Macromolecules最新文献

{"title":"Physical and Chemical Responses of Amidine-Containing Polymers in the Capture and Release of CO2","authors":"Danielle J. Chun, Abigail Mccord, Narges Mokhtari-Nori, Sheng Dai, John Z. Larese, Luke L. Daemen, Bradley S. Lokitz, S. Michael Kilbey, II","doi":"10.1021/acs.macromol.4c01782","DOIUrl":"https://doi.org/10.1021/acs.macromol.4c01782","url":null,"abstract":"Polymeric materials containing amidine motifs are of high interest due to their ability to reversibly capture and release CO₂ at ambient temperature. Here we probe physical and chemical responses of styrene-based copolymers containing linear amidine motifs as functions of CO₂ and inert gas exposures and temperature. A copper-catalyzed azide–alkyne cycloaddition “click” reaction involving <i>N</i>′-propargyl-<i>N</i>,<i>N</i>-dimethylacetamidine is used to modify random copolymers, resulting in an array of linear amidine motifs along the chain backbone with the amount of CO₂-active amidine controlled by the copolymer composition. Through thermogravimetric measurements, we demonstrate that the amidine-functionalized copolymers efficiently capture CO₂ upon exposure to a stream of CO₂ (at 27 °C) and release it at a slightly elevated temperature (50 °C) when exposed to an inert gas stream (N₂). In addition to displaying a maximum adsorption capacity of 22 wt % in the presence of pure CO₂, the copolymers show composition-dependent direct air capture (DAC) behaviors. Small molecule analogs are used to definitively understand degradation via chemical hydrolysis of the amidine moiety, which leads to insolubility and a large reduction in CO₂ adsorption capacity (1.7 wt %). Neutron vibrational spectroscopy and DFT calculations confirm that CO₂ binds strongly to the amidine motif, inducing a strong bending of the CO₂ molecule from its linear geometry. The coupled insights into mechanisms and behaviors of CO₂ adsorption in amidine-functionalized polymers provides a foundation for future investigations of CO₂-responsive polymers and soft materials to improve carbon capture and sequestration technologies.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"33 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142678674","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":"N-Sulfonyl Guanidine Urea to Design Ultrastrong, Stable, and Recyclable Associative Dynamic Polyurea Networks","authors":"Zhen Yu, Yanlin Liu, Sheng Wang, Yajin Fang, Xiangyu Zhou, Zhaobin Tang, Jin Zhu, Junping Zhang","doi":"10.1021/acs.macromol.4c01575","DOIUrl":"https://doi.org/10.1021/acs.macromol.4c01575","url":null,"abstract":"Dynamic covalent adaptive networks can solve the recycling issue of thermosets. However, dissociative dynamic covalent networks may suffer from instability and network incompleteness at high temperatures or in solvents. Here, we report a novel dynamic covalent bond, <i>N</i>-sulfonyl guanidine urea (SGUA), that can undergo catalyst-free metathesis reactions, in which a passivation strategy of increasing the dissociation temperature of guanidine urea by introducing electron-withdrawing <i>N</i>-sulfonyl groups into adjacent positions was developed. Unlike conventional dissociative dynamic urea bonds, SGUAs exhibit associative metathesis reactions at around 120–180 °C, with a high dissociation threshold of 180 °C. The dynamic covalent polyurea constructed by SGUAs, named PSGUAs, exhibits ultrastrong (Young’s modulus exceeding 4 GPa and tensile strength exceeding 60 MPa) and stable (thermal stability, network structure integrity under reprocessing, and dimensional stability) performances. Furthermore, due to the excellent dynamic characteristics of SGUAs, PSGUAs were successfully reprocessed after 30–60 min of hot pressing at 160 °C and 20 MPa. Combining the long-lasting antibacterial properties of PSGUAs with long-term use, this study marks a substantial improvement in the field of dynamic polymer networks, giving a solution for balancing material stability, high performance, and reprocessability.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"42 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142679127","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":"Solvent Exchange-Induced Microphase Separation and Structural Arrest to Form Glassy Hydrogels","authors":"Jia Yu Hu, Li Xin Hou, Ao Zhu, Hao Nan Qiu, Zi Rong Zhang, Cong Du, Kunpeng Cui, Qiang Zheng, Zi Liang Wu","doi":"10.1021/acs.macromol.4c01758","DOIUrl":"https://doi.org/10.1021/acs.macromol.4c01758","url":null,"abstract":"Glassy hydrogels with high stiffness and toughness have been developed in recent years by forming dense associative interactions in a gel matrix. There are several reports on forming robust hydrophobic associations with microphase separation during the solvent exchange process to convert elastic organogels to glassy hydrogels. However, the microstructure formation during the solvent exchange process and the mechanism accounting for rubbery-to-glassy transition of the gels remain unclear. In this study, we copolymerize hydrophobic ethylene glycol phenyl ether acrylate and hydrophilic methacrylic acid in dimethyl sulfoxide, followed by