ACS Macro Letters最新文献

Hydration Effects Driving Network Remodeling in Hydrogels during Cyclic Loading

IF 5.8

ACS Macro Letters Pub Date : 2025-01-27 DOI: 10.1021/acsmacrolett.4c00653

Baptiste Le Roi, Joshua M. Grolman

引用次数: 0

Understanding the Topology Freezing Temperature of Vitrimer-Like Materials through Complementary Structural and Rheological Analyses for Phase-Separated Network

IF 5.8

ACS Macro Letters Pub Date : 2025-01-27 DOI: 10.1021/acsmacrolett.4c00783

Mikihiro Hayashi, Maho Suzuki, Takumi Kito

{"title":"Understanding the Topology Freezing Temperature of Vitrimer-Like Materials through Complementary Structural and Rheological Analyses for Phase-Separated Network","authors":"Mikihiro Hayashi, Maho Suzuki, Takumi Kito","doi":"10.1021/acsmacrolett.4c00783","DOIUrl":"https://doi.org/10.1021/acsmacrolett.4c00783","url":null,"abstract":"Vitrimers are sustainable cross-linked polymers characterized by an associative bond exchange mechanism within their network. A well-known feature of vitrimers is the Arrhenius dependence of the viscosity or relaxation time. Another important aspect is the existence of a topology-freezing temperature (Tv), which represents a transition between the viscoelastic solid state and the malleable viscoelastic liquid state. Various methods, including viscosity-temperature plots and temperature-ramp creep (or dilatometry), have been proposed for determining the Tv. In this study, we complementarily employ X-ray scattering-based structural analysis and rheological analysis to assign Tv in phase-separated vitrimer-like materials undergoing trans-N-alkylation bond exchange. Note that the trans-N-alkylation progresses via the dissociative bond exchange pathway, whereas our previous studies demonstrated that the temperature-dependence of relaxation time followed the Arrhenius dependence, which was the reason for the classification as a vitrimer-like material. Specifically, we identify Tv as the temperature at which an anomalous increase in domain distance occurs during the rubbery state in the structural analysis. In the rheological analysis, Tv corresponds to the transition temperature marking the shift from the Williams–Landel–Ferry dependence to the Arrhenius dependence in the shift factors used to create master curves for frequency sweep rheology data. Importantly, both methods yield nearly the same Tv, validating the accuracy of the proposed assignment and, thus, providing valuable insights into the specific properties of vitrimers.","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":"39 1","pages":""},"PeriodicalIF":5.8,"publicationDate":"2025-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143050491","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Light-Induced Transformation from Covalent to Supramolecular Polymer Networks

IF 5.8

ACS Macro Letters Pub Date : 2025-01-26 DOI: 10.1021/acsmacrolett.4c00744

Chuan Yue, Jingxi Deng, Bo Pang, Guoquan Liu, Yuanhao Wang, Haonan Xu, Shaolei Qu, Yuhang Liu, Yanxi Liu, Zhaoming Zhang, Hui Zhou, Xuzhou Yan

{"title":"Light-Induced Transformation from Covalent to Supramolecular Polymer Networks","authors":"Chuan Yue, Jingxi Deng, Bo Pang, Guoquan Liu, Yuanhao Wang, Haonan Xu, Shaolei Qu, Yuhang Liu, Yanxi Liu, Zhaoming Zhang, Hui Zhou, Xuzhou Yan","doi":"10.1021/acsmacrolett.4c00744","DOIUrl":"https://doi.org/10.1021/acsmacrolett.4c00744","url":null,"abstract":"Stimuli-responsive polymers have demonstrated significant potential in the development of smart materials due to their capacity to undergo targeted property changes in response to external physical or chemical stimuli. However, the scales of response in most existing stimuli-responsive polymer systems are mainly focused on three levels: functional units, chain conformations, or polymer topologies. Herein, we have developed a covalent polymer network (CPN) capable of converting into a supramolecular polymer network (SPN) within bulk materials directly at the scale of polymer network types. This transformation is enabled by specifically designed covalent moieties that upon UV exposure reveal quadruple hydrogen bonding sites, allowing the formation of a supramolecular network. This network-type transition from CPN to SPN induces pronounced intrinsic changes in material properties, including a substantially increased breaking elongation, lower Young’s modulus, reduced fracture strength, and decreased creep resistance, marking a shift from a stable, rigid structure to a dynamic, adaptable one. These findings provide new insights into the design of advanced stimuli-responsive polymer materials through network-type transformations, opening new avenues for applications in smart and multifunctional materials.","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":"4 1","pages":""},"PeriodicalIF":5.8,"publicationDate":"2025-01-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143044388","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Water Droplet Templating Technique to Design Three-Dimensionally Ordered Porous Structures of Polymer Film

