Macromolecules最新文献_第7页

Cis / Trans Configuration-Tuned Crystallization and Mechanical Properties in Aliphatic Polyesters Synthesized from C4 Diacids and α , ω -Diols C4二酸与α， ω -二醇合成脂肪族聚酯的顺/反式调构结晶及力学性能

IF 5.5 1区化学

Macromolecules Pub Date : 2026-10-13 DOI: 10.1021/acs.macromol.6c01909

Xuekuan Ma,Ying Zheng,Maolin Li,Xing Zhang,Junfeng Liu,Chengtao Yu,Guorong Shan,Yongzhong Bao,Pengju Pan

{"title":"Cis\u0000 /\u0000 Trans\u0000 Configuration-Tuned Crystallization and Mechanical Properties in Aliphatic Polyesters Synthesized from C4 Diacids and\u0000 \u0000 α\u0000 ,\u0000 ω\u0000 \u0000 -Diols","authors":"Xuekuan Ma,Ying Zheng,Maolin Li,Xing Zhang,Junfeng Liu,Chengtao Yu,Guorong Shan,Yongzhong Bao,Pengju Pan","doi":"10.1021/acs.macromol.6c01909","DOIUrl":"https://doi.org/10.1021/acs.macromol.6c01909","url":null,"abstract":"Abstract Main-chain C═C units provide an effective structural handle for tailoring the physical structure and macroscopic property of polymers. However, how the cis/trans configuration of main-chain C═C units impacts the crystallization and physical property of polyesters is not well understood. Herein, we synthesized a series of saturated and cis/trans-unsaturated aliphatic polyesters from the four-carbon (C4) diacids (succinic acid, fumaric acid, or maleic acid) with even-numbered α,ω-diols (nCH2 = 4–14), and investigated their crystallizability, crystal polymorphism, mechanical properties, and chemical recycling. We find that the saturated and trans-polyesters with nCH2 = 4–14 all exhibit good crystallizability, while the cis-polyesters crystallize only when the CH2 spacer is sufficiently long. Compared with the saturated analogs, trans-C═C units can enhance the crystallization and melting temperatures (Tc, Tm) of polyesters. Interestingly, the long-spaced cis-polyesters (nCH2 = 12, 14) show the Tc dependence of crystal polymorphism, forming the metastable hexagonal form II at a low Tc and the thermodynamically stable form I at a high Tc. Mechanical properties of polyesters are highly influenced by the cis/trans-C═C configuration, and the cis-polyesters have much weakened mechanical strength and modulus than the trans and saturated ones. Moreover, these polyesters can be chemically recycled by methanolysis and repolymerization while preserving the C═C configuration in the recycling process. This study has shed light on the critical role of main-chain cis/trans-C═C configuration in regulating the crystallization and mechanical properties of aliphatic polyesters.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"39 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149209872","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}

引用次数: 0

Lithium Ion Responsive [2]Catenane Molecular Spring 锂离子响应[2]链烷分子弹簧

IF 5.7 1区化学

Macromolecules Pub Date : 2026-10-13 Epub Date: 2026-08-01 DOI: 10.1021/acs.macromol.6c00949