solvent exchange with water to form glassy hydrogels with microphase-separated structures. Ultrasmall- and small-angle X-ray scattering measurements are performed on the gel during the solvent exchange process at various temperatures, and structural parameters are ascertained to trace the structural evolution of the gel. A two-stage structural formation mechanism is proposed for the varying microstructure and properties of the gel during the solvent exchange process. At the initial stage, segregation of hydrophobic segments leads to microphase separation that creates a bicontinuous structure with a high-viscosity polymer-rich phase. At the late stage, the polymer-rich phase becomes vitrified, which arrests the microphase separation and produces a glassy hydrogel far from the thermodynamic equilibrium state. The metastability nature of glassy gel can be harnessed to mediate the microstructure and properties by hydrothermal treatment to reactivate the phase separation. This study provides insights into the interaction between microphase separation and vitrification that determines the structure and properties of glassy gels, which will merit the design of high-performance soft materials with phase-separated structures.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"57 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142678672","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":"Decisive Role of the Specific Nanosized Secondary Crystals on the Phase Transition of Poly(vinylidene fluoride) Induced by Melt Memory","authors":"Yufei Dong, Xin Zhang, Houyin Long, Alejandro J. Müller, Lei Zhu, Xiaoli Sun, Shouke Yan","doi":"10.1021/acs.macromol.4c01678","DOIUrl":"https://doi.org/10.1021/acs.macromol.4c01678","url":null,"abstract":"Nanosized crystals induced by secondary crystallization are common occurrences in semicrystalline polymers. However, their significance is often overlooked due to their small proportion and the difficulty in distinguishing them from primary crystals (PCs). This study selected poly(vinylidene fluoride) (PVDF) as a model system. We distinguished the thickness of the SCs from that of the PCs based on small-angle X-ray scattering data and further built the relationship between the melt memory of α-PVDF materials and the crystallinity of nanosized α-phase SCs by adjusting the end crystallization temperature. Notably, these nano α-SCs exhibit a remarkable role in transitioning from TGTG′ to T₃GT₃G′ conformation during their partial melting and subsequent cooling process. The conformational transition stemming from the partial melting of the SCs effectively promotes the transition from the nonpolar α-phase to the polar γ-phase. The observed phase transition can be attributed to the matching between the melting thermal dynamics of α-SCs and the thermal dynamics of the conformational transition within amorphous chains. Our findings underscore the significant effect of moderate nanosized SCs on the phase transformation and introduce a practical and effective methodology for producing polar-phase PVDF materials.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"23 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2024-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142670767","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":"Engineering Pyreno[1,2-b:8,7-b′]dithiophene-Based Conjugated Polymers for Efficient and Stable Perovskite Solar Cells","authors":"Yaohang Cai, Lifei He, Lingyi Fang, Yuyan Zhang, Jing Zhang, Yi Yuan, Peng Wang","doi":"10.1021/acs.macromol.4c02206","DOIUrl":"https://doi.org/10.1021/acs.macromol.4c02206","url":null,"abstract":"The advancement of p-type conjugated polymers with optimized electrical properties, morphology, and heat tolerance is essential for n-i-p-type perovskite solar cells. Herein, we present a novel conjugated polymer, p-PDT₁₄4-E, composed of alternating units of 4,4,7,7-tetrakis(4-hexylphenyl)-4,7-dihydropyreno[1,2-<i>b</i>:8,7-<i>b</i><i>′</i>]dithiophene (PDT₁₄4) and 3,4-ethylenedioxythiophene. This copolymer was synthesized via a palladium-catalyzed direct arylation polycondensation method. Compared to the corresponding homopolymer p-PDT₁₄4 synthesized by oxidative polymerization, p-PDT₁₄4-E exhibited an elevated highest occupied molecular orbital energy level, facilitating faster hole extraction and enhanced hole conductivity. Additionally, p-PDT₁₄4-E demonstrated an increased glass temperature and a more uniform film morphology. When used as a hole transport material along with the air doping promoter 4-(<i>tert</i>-butyl)pyridinium 1,1,2,2,3,3-hexafluoropropane-1,3-disulfonimide, perovskite solar cells incorporating p-PDT₁₄4-E achieved an average power conversion efficiency (PCE) of 25.5%, surpassing reference cells using spiro-OMeTAD (average PCE of 24.7%) under identical conditions. Furthermore, p-PDT₁₄4-E-based cells exhibited excellent operational stability at 45 °C and thermal storage stability at 85 °C.