IF 5.8

ACS Macro Letters Pub Date : 2025-01-24 DOI: 10.1021/acsmacrolett.4c00753

Wanxin Peng, Sen Lin, Feng Yang, Ya Cao, Ming Xiang, Tong Wu

{"title":"Water Droplet Templating Technique to Design Three-Dimensionally Ordered Porous Structures of Polymer Film","authors":"Wanxin Peng, Sen Lin, Feng Yang, Ya Cao, Ming Xiang, Tong Wu","doi":"10.1021/acsmacrolett.4c00753","DOIUrl":"https://doi.org/10.1021/acsmacrolett.4c00753","url":null,"abstract":"We developed a unique water droplet templating method to fabricate polymer films with three-dimensionally ordered porous structures. This technique is based on a polymer/solvent/H2O ternary system, and the key is to choose a volatile and hydrophobic solvent that is slightly miscible with H2O. With the fast evaporation of the solvent, water droplets separate from the casting solution and condense from the air to act as pore templates inside the film and on the surface, respectively. According to this law, nitrocellulose (NC) films were produced from the NC/methyl acetate (MA)/H2O system in which the solubility of H2O in MA is 8.1 wt %. By modulating the solution concentration (density) from 3% to 9% NC, the distribution of separated water droplets (pores) in the solution can be flexibly controlled from sinking to floating. On the other hand, substantial ordered honeycomb pores, originated from condensed water droplets, distribute uniformly on the surface of NC films. This water droplet templating technique can be extensively applied in various polymer films, providing an effective pathway to designing polymer films with a desirable porous structure and diverse functionalities.","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":"108 1","pages":""},"PeriodicalIF":5.8,"publicationDate":"2025-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143027027","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","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 Liquid Crystalline Ordering of Gapped DNA 间隙DNA的序列依赖液晶排序

IF 5.8

ACS Macro Letters Pub Date : 2025-01-22 DOI: 10.1021/acsmacrolett.4c00788

Sineth G. Kodikara, James T. Gleeson, Antal Jakli, Samuel Sprunt, Hamza Balci

引用次数: 0

A Pseudo-Block Copolymerization Access to Cyclic Alternating Copolymers through Segment-Selective Transesterification 通过段选择性酯交换反应获得环交替共聚物的伪嵌段共聚

IF 5.8

ACS Macro Letters Pub Date : 2025-01-21 DOI: 10.1021/acsmacrolett.4c00772

Hongxuan Zhu, Fengzhuang Liu, Hongxin Zhang, Junpeng Zhao

{"title":"A Pseudo-Block Copolymerization Access to Cyclic Alternating Copolymers through Segment-Selective Transesterification","authors":"Hongxuan Zhu, Fengzhuang Liu, Hongxin Zhang, Junpeng Zhao","doi":"10.1021/acsmacrolett.4c00772","DOIUrl":"https://doi.org/10.1021/acsmacrolett.4c00772","url":null,"abstract":"Efficient synthesis of cyclic polymers remains a frontier challenge. We report here that macromolecular transesterification during a pseudoblock copolymerization process can be utilized for such a purpose. Organobase-catalyzed ring-opening alternating copolymerization of 3,4-dihydrocoumarin and epoxide is conducted with four-armed poly(ethylene oxide) (PEO) as a macroinitiator. Intramolecular transesterification (backbiting) occurs selectively on the newly formed polyester segments. The disconnected cyclic alternating copolymers can be easily isolated by precipitation owing to their substantial solubility difference from the PEO-containing acyclic parts. The obtained cyclic alternating copolymers exhibit low dispersity (<1.2) and a molar mass of around 3 kg mol–1, irrespective of the monomer-to-initiator feed ratio, indicating thermodynamic control over the ring size. The macrocyclic structure is confirmed by both mass spectroscopy and microscopic visualization and then utilized to prepare cyclic-brush terpolymer by thiol–ene modification, followed by graft polymerization of propylene oxide.","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":"45 1","pages":""},"PeriodicalIF":5.8,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142992593","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Reversible Thixotropic Rheological Properties of Graphene-Incorporated Epoxy Inks for Self-Standing 3D Printing 石墨烯环氧树脂墨水的可逆触变流变特性

IF 5.8

ACS Macro Letters Pub Date : 2025-01-12 DOI: 10.1021/acsmacrolett.4c00765

Hanna Sun, Uiseok Hwang, Soochan Kim, Jaeuk Sung, Taesung Kim, Jonghwan Suhr, In-Kyung Park, Jae-Do Nam

{"title":"Reversible Thixotropic Rheological Properties of Graphene-Incorporated Epoxy Inks for Self-Standing 3D Printing","authors":"Hanna Sun, Uiseok Hwang, Soochan Kim, Jaeuk Sung, Taesung Kim, Jonghwan Suhr, In-Kyung Park, Jae-Do Nam","doi":"10.1021/acsmacrolett.4c00765","DOIUrl":"https://doi.org/10.1021/acsmacrolett.4c00765","url":null,"abstract":"As three-dimensional (3D) printing has emerged as a new manufacturing technology, the demand for high-performance 3D printable materials has increased to ensure broad applicability in various load-bearing structures. In particular, the thixotropic properties of materials, which allow them to flow under applied external forces but resist flowing otherwise, have been reported to enable rapid and high-resolution printing owing to their self-standing and easily processable characteristics. In this context, graphene nanosheets exhibit unique π–π stacking interactions between neighboring sheets, likely imparting self-standing capability to low-viscosity inks. Herein, we develop a thermally curable graphene-incorporated epoxy ink system that exhibits shear-thinning characteristics and upright standing capability owing to its high static yield stress (∼1,680 Pa). The reversible liquid-to-solid phase transition of the composite ink, absent in the pristine epoxy ink, is clearly identified by its viscoelastic properties and dynamic yield stress. This thixotropic composite ink enables the continuous filament printing of 10 stacked layers without the spreading of injected filaments. Significantly, the 3D-printed composite structure, post-thermal curing, exhibits robust structural integrity and is free from weld lines or voids at the stacked interfaces. Combined with the clearly elucidated processing–structure–property relationships of the ink system, our results highlight its potential for a wide spectrum of applications.","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":"29 1","pages":""},"PeriodicalIF":5.8,"publicationDate":"2025-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142968374","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Strategy for Fabricating Multiple-Shape Memory Polymeric Materials Based on Solid State Mixing 基于固态混合的多形状记忆聚合物材料制备策略