Xingang Tan, Yi Shi, Yuru Hao, Yutong Xie, Yixuan Zhang, Kaiya Wang, Xiao-Yu Hu

{"title":"Lithium Ion Responsive [2]Catenane Molecular Spring","authors":"Xingang Tan, Yi Shi, Yuru Hao, Yutong Xie, Yixuan Zhang, Kaiya Wang, Xiao-Yu Hu","doi":"10.1021/acs.macromol.6c00949","DOIUrl":"10.1021/acs.macromol.6c00949","url":null,"abstract":"Catenanes, which can be designedas stimulus-responsive molecularmachines with controlled motion, hold significant potential for biomimeticand molecular switching applications. However, the synthesis of structurallyintricate and multifunctional catenanes remains challenging. Herein,we report the construction of an elaborate molecular machine thatintegrates a supramolecular macrocycle, pillararene, into a catenaneframework. This system exhibits both intramolecular charge transfer(CT) and photoinduced electron transfer (PET), both of which can generatenaphthalenediimide radical anions (NDI•–).In terms of ion recognition, the supramolecular system exhibits highspecificity toward lithium ions. Coordination with Li+ inducesa contracted conformational state of the catenane, whereas subsequentextraction of Li+ by the chelator 12-crown-4 restores itsrelaxed conformational state. Through alternating cycles of addingLi+ and 12-crown-4, reversible contraction–relaxationmotion of this so-called “molecular spring” (in a metaphoricalsense) is achieved, demonstrating a switchable conformational transition.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"59 19","pages":"10903–10910"},"PeriodicalIF":5.7,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148665825","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}

引用次数: 0

Inverse Vulcanized Polysulfide-Mediated Efficient Crosslinking of Epoxy Elastomers: Mechanism and Recyclability 反硫化聚硫化物介导的环氧弹性体高效交联：机理和可回收性

IF 5.7 1区化学

Macromolecules Pub Date : 2026-10-13 Epub Date: 2026-09-15 DOI: 10.1021/acs.macromol.6c01888

Qiang Fu, Dong Wang, Baochun Guo, Zhenghai Tang

{"title":"Inverse Vulcanized Polysulfide-Mediated Efficient Crosslinking of Epoxy Elastomers: Mechanism and Recyclability","authors":"Qiang Fu, Dong Wang, Baochun Guo, Zhenghai Tang","doi":"10.1021/acs.macromol.6c01888","DOIUrl":"10.1021/acs.macromol.6c01888","url":null,"abstract":"Incorporating dynamic covalent bonds into epoxy thermosets offers a promising route to confer recyclability, yet the development of efficient and scalable strategies for constructing dynamic epoxy networks remains challenging. Herein, an inverse vulcanized polysulfide (SP), synthesized from elemental sulfur and styrene, was directly employed as a crosslinker and a dynamic S–S bond reservoir for an epoxy-based elastomer ethylene-vinyl acetate-glycidyl methacrylate terpolymer. The polysulfide bonds in SP are subjected to heterolytic cleavage via nucleophilic activation by 1,2-dimethylimidazole, producing thiolate species that subsequently couple with epoxy groups, thereby constructing a crosslinked network comprising dynamic disulfide and polysulfide motifs. The crosslinking mechanism was verified by model reactions and density functional theory calculations. Moreover, the crosslinking density and network structure of the resulting elastomers can be regulated by varying the SP content, leading to tunable thermomechanical properties and dynamic behaviors. Additionally, dynamic S–S metathesis endows the crosslinked elastomer with topological rearrangement, thereby conferring reprocessability. The recycled elastomer retains a high recovery efficiency of mechanical properties. This work provides a facile and sustainable strategy for constructing recyclable epoxy elastomers and expands the application potential of inverse vulcanized polysulfides in dynamic epoxy thermosets.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"59 19","pages":"10817–10824"},"PeriodicalIF":5.7,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148974095","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}

引用次数: 0

Impact of Precision Sequence on Microphase Separation of Graft Copolymers Bearing Immiscible Polymer Chains: Alternating versus Random Architectures 精密序列对含非混相聚合物链接枝共聚物微相分离的影响：交替与随机结构

IF 5.7 1区化学

Macromolecules Pub Date : 2026-10-13 Epub Date: 2026-09-16 DOI: 10.1021/acs.macromol.6c01246

