Macromolecules最新文献

Investigation of the Nanomechanical Behaviors of Polymer Single Crystals by Atomic Force Microscopy Nanoindentation 聚合物单晶纳米力学行为的原子力显微镜研究

IF 5.5 1区化学

Macromolecules Pub Date : 2026-10-20 DOI: 10.1021/acs.macromol.6c02126

Yongkang Deng,Peng Yang,Xiaoye Zhang,Ziwen Ma,Yu Song,Wenke Zhang

{"title":"Investigation of the Nanomechanical Behaviors of Polymer Single Crystals by Atomic Force Microscopy Nanoindentation","authors":"Yongkang Deng,Peng Yang,Xiaoye Zhang,Ziwen Ma,Yu Song,Wenke Zhang","doi":"10.1021/acs.macromol.6c02126","DOIUrl":"https://doi.org/10.1021/acs.macromol.6c02126","url":null,"abstract":"Understanding the nanomechanical behavior of crystalline domains is crucial for establishing structure–property relationships in semicrystalline polymers. In this study, atomic force microscopy (AFM) nanoindentation on compliant polydimethylsiloxane (PDMS) substrates was used to quantify the Young’s modulus, fracture force, and deformation mechanisms of ultrathin polymer single crystals, including polyethylene (PE), poly(ethylene oxide) (PEO), poly(l-lactic acid) (PLLA), poly(ε-caprolactone) (PCL), and polyamide 66 (PA 66). Although several crystals showed comparable Young’s moduli, their fracture behaviors differed markedly. PE and PEO exhibited ductile deformation with permanent imprints and material pile-up, whereas PLLA, PCL, and PA 66 underwent brittle fragmentation. Cyclic loading–unloading further revealed pronounced crystal slip in PEO and hidden slip in thickness-stepped PE, while the other crystals remained mainly elastic before failure. These findings highlight force-activated chain dynamics as a key factor governing crystalline stem slip and the resulting brittle-to-ductile transition in polymer crystals.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"14 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2026-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149221631","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

Hierarchical Dynamics and Phase Transitions in Wedge-Shaped Side-Chain Liquid Crystalline Polymers with Varying Spacer Lengths 具有不同间隔长度的楔形侧链液晶聚合物的层次动力学和相变

IF 5.5 1区化学

Macromolecules Pub Date : 2026-10-20 DOI: 10.1021/acs.macromol.6c01947

Minghe Sun,Yining Fan,Pingchuan Sun,Shuang Yang,Er-Qiang Chen

{"title":"Hierarchical Dynamics and Phase Transitions in Wedge-Shaped Side-Chain Liquid Crystalline Polymers with Varying Spacer Lengths","authors":"Minghe Sun,Yining Fan,Pingchuan Sun,Shuang Yang,Er-Qiang Chen","doi":"10.1021/acs.macromol.6c01947","DOIUrl":"https://doi.org/10.1021/acs.macromol.6c01947","url":null,"abstract":"As an important class of graft polymers, side-chain liquid crystalline polymers (SCLCPs) containing anisotropic mesogenic groups exhibit complex molecular dynamics that are closely coupled with hierarchical structural evolution. In this study, using various characterization techniques, we investigate the phase structures and viscoelastic behavior of a series of wedge-shaped SCLCPs, denoted as CxBP (x = 1, 3, 7), where x is the number of methylene units in the spacer linking the wedge-shaped mesogenic side group to the polynorbornene backbone. CxBPs form a hexagonal columnar phase (ColH), with multichain supramolecular columns serving as the basic building block arising from microphase separation of the main and side chains. Upon cooling from the isotropic state, CxBPs show unique multistep increases in modulus through four distinct stages (I–IV) with shear moduli of 104, 105, 107, and 108 Pa, respectively, separated by three relaxation/transition processes (α, β, γ). When approaching to –100 °C, a δ-relaxation further raises the modulus to ∼109 Pa. The α- and γ-processes correspond to first-order transitions: the isotropic-to-ColH transition at ∼90 °C and partial ordering of the side-chain alkyl tails at ∼0 °C, respectively. Notably, the β-process is a predominantly noncooperative relaxation following Arrhenius behavior with an activation energy of ∼300 kJ/mol, attributed to the motion of mesogens on the side chains. Freezing of this motion transforms the ColH from a “mobile” to a “mesogen-arrested” state, increasing the shear modulus by 2 orders of magnitude from stage II to stage III. We find that a longer spacer lowers the β-relaxation temperature. With a single methylene unit as the spacer, C1BP shows β-relaxation partially overlapping with the α-process. Extending the spacer length to three or more methylene units (C3BP, C7BP) enables sufficient dynamic decoupling of the main and side chains, yielding a wider stage II with a shear modulus of 105 Pa.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"1 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2026-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149218895","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

