, we identified the most promising candidate after a few cycles and modified its structure to obtain a variant with better properties. Our approach, which capitalizes on the synergy between computational methodologies and human expertise to enable efficient exploration of vast chemical space, resulted in the design of a monomer exhibiting more than 60% increase in the desired recovery stress compared to the highest experimentally validated one.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":null,"pages":null},"PeriodicalIF":5.5,"publicationDate":"2024-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142452350","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Trifluoromethylated N,S-Acetal as a Chemical Platform for Covalent Adaptable Networks: Fast Thiol Exchange and Strong Hydrostability for a Highly Transparent Material","authors":"Sidonie Laviéville, Cédric Totée, Pascale Guiffrey, Sylvain Caillol, Camille Bakkali-Hassani, Vincent Ladmiral, Eric Leclerc","doi":"10.1021/acs.macromol.4c01359","DOIUrl":"https://doi.org/10.1021/acs.macromol.4c01359","url":null,"abstract":"This work presents the synthesis and characterization of a highly transparent and colorless covalent adaptable network (CAN) exhibiting short relaxation times (30 s at 150 °C) and limited creep at 100 °C. Based on <i>N,S</i>-acetal functions, strongly stabilized by a trifluoromethyl group, this network, however, retains the ability to undergo fast thiol exchanges. The present article describes a detailed monitoring of the cross-linking via ATR-FTIR and ¹⁹F HRMAS NMR (high-resolution magic angle spinning NMR), the complete structural characterization of the material via ¹³C HRMAS NMR, and the comprehensive study of the rheological properties of this novel <i>N,S</i>-acetal network. This CAN shows hydrolytic stability and higher activation energies (&gt;90 kJ mol^–1) than its nonfluorinated counterparts. Its reprocessing occurs under relatively mild conditions without the need for a catalyst, and depolymerization can be achieved either with an amine (benzylamine), under acidic conditions (1 M HCl) at room temperature, or with a thiol (1-dodecanethiol) at 100 °C.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":null,"pages":null},"PeriodicalIF":5.5,"publicationDate":"2024-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142450062","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Designing Novel All-Polymer Nanocomposites with Pearl Necklace Chain Structure with High Strength, High Toughness, and Low Hysteresis","authors":"Tongkui Yue, Xin Zou, Hengheng Zhao, Yulong Chen, Liqun Zhang, Jun Liu","doi":"10.1021/acs.macromol.4c01486","DOIUrl":"https://doi.org/10.1021/acs.macromol.4c01486","url":null,"abstract":"Service performance can be significantly improved by adding nanofillers into polymers. However, entropy effects and enthalpic interactions between traditional inorganic fillers and polymers impede the simultaneous attainment of high strength and strong toughness. Polymer-based soft nanoparticles (SNPs) have emerged as promising candidates for achieving a balance between strength and toughness. To fully harness the deformability potential of SNPs and achieve superior mechanical performance, the pearl necklace structure was designed by employing molecular dynamics simulation. Compared to traditional all-polymer nanocomposite system (S&lt;sub&gt;T&lt;/sub&gt;) composed of directly mixing polymer and SNPs, the SNPs in our novel system (S&lt;sub&gt;N&lt;/sub&gt;) exhibit better dispersion and compatibility. Primitive path analysis revealed that the pearl necklace chains endow a greater degree of penetration between SNPs and polymer. The confinement effects of cross-linking networks alter the diffusion dynamics of SNPs embedded within polymer chains. The restricted displacement fluctuation distance &lt;i&gt;&lt;/i&gt;&lt;span style=\"color: inherit;\"&gt;&lt;/span&gt;&lt;span data-mathml='&lt;math xmlns=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"&gt;&lt;msubsup&gt;&lt;mrow&gt;&lt;mi&gt;d&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi&gt;fluct&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mi&gt;SNP&lt;/mi&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/msubsup&gt;&lt;/math&gt;' role=\"presentation\" style=\"position: relative;\" tabindex=\"0\"&gt;&lt;nobr aria-hidden=\"true\"&gt;&lt;span style=\"width: 2.513em; display: inline-block;\"&gt;&lt;span style=\"display: inline-block; position: relative; width: 2.052em; height: 0px; font-size: 122%;\"&gt;&lt;span style=\"position: absolute; clip: rect(1.13em, 1002.05em, 2.615em, -999.997em); top: -2.2em; left: 0em;\"&gt;&lt;span&gt;&lt;span&gt;&lt;span style=\"display: inline-block; position: relative; width: 2.052em; height: 0px;\"&gt;&lt;span style=\"position: absolute; clip: rect(3.128em, 1000.51em, 4.152em, -999.997em); top: -3.993em; left: 0em;\"&gt;&lt;span&gt;&lt;span style=\"font-family: MathJax_Math-italic;\"&gt;d&lt;span style=\"display: inline-block; overflow: hidden; height: 1px; width: 0.003em;\"&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;span style=\"display: inline-block; width: 0px; height: 3.998em;\"&gt;&lt;/span&gt;&lt;/span&gt;&lt;span