IF 4.5 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2026-01-07 DOI: 10.1016/j.polymer.2025.129511

Selemon Bekele , Jordan J. Winetrout , Davide L. Simone , Vikas Varshney

引用次数: 0

Photothermal driven shape memory polymer based on MXene-grafted-polycaprolactone with fast response and easy recyclability 基于mxene接枝聚己内酯的光热驱动形状记忆聚合物，响应快，易于回收

IF 4.5 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2026-01-07 DOI: 10.1016/j.polymer.2026.129554

Jingyue Zhang , Haoge Cheng , Yuanqi Jiao , Yixin Ye , Yushu Wang , Alaa S. Abd-El-Aziz , Xinyue Zhang , Ning Ma

As a class of emerging smart materials, light-driven shape memory polymers (SMPs) have attracted a lot of attention and have been applied in many frontier fields. However, the vast majority of light-driven SMPs are limited by the efficiency of the photothermal conversion components and the dispersion with matrices, which seriously affects the development. At the same time, the fabrication of SMPs with near-infrared (NIR) light non-contact driving and recyclable reprocessing remains a challenge. In this work, NIR light-driven shape memory materials with stable and rapid light-response were prepared by physically blending MXene grafted with polycaprolactone (PCL) and polylactic acid (PLA). By modifying MXene nanosheets with PCL, the highly polar MXene nanosheets were homogeneously dispersed within the resin matrix. Meanwhile, the PLA/MXene-g-PCL composites demonstrated attractive light-driven shape memory performance under NIR light irradiation because of high photothermal conversion efficiency of MXene nanosheets. In addition, the composites also showed potential as a non-contact driven grab and release device in some conditions. More importantly, the mechanical, photothermal and shape memory properties of the PLA/MXene-g-PCL composites remained stable during five hot press cycles of reprocessing, which greatly enhanced their reliability as shape memory materials and prolonged their service lifetime.

作为一类新兴的智能材料，光驱动形状记忆聚合物（SMPs）受到了广泛的关注，并在许多前沿领域得到了应用。然而，绝大多数光驱动smp受到光热转换元件效率和与基体色散的限制，严重影响了其发展。同时，采用近红外（NIR）光非接触驱动和可回收再加工的smp的制备仍然是一个挑战。通过物理共混MXene接枝聚己内酯（PCL）和聚乳酸（PLA），制备了具有稳定、快速光响应的近红外驱动形状记忆材料。用PCL修饰MXene纳米片，使高极性MXene纳米片均匀地分散在树脂基体中。同时，由于MXene纳米片具有较高的光热转换效率，PLA/MXene-g- pcl复合材料在近红外光照射下表现出良好的光驱动形状记忆性能。此外，在某些条件下，复合材料也显示出作为非接触驱动抓取和释放装置的潜力。更重要的是，PLA/MXene-g-PCL复合材料的力学性能、光热性能和形状记忆性能在5个热压再加工循环中保持稳定，大大提高了其作为形状记忆材料的可靠性，延长了其使用寿命。

{"title":"Photothermal driven shape memory polymer based on MXene-grafted-polycaprolactone with fast response and easy recyclability","authors":"Jingyue Zhang , Haoge Cheng , Yuanqi Jiao , Yixin Ye , Yushu Wang , Alaa S. Abd-El-Aziz , Xinyue Zhang , Ning Ma","doi":"10.1016/j.polymer.2026.129554","DOIUrl":"10.1016/j.polymer.2026.129554","url":null,"abstract":"<div><div>As a class of emerging smart materials, light-driven shape memory polymers (SMPs) have attracted a lot of attention and have been applied in many frontier fields. However, the vast majority of light-driven SMPs are limited by the efficiency of the photothermal conversion components and the dispersion with matrices, which seriously affects the development. At the same time, the fabrication of SMPs with near-infrared (NIR) light non-contact driving and recyclable reprocessing remains a challenge. In this work, NIR light-driven shape memory materials with stable and rapid light-response were prepared by physically blending MXene grafted with polycaprolactone (PCL) and polylactic acid (PLA). By modifying MXene nanosheets with PCL, the highly polar MXene nanosheets were homogeneously dispersed within the resin matrix. Meanwhile, the PLA/MXene-g-PCL composites demonstrated attractive light-driven shape memory performance under NIR light irradiation because of high photothermal conversion efficiency of MXene nanosheets. In addition, the composites also showed potential as a non-contact driven grab and release device in some conditions. More importantly, the mechanical, photothermal and shape memory properties of the PLA/MXene-g-PCL composites remained stable during five hot press cycles of reprocessing, which greatly enhanced their reliability as shape memory materials and prolonged their service lifetime.</div></div>","PeriodicalId":405,"journal":{"name":"Polymer","volume":"345 ","pages":"Article 129554"},"PeriodicalIF":4.5,"publicationDate":"2026-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145956726","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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

Machine learning prediction of mechanical properties of polyolefins from stress-strain curves 基于应力-应变曲线的聚烯烃力学性能机器学习预测

IF 4.5 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2026-01-07 DOI: 10.1016/j.polymer.2026.129574

Lekang Zhang , Xiaoyu Sun , Jingqing Li , Lunyang Liu , Tao Liao , Ying Lu , Wenbo Yuan , Hongyuan Chen , Hongfei Li , Yongfeng Men , Shichun Jiang

Polyolefins remain the most widely produced polymers globally, yet progress in their performance optimization is limited by the intricate relationships among processing conditions, microstructure, and mechanical properties. We developed a machine learning framework trained on experimentally acquired, multi-source datasets covering polyethylene, polypropylene, and polybutene-1 prepared by compression molding, extrusion, and injection molding. Nine algorithms were systematically evaluated for predicting Young's modulus, elongation at break, and tensile strength. Among them, Random Forest and Extreme Gradient Boosting (XGB) delivered superior accuracy with R² > 0.80 for polypropylene and polybutene-1, effectively capturing nonlinear processing-structure-property correlations. Model interpretation revealed test temperature, sample thickness, and processing method as the most influential variables, consistent with established polymer physics. Furthermore, global models trained on fused multi-material datasets performed within 5% of material-specific models, demonstrating the reliability of data fusion for small-sample learning. The engineering stress-strain curve reconstruction using XGB achieved R² > 0.85, highlighting the framework’s robustness. This work establishes a data-driven route for understanding and predicting mechanical properties of polyolefins, offering quantitative insights toward accelerated polymer design and processing optimization.