Aoto Ishikawa, Ryota Uehara, Teruaki Hayakawa, Makoto Ouchi

{"title":"Impact of Precision Sequence on Microphase Separation of Graft Copolymers Bearing Immiscible Polymer Chains: Alternating versus Random Architectures","authors":"Aoto Ishikawa, Ryota Uehara, Teruaki Hayakawa, Makoto Ouchi","doi":"10.1021/acs.macromol.6c01246","DOIUrl":"10.1021/acs.macromol.6c01246","url":null,"abstract":"Graft alternating copolymers bearing polystyrene (PS) and polylactide (PLA) graft chains were precisely synthesized via selective cyclopolymerization of a pendant-transformable divinyl monomer followed by postpolymerization modification for chain incorporation via a grafting-to and grafting-from approach. The number-averaged polymerization degrees (DPn’s) of both the backbone and graft chains were precisely controlled. Importantly, the corresponding graft “random” copolymers as well as the PS-PLA block copolymers of identical DPn’s were also synthesized to enable direct comparison of their microphase separation behaviors. The graft alternating copolymers with a volume fraction of approximately 5:5 exhibited periodic scattering peaks attributable to a lamellar morphology in the SAXS profile. These peaks of the graft alternating copolymers were significantly sharper than those observed for the random and block architectures, and the domain spacing was smaller than those observed for the random architectures. This trend became even more pronounced at a volume fraction of approximately 7:3, where a cylindrical morphology was formed.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"59 19","pages":"11105–11114"},"PeriodicalIF":5.7,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148974102","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}

引用次数: 0

Sequence-Dependent Mesophase Cascades in Dual-Responsive Polymeric Micelles 双响应聚合物胶束中序列依赖的中间相级联

IF 5.7 1区化学

Macromolecules Pub Date : 2026-10-13 Epub Date: 2026-09-17 DOI: 10.1021/acs.macromol.6c01668

Michal Brodsky, Nicole Edelstein-Pardo, Avichai Srebrnik-Gabbay, Olga Shamis, Michael Gozin, Roey J. Amir

{"title":"Sequence-Dependent Mesophase Cascades in Dual-Responsive Polymeric Micelles","authors":"Michal Brodsky, Nicole Edelstein-Pardo, Avichai Srebrnik-Gabbay, Olga Shamis, Michael Gozin, Roey J. Amir","doi":"10.1021/acs.macromol.6c01668","DOIUrl":"10.1021/acs.macromol.6c01668","url":null,"abstract":"Stimuli-responsive polymeric assemblies capable of undergoing controlled structural transformations offer powerful opportunities for the design of advanced functional materials. Here, we report a modular strategy for programming sequence-dependent mesophase transitions in polymeric micellar formulations through the co-assembly of diblock and triblock amphiphiles bearing orthogonally responsive end-groups. By combining amphiphiles with distinct molecular architectures and pH- and enzyme-responsive functionalities, we generated mixed micellar systems that undergo an initial mesophase transition from micelles to a hydrogel upon exposure to acidic conditions, followed by a subsequent enzyme-triggered transformation into soluble polymers. Importantly, reversing the order of introducing the stimuli resulted in an alternative multistep response pathway, in which selective enzymatic degradation of the triblock amphiphiles produces diblock-based micelles that, upon lowering the pH, subsequently undergo acid-induced hydrolysis into soluble polymer chains. These findings demonstrate that both the composition of the co-assembled amphiphiles and the sequence of external stimuli dictate the resulting transformation pathway and kinetics. Overall, this work establishes a general approach for designing programmable multi-responsive polymeric formulations that exhibit cascade mesophase transitions through the mixing of amphiphiles with orthogonal reactivities. Such systems provide a promising platform for the development of advanced delivery systems, including orally administered formulations that transition from circulating micelles to hydrogel drug depots and ultimately degrade into readily cleared soluble polymers.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"59 19","pages":"10794–10805"},"PeriodicalIF":5.7,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148985078","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}

引用次数: 0

Quantum Dot-Induced Kinetic Bottleneck in Singlet Exciton Relaxation of Conjugated Polymer Aggregates 共轭聚合物聚集体单线态激子弛豫的量子点诱导动力学瓶颈

IF 5.7 1区化学

Macromolecules Pub Date : 2026-10-13 Epub Date: 2026-09-19 DOI: 10.1021/acs.macromol.6c01207