Side-Chain Ionicity Governs Heavy Oxidative Doping and Electronic Structure Evolution in Conjugated Polyelectrolytes 侧链离子性控制共轭聚电解质重氧化掺杂和电子结构演化

IF 5.5 1区化学

Macromolecules Pub Date : 2026-10-20 DOI: 10.1021/acs.macromol.6c02121

Xiang-Ren Chen,Guan-Lin Chen,Ji Hyun Jung,Haim Kwon,Jhih-Min Lin,Han Young Woo,Cheng-Liang Liu

{"title":"Side-Chain Ionicity Governs Heavy Oxidative Doping and Electronic Structure Evolution in Conjugated Polyelectrolytes","authors":"Xiang-Ren Chen,Guan-Lin Chen,Ji Hyun Jung,Haim Kwon,Jhih-Min Lin,Han Young Woo,Cheng-Liang Liu","doi":"10.1021/acs.macromol.6c02121","DOIUrl":"https://doi.org/10.1021/acs.macromol.6c02121","url":null,"abstract":"Side chains influence not only solubility but also solid-state molecular organization and charge transport. Here, we establish side-chain ionicity as a decisive variable governing heavy oxidative doping. We compared poly(4H-cyclopenta[2,1-b:3,4-b′]dithiophene-alt-2,1,3-benzothiadiazole) (PCPDTBT) derivatives sharing an identical conjugated backbone but distinct side-chain functionalities: anionic CPE-Na, neutral CP, and cationic CPE-Br. Their solid-state organization spanned edge-on semicrystalline packing to an amorphous structure lacking detectable long-range order, yielding distinct doping behaviors. Only amorphous CPE-Br accommodated extensive dopant uptake through its loosely packed cationic network and preserved transport connectivity. This high local dopant density reorganized the density of states rather than rigidly shifting the Fermi level, reversing the Seebeck coefficient sign and yielding S = –34.8 μV K–1 at 20 mM FeCl3. To our knowledge, this is the first polarity inversion in a conjugated polyelectrolyte. Side-chain ionicity is therefore a molecular design parameter for oxidative doping, and long-range crystallinity is unnecessary for polarity inversion.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"3 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2026-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149221635","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

Against the Segmental Relaxation of the Chain Network: Activating the Ductile Mechanism of Both Glassy and Semicrystalline PLLA 反对链网的节段松弛：激活玻璃态和半晶PLLA的延性机制

IF 5.5 1区化学

Macromolecules Pub Date : 2026-10-20 DOI: 10.1021/acs.macromol.6c00777

Xabier Larrañaga,Brian J. Rodriguez,Jose R. Sarasua,Ester Zuza

{"title":"Against the Segmental Relaxation of the Chain Network: Activating the Ductile Mechanism of Both Glassy and Semicrystalline PLLA","authors":"Xabier Larrañaga,Brian J. Rodriguez,Jose R. Sarasua,Ester Zuza","doi":"10.1021/acs.macromol.6c00777","DOIUrl":"https://doi.org/10.1021/acs.macromol.6c00777","url":null,"abstract":"The mechanical behavior of semicrystalline poly(l-lactide) (PLLA) is heavily influenced by its complex chain structure, which continues to be a key focus in ongoing research regarding its ability to exhibit ductile behavior. In this work, the brittle-ductile transition (BDT) of the amorphous structure of PLLA is studied in relation to its physical aging, and following the yielding of amorphous structure, the deformation of crystalline PLLA spherulites is closely examined. The significant impact of physical aging on amorphous PLLA’s mechanical properties is evident as the least aged samples show a BDT at –30 °C, aligning more closely with Vincent’s plot expectations, whereas more aged samples only exhibit ductility above 40 °C. Additionally, brittle specimen rupture is observed when the chain pullout force is reached, which increases with decreasing temperature and governs the brittle failure mechanism. The wide range of aging times and testing temperatures enables an in-depth analysis of the crazing behavior, highlighting its temperature and time dependence as an activated process. Upon yielding of the amorphous phase, various deformation modes are observed in the crystalline spherulite studies, confirming the chain network's ability to disintegrate crystalline structures and transition into a less ordered configuration as indicated by the nanoindentation and Raman spectroscopy measurements. This study conceives PLLA, not as an inherently brittle polymer, but as one whose structure needs to restore its constrained activation capacity.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"13 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2026-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149218898","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