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"6 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142642632","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":"Engineering Pyreno[1,2-b:8,7-b′]dithiophene-Based Conjugated Polymers for Efficient and Stable Perovskite Solar Cells","authors":"Yaohang Cai,&nbsp;Lifei He,&nbsp;Lingyi Fang,&nbsp;Yuyan Zhang,&nbsp;Jing Zhang,&nbsp;Yi Yuan* and Peng Wang*,&nbsp;","doi":"10.1021/acs.macromol.4c0220610.1021/acs.macromol.4c02206","DOIUrl":"https://doi.org/10.1021/acs.macromol.4c02206https://doi.org/10.1021/acs.macromol.4c02206","url":null,"abstract":"<p >The advancement of p-type conjugated polymers with optimized electrical properties, morphology, and heat tolerance is essential for n-i-p-type perovskite solar cells. Herein, we present a novel conjugated polymer, p-PDT₁₄4-E, composed of alternating units of 4,4,7,7-tetrakis(4-hexylphenyl)-4,7-dihydropyreno[1,2-<i>b</i>:8,7-<i>b</i><i>′</i>]dithiophene (PDT₁₄4) and 3,4-ethylenedioxythiophene. This copolymer was synthesized via a palladium-catalyzed direct arylation polycondensation method. Compared to the corresponding homopolymer p-PDT₁₄4 synthesized by oxidative polymerization, p-PDT₁₄4-E exhibited an elevated highest occupied molecular orbital energy level, facilitating faster hole extraction and enhanced hole conductivity. Additionally, p-PDT₁₄4-E demonstrated an increased glass temperature and a more uniform film morphology. When used as a hole transport material along with the air doping promoter 4-(<i>tert</i>-butyl)pyridinium 1,1,2,2,3,3-hexafluoropropane-1,3-disulfonimide, perovskite solar cells incorporating p-PDT₁₄4-E achieved an average power conversion efficiency (PCE) of 25.5%, surpassing reference cells using spiro-OMeTAD (average PCE of 24.7%) under identical conditions. Furthermore, p-PDT₁₄4-E-based cells exhibited excellent operational stability at 45 °C and thermal storage stability at 85 °C.</p>","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"57 22","pages":"10725–10734 10725–10734"},"PeriodicalIF":5.1,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142713612","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":"Pushing AFM to the Boundaries: Interphase Mechanical Property Measurements near a Rigid Body","authors":"Io Saito, Richard J. Sheridan, Stefan Zauscher, L. Catherine Brinson","doi":"10.1021/acs.macromol.4c01993","DOIUrl":"https://doi.org/10.1021/acs.macromol.4c01993","url":null,"abstract":"Understanding the mechanical properties of polymer nanocomposite materials is essential for industrial use. Particularly, the determination of the polymer modulus at the nanofiller–polymer interphase is important for optimizing the interfacial mechanical properties. Nanoindentation via Atomic Force Microscopy (AFM) is well-established for measuring the modulus of the interphase region with nanoscale spatial resolution. However, indentation into heterogeneous materials presents a confounding issue often referred to as the “substrate effect”, i.e., the structural stress field caused by the rigid body is convoluted with the actual modulus of the interphase region. While finite element analysis (FEA)-based methods can be used to deconvolute the interphase modulus from measured apparent modulus–distance profiles, the experimental validation of this method is still needed. Here, we provide this validation using AFM nanoindentation on a layered model composite that consists of three layers with different moduli to recapitulate the properties of the matrix, the filler, and the interphase of real polymer nanocomposites. By systematically varying the thickness of the “artificial” interphase layer and the AFM probe radius, we obtain modulus–distance profiles over a wide range of indentation conditions. We validate a method to deconvolute the substrate effect using an empirically derived master curve obtained from FEA analysis. Furthermore, we showed that the effect of the artificial interphase on modulus– distance profiles can be distinguished only if the interphase layer is thick enough compared to the contact radius of the probe. Finally, we established an innovative and quantitative framework to predict the interphase thickness from mechanical nanoindentation measurements and discussed the lower, practical limit for interphase thickness determination. In summary, we provide a broadly applicable method to extract interphase mechanical properties of multiphase soft materials and practical guidelines for choosing optimal characterization conditions.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"99 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142642634","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":"The Influence of Graft Rigidity on the Dynamical Behavior of PMMS-Based Polymer Brushes at Ambient and High Pressures","authors":"Sara Zimny,&nbsp;Magdalena Tarnacka*,&nbsp;Paulina Maksym,&nbsp;Żaneta Wojnarowska,&nbsp;Marian Paluch and Kamil Kamiński,&nbsp;","doi":"10.1021/acs.macromol.4c0177910.1021/acs.macromol.4c01779","DOIUrl":"https://doi.org/10.1021/acs.macromol.4c01779https://doi.org/10.1021/acs.macromol.4c01779","url":null,"abstract":"<p >In this paper, we investigated the molecular dynamics of polymer brushes based on poly(mercaptopropyl)methylsiloxane (PMMS), in which the thiol group was grafted with different homologous flexible acrylates (acrylate-based