Macromolecules最新文献

{"title":"Isomer-Free Synthesis of Silicone Polyethers","authors":"Ryan B. Baumgartner, Travis L. Sunderland","doi":"10.1021/acs.macromol.5c00394","DOIUrl":"https://doi.org/10.1021/acs.macromol.5c00394","url":null,"abstract":"Hydrosilylation is one of the most ubiquitous reactions in silicone chemistry, used to make and cure a variety of products that consumers interact with on a daily basis. A longstanding complication with this reaction is the propensity of platinum catalysts to isomerize terminal alkenes to internal alkenes that are far less reactive toward hydrosilylation. Here, we demonstrate that with the appropriate choice of Si–H substrate and control over the reaction conditions, these internal isomers can be reisomerized to the terminal alkene to then undergo hydrosilylation with Karstedt’s catalyst, an industry standard platinum catalyst. This ultimately leads to hydrosilylation products with no residual isomer content, on time scales relevant for industrial production. Only -SiMe₂H (M′) substrates were capable of producing isomer free products, with -SiMeH- (D′) units as substrates resulting in high (>13 mol %) residual isomerized alkenes. Using this technology, low-isomer silicone polyether materials were synthesized with a final isomer content <1 mol %. Due to the propensity of residual isomerized species to undergo hydrolysis to propionaldehyde and other malodorous acetals, this technology is expected to reduce the odor of residual alkenyl species in silicone polyether materials in a cost-effective manner for industrial production.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"183 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143695469","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":"Roles of Interfaces in Crystallization in Freestanding and Bilayer Polymer Films","authors":"Lingyi Zou, Wenlin Zhang","doi":"10.1021/acs.macromol.4c02871","DOIUrl":"https://doi.org/10.1021/acs.macromol.4c02871","url":null,"abstract":"We apply molecular dynamics simulations to quantify the effects of free surfaces and interfacial regions on crystallization in freestanding and bilayer polymer films. We show that enhanced crystal nucleation in polymer thin films is quantitatively correlated to faster local segmental dynamics induced by free surfaces. When a second layer is deposited onto a semicrystalline film, we observe rapid primary nucleation near the free surface, secondary nucleation near the semicrystalline interface, and slower primary nucleation near the center of the fresh polymer layer, which can result in enhanced crystallization in the interlayer region and impact the interfacial strength. We expect molecular insight into thin-film and bilayer polymer crystallization to help optimize polymer products manufactured by layer-by-layer processes.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"10 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143703675","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":"Precisely Regulating Interchain Aggregation and Film Crystallinity of Quinoidal Terpolymers for High-Performance Eco-friendly Transistors","authors":"Runze Xie, Quanfeng Zhou, Pingzhong Guan, Jinlun Li, Cheng Liu, Miao Qi, Chongqing Yang, Xuanchen Liu, Junkai Xiong, Xiang Ge, Pengfei Zhou, Lianjie Zhang, Junwu Chen, Yi Liu, Xuncheng Liu","doi":"10.1021/acs.macromol.4c02672","DOIUrl":"https://doi.org/10.1021/acs.macromol.4c02672","url":null,"abstract":"The widespread use of toxic halogenated solvents in processing high-performance conjugated polymers raises environmental concerns and hinders large-scale organic electronics production. While the terpolymer approach has improved the donor–acceptor polymer performance, it remains unexplored in quinoidal systems. This study pioneers a terpolymer strategy for quinoidal polymers to enable eco-friendly processing by fine-tuning interchain aggregation and film crystallinity, leading to improved charge mobility and stability in organic field-effect transistors (OFETs). A series of <i>para</i>-azaquinodimethane-based random terpolymers with varied ratios of terthiophene (3T) and quaterthiophene (4T) units are developed, demonstrating that higher 4T content enhances interchain aggregation but reduces solubility, dramatically affecting molecular packing and OFET performance. When processed from chlorobenzene, all terpolymers outperformed reference alternating copolymers, with PA-3T25-4T75 containing 75% 4T achieving the highest hole mobility of 2.26 cm² V^–1 s^–1 due to its most ordered microstructure. Notably, PA-3T75-4T25 with 25% 4T achieves an impressive hole mobility of 2.09 cm² V^–1 s^–1 with tetrahydrofuran as the solvent, marking a record high value for quinoidal polymers processed from eco-friendly solvents. This work underscores the potential of terpolymer design in enhancing both OFET performance and environmental sustainability of quinoidal polymers, contributing to the development of eco-friendly organic electronics.