style=\"position: absolute; clip: rect(3.332em, 1001.49em, 4.152em, -999.997em); top: -4.403em; left: 0.566em;\"&gt;&lt;span&gt;&lt;span&gt;&lt;span style=\"font-size: 70.7%; font-family: MathJax_Main;\"&gt;SNP&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;span style=\"display: inline-block; width: 0px; height: 3.998em;\"&gt;&lt;/span&gt;&lt;/span&gt;&lt;span style=\"position: absolute; clip: rect(3.332em, 1001.49em, 4.152em, -999.997em); top: -3.737em; left: 0.515em;\"&gt;&lt;span&gt;&lt;span&gt;&lt;span style=\"font-size: 70.7%; font-family: MathJax_Main;\"&gt;fluct&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;span style=\"display: inline-block; width: 0px; height: 3.998em;\"&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;span style=\"display: inline-block; width: 0px; height: 2.205em;\"&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;span style=\"display: inline-block; ove","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":null,"pages":null},"PeriodicalIF":5.5,"publicationDate":"2024-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142450058","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mixed Isodimorphic/Isomorphic Crystallization in Aliphatic Random Copolycarbonates","authors":"Yilong Liao, Ricardo A. Pérez-Camargo, Tianyi Ma, Jon Maiz, Antxon Martínez de Ilarduya, Haritz Sardon, Guoming Liu, Dujin Wang, Alejandro J. Müller","doi":"10.1021/acs.macromol.4c01716","DOIUrl":"https://doi.org/10.1021/acs.macromol.4c01716","url":null,"abstract":"In this work, we investigate the crystallization behavior of two series of novel aliphatic random copolycarbonates: poly(heptamethylene-<i>ran</i>-octamethylene carbonate) (PC7/PC8) and poly(octamethylene-<i>ran</i>-dodecamethylene carbonate) (PC12/PC8). Both copolymers display apparent isodimorphic behavior as they crystallize over the entire composition range, exhibiting pseudoeutectic points at 45 and 76 mol % of PC8 content for PC7/PC8 and PC12/PC8, respectively. However, the evolution in melting enthalpies (Δ<i>H</i>_m) and crystallinities (<i>X</i>_<i>c</i>) deviate from the expected pseudoeutectic behavior, indicating mixed isodimorphic/isomorphic crystallization, a behavior reported for the first time recently by us in poly(hexamethylene-<i>ran</i>-octamethyelene carbonate) (PC6/PC8). Further understanding of this behavior was obtained through structural and conformational characterization employing in situ synchrotron radiation wide- and small-angle X-ray scattering (WAXS/SAXS) and Fourier-transform infrared spectroscopy (FT-IR). For PC7/PC8 copolymers, a new third crystalline phase, from now on named the γ phase, different from PC7- and PC8-type crystalline phases (or any of their polymorphs: δ, α, and β), emerged for intermediate compositions, i.e., 34–45 mol % PC8, in line with the atypical variations of Δ<i>H</i>_m and <i>X</i>_c. For PC12/PC8 copolymers, a coexistence of the γ/PC8 type phase was found at PC8-rich contents. According to FT-IR results, the γ phase adopted a polyethylene-like conformation in all cases despite the presence of C═O groups. However, compared with those compositions where homopolymer-like phases dominate the crystallization, there is a stronger dipole–dipole interaction in the γ phase, evidenced by a shift of absorption band associated with C═O stretching. This evidence aligns with our previous work in PC6/PC8 copolymers, demonstrating that the mixed isodimorphic/isomorphic crystallization found in PC8-based random copolycarbonates is likely a general case. Additionally, as the number of methylene groups in the repeating unit of the second comonomer in the PC8-based copolymers increases, the composition range where the γ phase is observed narrows. At the same time, the position of the pseudoeutectic point shifts toward compositions rich in PC8, demonstrating how the chemical structure affects the exact location of the pseudoeutectic point in these random copolycarbonates.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":null,"pages":null},"PeriodicalIF":5.5,"publicationDate":"2024-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142448179","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fast Gelation and Mechanical Reinforcement of Tetrahydroxydiboron-Induced Free Radical Polymerized Hydrogels under Harsh Conditions","authors":"Yi Wang, Wanting Yuan, Qianqian Liang, Hongyi Lv, Xiaoting Liu, Lijuan Zhao, Jinrong Wu","doi":"10.1021/acs.macromol.4c01654","DOIUrl":"https://doi.org/10.1021/acs.macromol.4c01654","url":null,"abstract":"Hydrogels prepared through free radical polymerization hold great promise for large-scale production and practical applications but face challenges due to oxygen inhibition during polymerization and poor mechanical properties. These issues often necessitate complex structural designs and time-consuming anaerobic processes. This work presents a novel approach using tetrahydroxydiboron (THDB) combined with potassium persulfate (KPS) to rapidly produce hydrogels with enhanced mechanical properties under aerobic conditions, overcoming traditional limitations. The THDB-KPS system facilitates the gelation of acrylamide (AM) precursors