IF 5.8

ACS Macro Letters Pub Date : 2025-01-12 DOI: 10.1021/acsmacrolett.4c00601

Salim-Ramy Merouani, Roman Kulagin, Vladislav Bondarenko, Ramin Hosseinnezhad, Fahmi Zaïri, Iurii Vozniak

{"title":"Strategy for Fabricating Multiple-Shape Memory Polymeric Materials Based on Solid State Mixing","authors":"Salim-Ramy Merouani, Roman Kulagin, Vladislav Bondarenko, Ramin Hosseinnezhad, Fahmi Zaïri, Iurii Vozniak","doi":"10.1021/acsmacrolett.4c00601","DOIUrl":"https://doi.org/10.1021/acsmacrolett.4c00601","url":null,"abstract":"Traditionally, multiple shape memory polymers (multiple-SMPs) are created by forming either immiscible blends with high phase continuity (cocontinuous or multilayer phase morphology) or miscible blends that exhibit compositional heterogeneity at the nanoscale. Here, a new strategy for the fabrication of multiple-SMPs is proposed. It consists of the possibility of homogeneous mixing of immiscible polymers in the solid state under high pressure and shear deformation conditions. The blends formed in this way exhibit homogeneity of mixing down to the nanoscale, up to 40–95 nm. The transition from immiscible to miscible blends leads to an improvement not only in shape memory but also in the mechanical performance of the blends formed. Polypropylene (PP) and polystyrene (PS) were selected as pairs of immiscible polymers. The method of solid phase mixing is high pressure torsion (HPT). It was shown that the HPT-processed 50% PP/50% PS blend is able to exhibit an excellent triple shape memory effect (shape fixation of ∼94–95%, and recovery of ∼85–95%) with widely tunable (low and high) transition temperatures.","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":"26 1","pages":""},"PeriodicalIF":5.8,"publicationDate":"2025-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142962679","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Construction of Supramolecular Polymer Network Elastomers Based on Pillar[5]arene/Alkyl Chain Host–Guest Interactions 基于柱状[5]芳烃/烷基链主客体相互作用的超分子聚合物网络弹性体的构建

IF 5.8

ACS Macro Letters Pub Date : 2025-01-11 DOI: 10.1021/acsmacrolett.4c00826

Qingyun Li, Kai Hu, Shaoyu Xu, Xiaofan Ji

{"title":"Construction of Supramolecular Polymer Network Elastomers Based on Pillar[5]arene/Alkyl Chain Host–Guest Interactions","authors":"Qingyun Li, Kai Hu, Shaoyu Xu, Xiaofan Ji","doi":"10.1021/acsmacrolett.4c00826","DOIUrl":"https://doi.org/10.1021/acsmacrolett.4c00826","url":null,"abstract":"As a special kind of supramolecular compound with many favorable properties, pillar[n]arene-based supramolecular polymer networks (SPNs) show potential application in many fields. Although we have come a long way using pillar[n]arene to prepare SPNs and construct a series of smart materials, it remains a challenge to enhance the mechanical strength of pillar[n]arene-based SPNs. To address this issue, a new supramolecular regulation strategy was developed, which could precisely control the preparation of pillar[n]arene-based SPN materials with excellent mechanical properties by adjusting the polymer network structures. Specifically, we utilized the host–guest interaction between pillar[5]arene and the alkyl chain of butyl acrylate monomer to form a supramolecular polymer network and achieved the transformation of different states by regulating the cross-linking density of the polymer networks. Additionally, the polymer networks exhibited good stimuli responsiveness as well as excellent dynamic properties and reconfigurable characteristics through a temperature change and the addition of competitive hosts or guests. The research provided new possibilities for the development of polymer materials.","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":"16 1","pages":""},"PeriodicalIF":5.8,"publicationDate":"2025-01-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142961214","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Microcapsule-Containing Self-Reporting Materials Based on Donor–acceptor Stenhouse Adducts 基于施-受体斯坦豪斯加合物的微胶囊自报告材料

IF 5.8

ACS Macro Letters Pub Date : 2025-01-10 DOI: 10.1021/acsmacrolett.4c00715

Qinguan Zhang, Yaning He

引用次数: 0