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"33 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143695417","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 Synthesis of Sequence-Defined Oligomers through Orthogonal CuAAC and IrAAC Reactions","authors":"Tingting Qiu, Ningning Song, Shengtao Ding","doi":"10.1021/acs.macromol.4c03204","DOIUrl":"https://doi.org/10.1021/acs.macromol.4c03204","url":null,"abstract":"Abiotic sequence-defined polymers hold tremendous promise for applications in nanotechnology, materials science, biomedicine, and data storage. Yet, their synthesis often demands complex, iterative procedures involving multiple deprotection or activation steps. To address this challenge, we present a highly efficient “AB + AC” orthogonal coupling strategy that integrates copper-catalyzed azide–alkyne cycloaddition (CuAAC) and iridium-catalyzed AAC (IrAAC). This approach leverages the exceptional chemoselectivity of each reaction to construct sequence-defined oligotriazoles without the need for protecting groups. Notably, by employing distinct terminal alkyne and thioalkyne substrates, our method enables precise, stepwise elongation of macromolecular chains on a gram scale, even when incorporating diverse functional monomers, underscoring its practicality for large-scale applications. Comprehensive analyses via size exclusion chromatography, mass spectrometry, and nuclear magnetic resonance techniques confirm the high purity and structural accuracy of the resulting oligomers. Moreover, the clear fragmentation patterns observed in tandem mass spectrometry (MS/MS) highlight the suitability of these triazole-rich architectures for high-fidelity data encoding, thereby paving the way for advanced applications in high-density information storage. Overall, this work not only expands the synthetic toolbox for creating precision polymers but also offers a robust platform for the development of next-generation materials with tunable properties and broad technological relevance.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"57 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143677972","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":"Waterborne Polyurethane Transparent Coatings for Self-Healing at Room Temperature","authors":"Kanyarat Mantala, Daniel Crespy","doi":"10.1021/acs.macromol.4c02732","DOIUrl":"https://doi.org/10.1021/acs.macromol.4c02732","url":null,"abstract":"Waterborne polyurethanes are now widely used for preparing adhesives and coatings. They are considered as a sustainable alternative for solvent-borne applications because of reductions in volatile organic compounds (VOC) emissions. However, imparting a property of self-healing at room temperature to these polyurethanes remains challenging. Herein, we synthesized prepolymers containing thiosulfate groups, which enabled their dispersibility in aqueous solutions. The thiosulfate groups were subsequently hydrolyzed to form disulfide bonds. Recovery of mechanical and optical properties (transmittance) at room temperature was then observed due to dynamic disulfide exchange reactions.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"27 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143666394","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":"Selective Tuning of Benzothiadiazole Functionality Enables High Crystallinity and Mobility in Regiorandom n-Type Polymers for Organic Field-Effect Transistors","authors":"Panagiota Kafourou, Qiao He, Xiantao Hu, Mohamad Insan Nugraha, Wen Liang Tan, Joel Luke, Bowen Ding, Christopher R. McNeill, Thomas D. Anthopoulos, Martin Heeney","doi":"10.1021/acs.macromol.4c02854","DOIUrl":"https://doi.org/10.1021/acs.macromol.4c02854","url":null,"abstract":"We report three novel donor–acceptor (D–A) copolymers sharing a common fused donor unit (CDTT) but differing in the functionalization of the benzothiadiazole (BT) acceptor unit. Acceptors bearing two cyano groups (DCNBT) are compared to novel acceptors bearing one cyano and one fluorine group (FCNBT) or one nitro and one fluoro group (NO₂FBT). The choice of the acceptor has a significant effect on the optoelectronic properties of the resulting polymers. In organic field-effect transistor (OFET) devices, PCDTT-DCNBT exhibited moderate performance with an electron mobility of 0.031 cm² V^–1 s^–1, whereas PCDTT-FCNBT demonstrated significantly improved electron mobility (0.4 cm² V^–1 s^–1). The improved performance is attributed to increased backbone linearity combined with a more coplanar backbone and high thin-film crystallinity. In comparison, the presence of the nitro group is shown to have a detrimental impact, with a blue-shifted absorption and a 0.2 eV increase in band gap compared to the cyanated polymers. Steric effects are shown to limit the nitro group’s π-accepting capability and result in reduced device performance, with an electron mobility of 0.024 cm² V^–1 s^–1. This study introduces a new BT building block and highlights that substituent tuning via cyano and fluorine groups is an effective approach for modulating polymer morphology and electron transport.