in just 2 min under ambient conditions, significantly outperforming existing systems. This method is versatile across various monomer types, including hydrophilic, electrolyte, macromolecular and zwitterionic monomers. This rapid gelation effect stems from the THDB’s ability to interact with dissolved oxygen to neutralize the inhibitory effects of oxygen, and to promote persulfate decomposition efficiently by homolytic cleavage to produce (HO)₂B· radicals through the coordination of N or O in the vinyl monomers with the diboron structure. Meanwhile, boron-induced hydrogen bonding and coordination interactions, along with the fast rise in temperature and viscosity of the reaction system, contribute to the shortened gelation time as well. These factors also lead to the formation of multiple physical cross-links as well as a network of densely and loosely cross-linked regions. Consequently, the mechanical properties of the hydrogel are significantly enhanced through the progressive deformation of these densely and loosely cross-linked regions along with the breakage of physical cross-links. This rapid gelation and mechanical reinforcement effect remains effective even under challenging conditions, including acidic or alkaline environments, low temperatures and impurity-laden environments. Therefore, this breakthrough offers a scalable and efficient method for producing high-performance hydrogel under harsh conditions, promising substantial advancements in industrial applications and practical use in diverse fields.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":null,"pages":null},"PeriodicalIF":5.5,"publicationDate":"2024-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142449660","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Flash Flow-Induced Crystallization of Poly(l-lactide) under Elevated Pressure during Industrial-Scale Injection Molding Revealed by Time-Resolved Synchrotron X-ray Scattering","authors":"Jin Yin, Jie Zhang, Zheng-Yuan Chen, Lu-Feng Deng, De-Zhuang Jia, Hao Lin, Jia-Zhuang Xu, Hua-Dong Huang, Jun Lei, Gan-Ji Zhong, Zhong-Ming Li","doi":"10.1021/acs.macromol.4c01570","DOIUrl":"https://doi.org/10.1021/acs.macromol.4c01570","url":null,"abstract":"Poly(<span>l</span>-lactide) (PLLA) is a promising biodegradable alternative to petroleum-based plastics, but it exhibits slow crystallization kinetics. Understanding flow-induced crystallization under pressure (FICP) during practical polymer processing, such as injection molding, is important to tailor the crystallization and modulate the properties. Compared with the traditional “black-box” research on FICP, understanding the multistep FICP of PLLA during industrial-scale injection molding and the effect of external fields on crystallization <i>via</i> real-time mode is crucial for revealing the underlying mechanism. This work first pays attention to the FICP process of PLLA during industrial-scale injection molding <i>via</i> a homemade in situ investigation platform base-d on a highly brilliant synchrotron X-ray scattering. We find that an initial flash flow (shear time ∼0.1 s) with extremely intense flow (Weissenberg number <i>Wi</i> ≫ 1) induces α/α′-form and β-form precursors in the PLLA melt, and subsequent crystallization around the oriented precursors occurs under quasi-isothermal and residual-pressure conditions. In particular, the elevated packing pressure observably promotes flow-induced oriented precursors and especially the β-form nucleates preferentially, while the segmental diffusion-dominant retardant crystal growth proceeds during the following quasi-isothermal crystallization. Being composed of thicker lamellae with a higher amount, the injection-molded PLLA bars under low pressure exhibit superior mechanical strength and thermomechanical performance. The outcome of this work points out that the pressure field is of great importance in flow-induced crystallization kinetics and the final crystalline morphology, which is valuable for guiding the development of a high-performance PLLA product and expanding its applications.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":null,"pages":null},"PeriodicalIF":5.5,"publicationDate":"2024-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142444371","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"One-Component Stilbene-Based Iodonium Photoinitiators with Increased Photoacid Quantum Yield for Cationic Vat 3D Printing","authors":"Filip Petko, Magdalena Jankowska, Mariusz Galek, Małgorzata Noworyta, Roman Popielarz, Joanna Ortyl","doi":"10.1021/acs.macromol.4c01692","DOIUrl":"https://doi.org/10.1021/acs.macromol.4c01692","url":null,"abstract":"New advanced iodonium salts based on stilbene chromophores with significantly improved photoinitiating properties are presented. The extended conjugated double bond system provides major improvement in quantum yield of superacid generation (up to 10 times higher compared to benzylidene-based iodonium salts) while maintaining absorption properties in UV-A and visible light. The newly developed iodonium salts exhibit photoinitiating activity toward cationically polymerizable monomers such as cyclic epoxy monomers (e.g., 