Depletion Effect during the Synthesis of Conductive Segregated-Network Graphene-Polymer Composites 导电分离网络石墨烯-聚合物复合材料合成过程中的损耗效应

IF 5.5 1区化学

Macromolecules Pub Date : 2026-10-20 DOI: 10.1021/acs.macromol.6c01546

Khandaker Umaiya,Prabodha G. Abeykoon,Brenden Ferland,Douglas H. Adamson

{"title":"Depletion Effect during the Synthesis of Conductive Segregated-Network Graphene-Polymer Composites","authors":"Khandaker Umaiya,Prabodha G. Abeykoon,Brenden Ferland,Douglas H. Adamson","doi":"10.1021/acs.macromol.6c01546","DOIUrl":"https://doi.org/10.1021/acs.macromol.6c01546","url":null,"abstract":"The in situ growth of crosslinked polymer chains within the confined, nanometer-scale gaps of a graphene network governs the electrical conductivity of graphene-based polymer composites, yet the underlying polymerization behavior remains poorly understood. Here, we investigate the depletion effect that drives graphene sheets in a segregated network to move closer together as the continuous phase polymerizes. By monitoring the electrical resistance and reaction temperature of graphene-stabilized high internal phase emulsions of styrene, methyl methacrylate, and t-butyl acrylate, we provide evidence of the depletion effect, a phenomenon in which high-molecular-weight polymer chains are excluded from confined interfaces, thereby enhancing graphene sheet-to-sheet contact and reducing electrical resistance. Systematic experiments reveal that polymerization parameters, including temperature, initiator presence, and crosslinking, govern conductivity transitions, with the resistance drop tracking the auto-acceleration exotherm and the onset of crosslinker-driven coil growth. Consistent with this interpretation, 4-point probe measurements on graphene films show that opposite-sign Q–e pairs (PMMA-DVB, PS-EGDMA, and PS-TMPTA) yield sheet resistances that are an order of magnitude lower than same-sign pairs (PS-DVB, PMMA-EGDMA, and PMMA-TMPTA), consistent with the predicted ordering due to faster crosslinker incorporation. These findings establish crosslinker reactivity as a kinetic handle on polymer network evolution under confinement and demonstrate electrical resistance as a sensitive in situ reporter of polymer growth.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"11 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2026-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149218896","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

Polymer Knots in Thin Slit-Confined Melts: Thickness Dependence, Local Effects, and Stiffness 薄缝约束熔体中的聚合物结：厚度依赖、局部效应和刚度

IF 5.5 1区化学

Macromolecules Pub Date : 2026-10-19 DOI: 10.1021/acs.macromol.6c01338

Maurice Pierre Schmitt,Hendrik Meyer,Peter Virnau

引用次数: 0

Acid-Triggered Cyclization Enables Selective Depolymerization of Robust Polyamides for Recovery of Monomer Derivatives 酸触发环化使稳健聚酰胺的选择性解聚恢复单体衍生物

IF 5.5 1区化学

Macromolecules Pub Date : 2026-10-19 DOI: 10.1021/acs.macromol.6c01475

Kousuke Tsuchiya,Yukiya Osaki,Sayuri Tanaka,Nanaka Takeuchi,Takuya Katashima,Takamasa Sakai