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"51 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143666438","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":"Stress-Free Two-Way Liquid Crystalline–Semicrystalline Shape Memory Copolymer Actuators with Multistimuli-Responsive Actuation Behaviors","authors":"Yahui Wang, Shufen Ye, Shasha Li, Yanqing Li, Rong Yang","doi":"10.1021/acs.macromol.4c02171","DOIUrl":"https://doi.org/10.1021/acs.macromol.4c02171","url":null,"abstract":"Stress-free two-way shape memory semicrystalline networks have garnered significant interest due to their ability to undergo reversible shape changes under external stimuli without repeated programming. However, their reversible actuation strain is often limited by the low anisotropy of the skeleton phase and the low crystallization rate and crystallinity of the actuation phase. In this study, we present a novel approach to developing two-way shape memory actuators utilizing liquid crystalline polymers as the skeleton phase, achieving high actuation strain and multistimuli-responsive behaviors. Specifically, we have designed and synthesized multiblock liquid crystalline–semicrystalline copolymers, poly(4,4’-bis(6-hydroxyhexyloxy)biphenyl phenylsuccinate)-poly(ethylene glycol) (PBDPS-PEG), and characterized their reversible shape changes in response to various external stimuli. The PBDPS block, easily stretchable within the liquid crystal phase, induces the epitaxial crystallization of the PEG block, forming microphase-separated ordered lamellar structures that facilitate reversible shape changes and anisotropic swelling behaviors under thermal, water absorption, and humidity stimuli. PBDPS-PEG actuators extend their functionality to grippers capable of manipulating objects across diverse environmental conditions and serve as humidity sensors, reflecting ambient humidity levels through reversible shape changes. This study highlights the potential of liquid crystalline–semicrystalline copolymer actuators in applications such as soft robotics, biomedical devices, and environmental sensors.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"46 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143666395","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":"Solid-State Processing of In Situ Blended Prepolymer with Z–N Synthesized UHMWPE: Role of the Prepolymer","authors":"Ravindra P. Gote, Jiayi Zhao, Dario Romano, Sanjay Rastogi","doi":"10.1021/acs.macromol.4c03097","DOIUrl":"https://doi.org/10.1021/acs.macromol.4c03097","url":null,"abstract":"Ultrahigh molecular weight polyethylene (UHMWPE) synthesized using single-site catalytic systems, adopting a homogeneous bis(phenoxy-imine) Ti catalyst or half-metallocene Cr catalyst, under controlled polymerization conditions exhibits a unique low-entanglement state that enables solvent-free solid-state processing into strong, uniaxially and biaxially oriented films having unprecedented tensile strength and tensile modulus. The use of bis(phenoxy-imine) titanium catalysts supported on MgCl₂-based dual activator/support systems has been also shown to facilitate the heterogeneous synthesis of low-entangled UHMWPE, offering a promising industrial route. Conversely, commercially viable heterogeneous Ziegler–Natta catalysts yield UHMWPE with a high number of entanglements per chain (en-UHMWPE), necessitating solution spinning for fiber production. This study aims to investigate an industrially viable, solvent-free processing route for en-UHMWPE using commercial Ziegler–Natta catalysts. Herein, we synthesize UHMWPE sample via a one-pot, two-step protocol, incorporating a relatively low molar mass component (prepolymer) into the UHMWPE matrix, thus achieving a molecular blend between low and ultrahigh molar mass polymers. The sample exhibits excellent solid-state processability, achieving a remarkable draw ratio of up to 148× in a narrow temperature window. This resulted in outstanding mechanical properties of 1.6 and 127 N/tex of tensile strength and tensile modulus, respectively, for a Z–N synthesized polymer. Wide-angle X-ray diffraction (WAXD) measurements demonstrate a strong correlation between the draw ratio and the chain orientation, indicating a high degree of molecular alignment at higher draw ratios. In the drawn samples, solid-state nuclear magnetic resonance spectroscopy reveals the presence of a highly mobile amorphous fraction in the prepol/en-UHMWPE blend. The presence of the mobile fraction, arising from the melt-crystallized component in the drawn samples, is further supported by differential scanning calorimetry, WAXD, and small-angle X-ray scattering. On comparing with the low-entangled/disentangled samples synthesized using the single-site catalytic systems, the studies demonstrate that in the Z–N samples investigated here, the low molar mass component acts as an effective consolidant facilitating solid-state processing in a relatively narrow temperature window. The study emphasizes the influence of polymerization conditions and molecular characteristics in pursuing fundamental studies, especially on ultrahigh molar mass polymers.