3,4-epoxycyclohexylmethyl 3,4-epoxycyclohexane-carboxylate (CADE)), oxetanes (e.g., bis[1-ethyl(3-oxetanyl)]methyl ether (OXT-221)) and glycidyl ether monomers (e.g., diglycidyl ether of bisphenol A (DGEBA)) under the irradiation by light-emitting diodes (LEDs) emitting at 365, 405 and even 430 nm, with no additives. Commonly used diaryliodonium photoinitiators are inactive under those irradiation wavelengths. Moreover, some of the new iodonium salts are also able to photoinitiate free radical photopolymerization of the acrylate monomers, such as trimethylolpropane triacrylate (TMPTA). Such high photoinitiating activity allows these salts to be used as one-component photoinitiators in cationic vat 3D printing of nanocomposites at ambient temperature. The resolution of the cationic prints was limited mainly by the DLP 3D printer and monomers, with slight signs of overpolymerization.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":null,"pages":null},"PeriodicalIF":5.5,"publicationDate":"2024-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142444374","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Toughening Rubber by In Situ Construction of Hierarchical Coordination Complexes with a Sulfur-Based Ionomer","authors":"Senmao Yu, Zhenghai Tang, Dong Wang, Baochun Guo, Liqun Zhang","doi":"10.1021/acs.macromol.4c01907","DOIUrl":"https://doi.org/10.1021/acs.macromol.4c01907","url":null,"abstract":"Programming energy-dissipating units into polymers is an effective method to improve the toughness; however, the state-of-art approaches usually involve complicated chemistry manipulation and multistep process. In this contribution, we report a brand-new way to toughen styrene–butadiene rubber (SBR) by incorporating a sulfur-based ionomer to construct hierarchical coordination complexes. Specifically, the ionomer P(TA-S)/Fe containing polysulfide backbones and iron–carboxylate complexes was synthesized through the copolymerization of thioctic acid and sulfur, followed by introducing ferric chloride. Due to the reaction between polysulfide fragments in P(TA-S)/Fe and SBR, the incorporation of P(TA-S)/Fe enabled the chemical cross-linking of SBR and grafting of iron–carboxylate complexes onto SBR chains. The grafted iron–carboxylate complexes aggregated and formed a phase separate structure within SBR, which provided a multilevel energy-dissipating mechanism and consequently led to an integration of enhanced ultimate strength, modulus, and fracture toughness of SBR.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":null,"pages":null},"PeriodicalIF":5.5,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142444373","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tailoring Polymer Polarity to Regulate Disulfide Accessibility in Redox-Active Particles for Organic Batteries","authors":"Hongyi Zhang, Garrett L. Grocke, George Rose, Stuart J. Rowan, Shrayesh N. Patel","doi":"10.1021/acs.macromol.4c01894","DOIUrl":"https://doi.org/10.1021/acs.macromol.4c01894","url":null,"abstract":"This study seeks to explore the relationship between particle polarity and the electrochemical accessibility of organo-disulfide-based redox-active particles. Micron-sized poly(glycidyl methacrylate) (PMGA) particles were synthesized and subsequently cross-linked with thiadiazole disulfide to produce redox-active particles (DS-RAPs). The residual glycidyl units underwent reactions with various side chains to modulate the polarity of the DS-RAPs. These side chains vary from nonpolar aliphatic <span><i>N</i></span>-methylbutylamine (MBA) to the more polar oligoethylene glycol amine (EGA) and glycidyl carbonate (GC) moieties. Cyclic voltammetry reveals that functionalization with polar side chains enhances electrochemical accessibility, with DS-RAP_GC demonstrating the highest accessibility in both acetonitrile and tetraglyme-based electrolytes. Testing the DS-RAP derivatives as cathode electrodes in a lithium cell with a LiTFSI/tetraglyme electrolyte indicates that DS-RAP_GC yields the highest specific capacities, energy efficiency, and best kinetics at 0.1C. Conversely, C-rate dependence measurements show that DS-RAP_EGA has higher specific capacities at faster C-rates and is more resilient to mass transport limitations compared to DS-RAP_GC and DS-RAP_MBA. This is attributed to greater electrolyte swelling in DS-RAP_EGA and higher ion diffusivity, as evidenced by galvanostatic intermittent titration technique (GITT) measurements. Lastly, long-term cycling tests at 0.1C indicate minimal degradation, with the resulting capacity fade attributed to charge trapping during the continuous reversible oxidation/reduction of disulfides. Overall, these findings contribute significantly to the development of effective RAPs for energy storage applications, highlighting the pivotal role of chemical modifications via side chain engineering in controlling particle polarity to enhance charge transport and overall electrochemical performance.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":null,"pages":null},"PeriodicalIF":5.5,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142440652","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}