{"title":"Acid-Triggered Cyclization Enables Selective Depolymerization of Robust Polyamides for Recovery of Monomer Derivatives","authors":"Kousuke Tsuchiya,Yukiya Osaki,Sayuri Tanaka,Nanaka Takeuchi,Takuya Katashima,Takamasa Sakai","doi":"10.1021/acs.macromol.6c01475","DOIUrl":"https://doi.org/10.1021/acs.macromol.6c01475","url":null,"abstract":"Abstract The development of polymeric materials that combine practical performance with selective degradability is an important goal in sustainable materials research. Selective degradation into defined small molecules offers a promising strategy for the deconstruction and potential chemical recycling of polymeric materials. However, extending this concept to mechanically robust polyamides remains challenging because of the high stability of their amide backbones. In this study, we used microbially produced poly(ε-lysine) (PLys) as a renewable feedstock to construct biobased polyamides that undergo rapid acid-mediated depolymerization. The amino groups at the α-carbons of PLys were modified with isothiocyanates bearing different side groups to afford thiourea-functionalized PLys derivatives. These thiourea moieties were selectively cleaved through an acid-mediated cyclization reaction, yielding the corresponding cyclic lysine derivatives as discrete depolymerization products. Structural analyses revealed that the thiourea-modified PLys underwent complete depolymerization in the presence of acids such as hydrochloric acid, and that the cyclic lysine derivatives could be recovered without specialized purification. Moreover, thiourea modification converted PLys into amorphous polyamides that formed robust films and exhibited a high storage modulus at ambient temperature. The polyamides could also be cross-linked using multifunctional isothiocyanates, and the resulting network materials exhibited shape-memory behavior together with a high storage modulus. Overall, this study establishes a molecular design strategy for mechanically robust biobased polyamides that undergo rapid acid-triggered depolymerization into defined cyclic lysine derivatives, opening a route toward selectively deconstructable polyamides for sustainable materials applications.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"1 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2026-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149210160","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

Spontaneous Zwitterionic Polycondensation for N,S,P-Heteroatom Polymers and Ring Formation N，S， p -杂原子聚合物的自发两性离子缩聚和环的形成

IF 5.5 1区化学

Macromolecules Pub Date : 2026-10-19 DOI: 10.1021/acs.macromol.6c01915

Yunchao Zheng,Wei Wei,Huiming Xiong

{"title":"Spontaneous Zwitterionic Polycondensation for N,S,P-Heteroatom Polymers and Ring Formation","authors":"Yunchao Zheng,Wei Wei,Huiming Xiong","doi":"10.1021/acs.macromol.6c01915","DOIUrl":"https://doi.org/10.1021/acs.macromol.6c01915","url":null,"abstract":"N,S,P-heteroatom polymers have been synthesized through spontaneous zwitterionic polycondensation of nucleophilic nonactivated aziridines and electrophilic Lawesson’s reagent at high concentrations. The evolution of zwitterionic linear polymers and neutral macrocycles during the copolymerization process has been unveiled through an efficient end-functionalization strategy coupled with a robust Montmorillonite clay-based purification protocol for selective isolation of cyclic compounds, combined with characterizations by high-resolution mass spectrometry, time-resolved 1H NMR, and absolute molecular weight SEC. The intramolecular ring closure can be a dominant process in the polycondensation to yield macrocycles up to 90% in a highly concentrated reactant solution. By comparing with the kinetics model developed specifically for the irreversible AB-type condensation polymerization, which incorporates the kinetics of the linear growth and the cyclization under a Gaussian statistics assumption, the propensity of cyclization has been ascribed to the synergistic seeding-like effects from the inherent cyclic conformation of the zwitterionic oligomers at the early stage of polymerization, reinforced by the electrostatic interaction in the zwitterionic system. DFT calculations also reveal the correlation of cyclization tendency with the conformational structures of the oligomers and the substituents. The solvent, temperature, and Lewis acid additive have been utilized to regulate ionic interactions, association of the zwitterionic intermediates, and the polycondensation process, thus tuning the composition and topology of the products. The fabricated transparent polymer film exhibits a high refractive index of nD25 ∼ 1.73.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"55 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2026-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149210894","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

Sacrificial H-Bond Arrays Reinforce Dynamic Covalent Networks for Ultra-tough, Solvent-Resistant, and Self-healable Polyurethanes 牺牲氢键阵列增强动态共价网络的超坚韧，耐溶剂和自愈合聚氨酯