Yeon Gyu Kim, Se Gyo Han, Minyoung Jeong, Taeyong Ha, Dong Hyeon Kim, Hyunjin Cho, Gui-Min Kim, Sein Chung, Hyuk Gu Yun, Kyeong-Hyeon Lee, Jun Sang Cho, Tae Rim Ko, Kyu Young Kim, Jieun Bang, Jaekak Yoo, Jungho Mun, Junsuk Rho, Seung Mi Lee, JaeHong Park, Young Jin Choi, Boseok Kang, Joon I. Jang, Doh C. Lee, Mun Seok Jeong, Sungjee Kim, Kilwon Cho, Dongki Lee

{"title":"Quantum Dot-Induced Kinetic Bottleneck in Singlet Exciton Relaxation of Conjugated Polymer Aggregates","authors":"Yeon Gyu Kim, Se Gyo Han, Minyoung Jeong, Taeyong Ha, Dong Hyeon Kim, Hyunjin Cho, Gui-Min Kim, Sein Chung, Hyuk Gu Yun, Kyeong-Hyeon Lee, Jun Sang Cho, Tae Rim Ko, Kyu Young Kim, Jieun Bang, Jaekak Yoo, Jungho Mun, Junsuk Rho, Seung Mi Lee, JaeHong Park, Young Jin Choi, Boseok Kang, Joon I. Jang, Doh C. Lee, Mun Seok Jeong, Sungjee Kim, Kilwon Cho, Dongki Lee","doi":"10.1021/acs.macromol.6c01207","DOIUrl":"10.1021/acs.macromol.6c01207","url":null,"abstract":"We designed hybrid aggregate model systems with cascade energy alignment from conjugated polymers (CPs) to quantum dots (QDs) to investigate the effects of QDs on CP singlet (S1) excitons. Radiative recombination of S1 excitons occurs within 1 ps in the chlorinated CP/QD hybrid system, indicating an enhanced emissive pathway in an early-time regime. Optimized CP/QD phase separation induces end-on chain orientation and strengthens intrachain excitonic coupling, generating a vertical driving force for intrachain-mediated S1 dissociation along the z-axis. This force interacts with a lateral driving force in the xy-plane—stemming from the conduction-band offset—that biases CP electron density toward QD domains. The interplay between the two forces introduces a kinetic bottleneck that delays exciton relaxation and polaron formation, thereby increasing the probability of radiative recombination and the photoluminescence quantum yield. Our findings provide a strategy to regulate exciton decay pathways and improve CP-based device efficiency.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"59 19","pages":"11137–11148"},"PeriodicalIF":5.7,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149003527","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}

引用次数: 0

Melts of Brush Copolymers: From Microphase Separation to Liquid-Crystalline Order 电刷共聚物熔体：从微相分离到液晶顺序

IF 5.7 1区化学

Macromolecules Pub Date : 2026-10-13 Epub Date: 2026-09-24 DOI: 10.1021/acs.macromol.6c01222

Zilu Wang, Edward T. Samulski, Sergei S. Sheiko, Andrey V. Dobrynin

{"title":"Melts of Brush Copolymers: From Microphase Separation to Liquid-Crystalline Order","authors":"Zilu Wang, Edward T. Samulski, Sergei S. Sheiko, Andrey V. Dobrynin","doi":"10.1021/acs.macromol.6c01222","DOIUrl":"10.1021/acs.macromol.6c01222","url":null,"abstract":"We use coarse-grained molecular dynamics simulations to investigate structural organization in melts of brush copolymers as a function of side-chain grafting density, backbone-side-chain miscibility, and backbone rigidity. At low grafting densities, decreasing miscibility drives microphase separation of backbones and side chains and leads to the formation of multi-backbone domains whose morphology evolves from cylindrical aggregates to lamellar structures as the spacer length between grafting points increases. In this regime, the characteristic wavevector q* corresponding to the peak position in the structure factor decreases with increasing the spacer length, reflecting an increase in the domain size. For semiflexible backbones, microphase separation is accompanied by mutual backbone alignment within the multi-backbone domains. Graft copolymers with miscible rigid backbones and flexible side chains can also undergo microphase separation. In this case, the morphological transformations are entropic in origin and are forced by local packing constraints imposed by the flexibility of backbones and side chains and can be viewed as an emergence of local nematic-like ordering of the backbones in a “solvent” of side chains. At high grafting densities, where multiple side chains are attached to each backbone bead, the backbones become effectively screened by the side chains and the melts display smectic-like organization. In this regime, the structure factor develops higher-order peaks at integer multiples of q*. Analysis of orientational correlations of side chain end-to-end vectors confirms that this ordering corresponds to appearance of layers of oriented side chains separating brush backbones. These results establish how graft copolymer architecture, intermolecular interactions, and backbone rigidity govern the transition from microphase-separated comb-like melts to smectic-like ordering in bottlebrush systems.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"59 19","pages":"11247–11258"},"PeriodicalIF":5.7,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149049575","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}