PMMS copolymers) and more rigid methacrylate (methacrylate-based PMMS copolymers) monomers of varying lengths of alkyl chain under ambient and elevated pressure conditions. It was found that the glass transition temperature, <i>T</i>_g, of PMMS homopolymer is significantly lower compared to the other systems. Moreover, surprisingly, in the methacrylate-grafted copolymers, there are two relaxation processes (α and α′), while in the systems grafted with various acrylates, only a single process is present in the supercooled phase. Complementary rheological investigations indicated that the faster α process comes from the segmental motions, while α′ is not detected in the mechanical response. Further high-pressure experiments showed that there is a superposition between segmental and α′ modes irrespective of applied pressure, <i>p</i>, in methacrylate-based PMMS copolymers. This result suggests that the latter process might be considered as a sub-Rouse mode, or alternatively, it may originate from the dielectric active relaxation of the rigid polar side chain (grafts). Moreover, analysis of the high-pressure data allowed us to estimate the pressure coefficient of the glass transition temperature, d<i>T</i>_g/d<i>p</i>, which was much higher for polymer brushes with respect to the PMMS homopolymer. Interestingly, the values of d<i>T</i>_g/d<i>p</i> for methacrylate-grafted copolymers are slightly higher compared to acrylate-based PMMS copolymers, which may be due to the different flexibility/rigidity of both groups of materials as all examined materials have the same degree of polymerization of homopolymer backbone (<i>N</i>_bb ∼ 12) and side chain (<i>N</i>_sc = 1). However, for both groups of studied systems, d<i>T</i>_g/d<i>p</i> values did not scale with chain length. This unexpected result must be related to the structure of the studied grafted copolymers and the character of grafts, derivatives of acrylates/methacrylates. The data presented here extend our knowledge of the influence of the architecture of different molecules on the dynamics of polymers at ambient and high pressures.</p>","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"57 22","pages":"10754–10766 10754–10766"},"PeriodicalIF":5.1,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142719445","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":"Chain Conformation of Polymers Densely Grafted onto Plate-Shaped Particles","authors":"Yusuke Watanabe, Yusuke Kakizawa, Shinya Kato, Sayaka Yamagishi, Naruki Kurokawa, Masatoshi Tokita","doi":"10.1021/acs.macromol.4c01702","DOIUrl":"https://doi.org/10.1021/acs.macromol.4c01702","url":null,"abstract":"Polymer-grafted platelets (PGPLs) were prepared via atom transfer radical polymerization of butyl methacrylate with the initiator bonded to the surface of hematite platelets, and the conformation of the poly(butyl methacrylate) (PBMA) chains grafted onto the top and bottom of the platelets at a dimensionless graft density (σ*) of 0.3–0.9 was studied. PGPLs were shaped into films with platelets parallel to the film surface via dispersion casting followed by hot pressing. The face-to-face distance between platelets increases with the number-average molecular weight of the grafted polymer and equals 2<i>L</i>_cσ*, where <i>L</i>_c is the contour length of the grafted PBMA chains. This suggests that the polymer chains grafted onto a platelet are stretched perpendicular to the platelet face to a similar extent as those grafted onto flat substrates, and their ends are opposed to those grafted from the opposite platelets to fill the space between the platelets.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"98 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142637489","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":"Efficient One-Step Synthesis of Catechol Containing Polymers via Friedel–Crafts Alkylation and Their Use for Water Decontamination","authors":"Timo Sehn, Nicolai Kolb, Alexander Azzawi, Michael A. R. Meier","doi":"10.1021/acs.macromol.4c02233","DOIUrl":"https://doi.org/10.1021/acs.macromol.4c02233","url":null,"abstract":"We herein present an efficient one-step synthesis route toward catechol containing polymers from liquid polybutadiene via a simple post polymerization modification (PPM) approach applying acid catalyzed Friedel–Crafts alkylation (FCA). Accordingly, 100% modification of polybutadiene was achieved within 30 min in bulk at 120 °C. The final structure of the polymer was analyzed by ¹H, ¹³C, 2D nuclear magnetic resonance (NMR), infrared (IR), diffusion ordered spectroscopy (DOSY), and size exclusion chromatography (SEC). Material properties were investigated via thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). Subsequent metal ion removal tests revealed excellent extraction efficiencies (86% ≤ M^<i>n</i>+_removal &lt; 100%) when using the catechol containing polymer as heavy metal sorbent and thus emphasize a potential application for water purification processes.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"30 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142642639","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}