IF 5.5 1区化学

Macromolecules Pub Date : 2026-10-19 DOI: 10.1021/acs.macromol.6c02217

Hong Wang,Ning Ding,Chaoyu Chen,Weijun Yang,Deyu Niu,Pibo Ma,Songqi Ma,Pengwu Xu,Piming Ma

{"title":"Sacrificial H-Bond Arrays Reinforce Dynamic Covalent Networks for Ultra-tough, Solvent-Resistant, and Self-healable Polyurethanes","authors":"Hong Wang,Ning Ding,Chaoyu Chen,Weijun Yang,Deyu Niu,Pibo Ma,Songqi Ma,Pengwu Xu,Piming Ma","doi":"10.1021/acs.macromol.6c02217","DOIUrl":"https://doi.org/10.1021/acs.macromol.6c02217","url":null,"abstract":"Abstract Reconciling high toughness and solvent resistance with dynamic adaptability under mild conditions remains challenging for self-healable polymer networks. Here, we report a dual-dynamic polyurethane elastomer (PCL-ADH-FBR) in which an acylurea-derived, high-density hydrogen-bonding array is integrated with a dynamic boronic ester network. FTIR analysis indicates that 84.6% of the C=O groups participate in hydrogen bonding. The resulting elastomer reaches a fracture energy of 307 kJ/m2, a toughness of 477 MJ/m3, and a tensile strength of 61.2 MPa. In situ synchrotron X-ray scattering reveals sequential energy dissipation through hydrogen-bond disruption and strain-induced crystallization of the PCL segments. The dense hydrogen-bond network also restricts solvent ingress. The material retains more than 85% of its tensile strength after 7 days in water and recovers more than 90% of its tensile properties after 12 h exposure to 12 tested solvents followed by drying at 60 °C for 24 h. After healing at 90 °C for 24 h, the sample recovers 98.5% of its tensile strength and 99.4% of its elongation at break, and the material can be repeatedly reprocessed. A flexible triboelectric nanogenerator fabricated from PCL-ADH-FBR delivers an open-circuit voltage of 54.4 V and recovers 97% of its output after damage and healing. These results support a physically reinforced dynamic-network strategy for combining mechanical robustness, environmental stability, and functional recoverability in polyurethane elastomers.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"9 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2026-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149210158","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

Transforming Cyclic Allenes into Precision Macromolecular Building Blocks 将环烯转化为精密大分子构建块

IF 5.5 1区化学

Macromolecules Pub Date : 2026-10-19 DOI: 10.1021/acs.macromol.6c02461

Xuefen Liu,Lefei Yu,Kerry M. Hanson,William J. Neary

{"title":"Transforming Cyclic Allenes into Precision Macromolecular Building Blocks","authors":"Xuefen Liu,Lefei Yu,Kerry M. Hanson,William J. Neary","doi":"10.1021/acs.macromol.6c02461","DOIUrl":"https://doi.org/10.1021/acs.macromol.6c02461","url":null,"abstract":"Abstract Ring-opening allene metathesis polymerization (ROAlMP) provides direct access to polyallenamers containing reactive allene functionality within the polymer backbone, yet achieving controlled polymerization has remained a major challenge. Here, we report an additive-assisted ROAlMP strategy in which triphenylphosphine (PPh3) or 3,5-dichloropyridine (3,5-Cl2Py) modulates catalyst speciation to enable controlled polymerization behavior, affording polyallenamers with predictable molecular weight (Mn up to 70 kDa) and moderate dispersities (Đ &lt; 1.4). This enhanced control enables the synthesis of di- and triblock copolymers spanning three distinct classes of metathesis-active monomers, including cyclic alkenes, diynes, and cyclic allenes, while also providing access to self-assembled nanostructured materials containing allene-rich domains. We further demonstrate that these domains can be selectively stabilized through backbone [2 + 2] photocrosslinking, a capability inherently encoded within the polymer backbone and achieved without additional monomer functionalization. Finally, to illustrate the unique chemical opportunities afforded by backbone allenes, the resulting polyallenamers were subjected to iodonium-induced annulation, generating naphthalene-containing polymer backbones with pronounced changes in their photophysical behavior. Collectively, these results establish additive-controlled ROAlMP as a versatile platform for precision polyallenamer synthesis and highlight the unique materials opportunities enabled by allene-containing polymer backbones.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"42 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2026-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149210163","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