引用次数: 0

Effect of Block Copolymer Composition and Architecture on Phase Separation and Thermomechanical Properties of Epoxy Composites 嵌段共聚物组成及体系结构对环氧复合材料相分离及热机械性能的影响

IF 5.7 1区化学

Macromolecules Pub Date : 2026-10-13 Epub Date: 2026-09-26 DOI: 10.1021/acs.macromol.6c01618

Tanner L. Grover, Jennafer M. Davis, Lars Nelson, Douglas R. Tree, C. Allan Guymon

{"title":"Effect of Block Copolymer Composition and Architecture on Phase Separation and Thermomechanical Properties of Epoxy Composites","authors":"Tanner L. Grover, Jennafer M. Davis, Lars Nelson, Douglas R. Tree, C. Allan Guymon","doi":"10.1021/acs.macromol.6c01618","DOIUrl":"10.1021/acs.macromol.6c01618","url":null,"abstract":"Inducing phase separation in crosslinked polymer systems with high-molecular-weight block copolymers (BCP) has been shown to produce composites with enhanced tensile properties and unique thermomechanical behavior. However, detailed understanding of the relationships between BCP chemical composition and physical interactions within the polymerizing matrix is limited. In this work, amphiphilic reactive BCPs were synthesized and incorporated into a cationic photopolymerizable epoxy resin to study the effect of BCP architecture on phase-separated structure and bulk material properties. We prepared the BCPs using photoiniferter polymerization to control and vary block chemical composition, block volume fraction, and hydroxyl functionality of poly(methyl acrylate-block-hydroxyethyl acrylate) (PMA-b-PHEA) and poly(butyl acrylate-block-hydroxyethyl acrylate) (PBA-b-PHEA) copolymers. Self-consistent field theory simulations predicted, and AFM measurements confirmed, that the PMA-based BCPs had smaller domain sizes upon microphase separation—a result of the greater miscibility between the PMA and PHEA blocks—leading to a 200% increase in the tensile strength and material toughness compared to the PBA-based system. Furthermore, the extent of phase separation (and thus the thermomechanical properties) could be controlled by varying the relative MA/BA composition in the nonreactive BCP segment. Additionally, we varied the density of OH pendant groups to investigate the role of hydrogen bonding and network connectivity on resin rheology, microstructure, and cured mechanical properties. This work provides structure–property relationships and links BCP composition to phase-separated structure for improving properties of photocured materials.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"59 19","pages":"11184–11196"},"PeriodicalIF":5.7,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149049762","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}

引用次数: 0

Mechanistic Origin of Compressed Exponential Time Dependence in Block Copolymer Micelle Fragmentation 嵌段共聚物胶束破碎中压缩指数时间依赖性的机理起源

IF 5.7 1区化学

Macromolecules Pub Date : 2026-10-13 Epub Date: 2026-09-25 DOI: 10.1021/acs.macromol.6c01373

Yash Nandola, Supriya Gupta, Andrew J. Spakowitz, Kevin D. Dorfman, Timothy P. Lodge