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"56 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143660653","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":"Fluorine-Free Sulfonated Poly(sulfone triazole)s with a Pendant Phosphaphenanthrene Moiety for Proton Exchange Membrane Applications","authors":"Bholanath Ghanti, Susanta Banerjee","doi":"10.1021/acs.macromol.5c00277","DOIUrl":"https://doi.org/10.1021/acs.macromol.5c00277","url":null,"abstract":"Fluorinated proton exchange membranes (PEMs), such as Nafion, are the current state-of-the-art polymers, but they pose environmental challenges, driving the need for more sustainable fluorine-free alternatives. In this work, a phosphaphenanthrene-based bisalkyne monomer, 6-(1,1-bis(4-(prop-2-yn-1-yloxy)phenyl)ethyl)dibenzo[<i>c</i>,<i>e</i>][1,2]oxaphosphinine 6-oxide (DPAK), has been prepared. Utilizing this monomer (DPAK), a set of sulfonated poly(sulfone triazole)s with a pendant phosphaphenanthrene unit in the hard (hydrophobic) and soft (hydrophilic) segments of the copolymer have been designed and synthesized by the “click” reaction with various degrees of sulfonation values. The chemical structures of the copolymers were confirmed by various spectroscopic (FTIR, NMR, and XPS) techniques. The salt-form sulfonated poly(sulfone triazole) (SODPSNa-XX) copolymers exhibited high solubility in polar aprotic solvents. The acid-form sulfonated poly(sulfone triazole) (SODPSH-XX) copolymers exhibited high thermal, mechanical, and viscoelastic properties. Despite the absence of fluorinated moieties, the SODPSH-XX membranes possess moderate water absorption properties and show high-dimensional stability. The morphological (AFM, FESEM, and HRTEM) investigations of the SODPSH-XX membranes indicate the formation of an interconnected and well-segregated phase morphology, which created interconnected ionic cluster-like channels for the agile proton migration process. The SODPSH-90 membrane demonstrates much higher proton conductivity at 80 and 90 °C (σ: 100 and 112 mS/cm) than the few earlier reported fluorine-free sulfonated PEMs with comparable IEC_w values. The SODPSH-XX copolymers exhibited high durability, mainly associated with bulky cyclic phosphaphenanthrene and sulfonyl units in the copolymer backbone. Also, the SODPSH-70 to -90 membranes demonstrated better oxidative stability in Fenton’s reagent at 80 °C.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"17 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143666396","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":"Benchmarking the Elastic Modulus of Conjugated Polymers with Nanoindentation","authors":"Sri Harish Kumar Paleti, Shuichi Haraguchi, Zhiqiang Cao, Mariavittoria Craighero, Joost Kimpel, Zijin Zeng, Przemyslaw Sowinski, Di Zhu, Judith Pons i Tarrés, Youngseok Kim, Qifan Li, Junda Huang, Alexei Kalaboukhov, Besira Mihiretie, Simone Fabiano, Xiaodan Gu, Christian Müller","doi":"10.1021/acs.macromol.4c03081","DOIUrl":"https://doi.org/10.1021/acs.macromol.4c03081","url":null,"abstract":"The elastic modulus is a critical parameter for the design of conjugated polymers for wearable electronics and correlates with electrical and thermal transport. Yet, widely different values have been reported for the same material because of the influence of processing and measurement conditions, including the temperature, mode, direction, and time scale of deformation. Thus, results obtained via different methods are usually not considered to be comparable. Here, disparate techniques from nanoindentation to tensile testing of free-standing films or films on water, buckling analysis, dynamic mechanical thermal analysis, oscillatory shear rheometry, and atomic force microscopy are compared. Strikingly, elastic modulus values obtained for the same batch of regioregular poly(3-hexylthiophene) differ by a factor of less than four, which suggests that an approximate comparison is possible. Considering the small amount of material that is typically available, nanoindentation in combination with creep analysis is identified as a reliable method for probing the elastic modulus of films with widely different elastic moduli ranging from less than 0.1 GPa in the case of a polythiophene with oligoether side chains to several GPa for polymers without side chains. Since films can display anisotropic elastic modulus values, it is proposed that nanoindentation is complemented with an in-plane technique such as tensile testing to ensure a full characterization using different modes of deformation.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"10 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143660655","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}