{"title":"Mechanistic Origin of Compressed Exponential Time Dependence in Block Copolymer Micelle Fragmentation","authors":"Yash Nandola, Supriya Gupta, Andrew J. Spakowitz, Kevin D. Dorfman, Timothy P. Lodge","doi":"10.1021/acs.macromol.6c01373","DOIUrl":"10.1021/acs.macromol.6c01373","url":null,"abstract":"Multiple studies of block copolymer micelle fragmentation have revealed a surprising compressed exponential time dependence of relaxation toward the equilibrium size, following exp[(–t/τ)n], with n ≈ 2. We present a simple two-step kinetic model that quantitatively explains the mechanistic origin of the apparent compressed exponential behavior. In this model, as-prepared micelles evolve toward steady-state micelles via metastable, “peanut-shaped” intermediates. Concentrations of the three states are obtained as a function of time by coupling simple rate laws. The initial and final sizes are known from experiments. The size of the intermediates is estimated by modelling them as prolate ellipsoids, leading to a radius about 2% larger than that of the as-prepared micelles. The two rate constants, k1 and k2, for the formation and decomposition of the intermediate state, respectively, are estimated by fitting experimental data, while providing the sizes of the three states as input. Fitting reveals that k1 and k2 need to be very similar (within a factor of about 2) to observe the apparent compressed exponential dynamics. Equivalent magnitudes of k1 and k2 suggest that the intermediate state is metastable with a finite lifetime and not a transition state, an inference that is supported by the appearance of the peanut-shaped intermediates in previously conducted in-situ TEM experiments. Calculations also indicate that the relative population of the intermediate state reaches a peak value of 20–40%, which should facilitate further imaging of intermediates via TEM. We are not aware of a current theory for block copolymer micelle fragmentation that proposes passage through a metastable intermediate, so this question certainly merits further examination.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"59 19","pages":"10883–10891"},"PeriodicalIF":5.7,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149049799","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}

引用次数: 0

Solvent-Induced Crystallization of Semiaromatic Poly(ester imide)s 半芳香族聚酰亚胺酯的溶剂诱导结晶

IF 5.7 1区化学

Macromolecules Pub Date : 2026-10-13 Epub Date: 2026-09-24 DOI: 10.1021/acs.macromol.6c01297

Zidong He, Xiangqi Meng, Liang Wu, Ruibin Wang, Gangsheng Tong, Chongyin Zhang, Dali Wang, Yongqing Li, Xinyuan Zhu

{"title":"Solvent-Induced Crystallization of Semiaromatic Poly(ester imide)s","authors":"Zidong He, Xiangqi Meng, Liang Wu, Ruibin Wang, Gangsheng Tong, Chongyin Zhang, Dali Wang, Yongqing Li, Xinyuan Zhu","doi":"10.1021/acs.macromol.6c01297","DOIUrl":"10.1021/acs.macromol.6c01297","url":null,"abstract":"Solvent selection and the chain packing behavior in solution are crucial to the solution processing and material performance of poly(ester imide)s (PEIs). In this work, it was found that specific semiaromatic PEIs can undergo an amorphous-to-crystalline transition in polar solvents, exhibiting typical solvent-induced crystallization behavior. The effects of temperature, concentration, solvent type, and aliphatic chain structure on this crystallization behavior were systematically investigated. Combined with kinetic studies and solid-state nuclear magnetic resonance (NMR) techniques, as well as molecular dynamics simulations, the crystallization mechanism was elucidated, and the solvent-induced crystallization behavior of PEIs was summarized. Additionally, the effects of structural differences among PEI homologues on the morphology of their crystalline products were also investigated. The results demonstrated that the synergistic interplay between the unsymmetric planar structure and the aliphatic chains in semiaromatic PEIs is key to inducing this solvent-induced crystallization behavior. This work not only offers guidance for solvent selection and morphology design in PEI solution processing, but also serves as a valuable reference for PEI material design. In addition, the unusual crystallization behavior provides an alternative perspective for understanding polymer crystallization.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"59 19","pages":"11033–11043"},"PeriodicalIF":5.7,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149049801","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}

引用次数: 0