聚烯烃仍然是全球生产最广泛的聚合物，但其性能优化的进展受到加工条件、微观结构和力学性能之间复杂关系的限制。我们开发了一个机器学习框架，对实验获得的多源数据集进行训练，这些数据集包括聚乙烯、聚丙烯和通过压缩成型、挤出和注塑成型制备的聚丁烯-1。九种算法系统地评估预测杨氏模量，断裂伸长率和抗拉强度。其中，随机森林和极端梯度增强（XGB）对聚丙烯和聚丁烯-1的精度为R2 >； 0.80，有效捕获非线性加工-结构-性质相关性。模型解释显示，测试温度、样品厚度和处理方法是影响最大的变量，与已建立的聚合物物理一致。此外，在融合的多材料数据集上训练的全球模型在5%的特定材料模型内执行，证明了数据融合用于小样本学习的可靠性。利用XGB重建工程应力-应变曲线的R2 >； 0.85，突出了框架的鲁棒性。这项工作为理解和预测聚烯烃的机械性能建立了一条数据驱动的路线，为加速聚合物设计和加工优化提供了定量的见解。

{"title":"Machine learning prediction of mechanical properties of polyolefins from stress-strain curves","authors":"Lekang Zhang , Xiaoyu Sun , Jingqing Li , Lunyang Liu , Tao Liao , Ying Lu , Wenbo Yuan , Hongyuan Chen , Hongfei Li , Yongfeng Men , Shichun Jiang","doi":"10.1016/j.polymer.2026.129574","DOIUrl":"10.1016/j.polymer.2026.129574","url":null,"abstract":"<div><div>Polyolefins remain the most widely produced polymers globally, yet progress in their performance optimization is limited by the intricate relationships among processing conditions, microstructure, and mechanical properties. We developed a machine learning framework trained on experimentally acquired, multi-source datasets covering polyethylene, polypropylene, and polybutene-1 prepared by compression molding, extrusion, and injection molding. Nine algorithms were systematically evaluated for predicting Young's modulus, elongation at break, and tensile strength. Among them, Random Forest and Extreme Gradient Boosting (XGB) delivered superior accuracy with R<sup>2</sup> > 0.80 for polypropylene and polybutene-1, effectively capturing nonlinear processing-structure-property correlations. Model interpretation revealed test temperature, sample thickness, and processing method as the most influential variables, consistent with established polymer physics. Furthermore, global models trained on fused multi-material datasets performed within 5% of material-specific models, demonstrating the reliability of data fusion for small-sample learning. The engineering stress-strain curve reconstruction using XGB achieved R<sup>2</sup> > 0.85, highlighting the framework’s robustness. This work establishes a data-driven route for understanding and predicting mechanical properties of polyolefins, offering quantitative insights toward accelerated polymer design and processing optimization.</div></div>","PeriodicalId":405,"journal":{"name":"Polymer","volume":"345 ","pages":"Article 129574"},"PeriodicalIF":4.5,"publicationDate":"2026-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145908234","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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

Viscoelastic strain recovery governs crack-tip opening dynamics of elastomers 粘弹性应变恢复控制弹性体裂纹尖端打开动力学

IF 4.5 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2026-01-07 DOI: 10.1016/j.polymer.2026.129564

Ayano Kozono , Thanh-Tam Mai , Kenji Urayama

This study explores the crack opening dynamics in Mode-I fracture of pre-stretched viscoelastic elastomer sheets under varying strain energy release rate (Γ). The degree of viscoelasticity was widely tuned by altering the mixing ratio of telechelic precursor chains and a tri-functional cross-linker, producing elastomers with different amounts of relaxation components such as dangling chains and finite clusters not incorporated into infinite networks. When Γ exceeds a critical threshold Γ∗, the crack velocity exhibits a sharp, order-of-magnitude increase—independent of viscoelasticity—similar to that observed in conventional elastic elastomers. A key difference, however, emerges in the crack-tip opening displacement (CTOD): while elastic elastomers maintain a nearly constant CTOD across the velocity jump, viscoelastic elastomers show a pronounced reduction. CTOD reflects the extent of shape recovery in the unloaded region behind the crack tip from the pre-stretched state. In viscoelastic elastomers, this recovery requires a characteristic relaxation time (τ_R). When crack propagation accelerates at Γ∗, the observation time for CTOD (t_obs) at the specimen center becomes much shorter than τ_R, leading to incomplete recovery and, consequently, reduced CTOD. Independent creep-recovery tests demonstrate that τ_R corresponds closely to the critical observation time (t_obs∗) at which CTOD begins to decrease from its fully opened state. These findings reveal a unique strain-retention effect during rapid crack propagation in viscoelastic solids, providing new insights into their fracture dynamics.

本研究探讨了不同应变能释放速率下预拉伸粘弹性弹性体片材i型断裂的裂纹张开动力学（Γ）。通过改变远旋前体链和三功能交联剂的混合比例，可以广泛调节粘弹性的程度，从而产生具有不同松弛成分的弹性体，如悬垂链和不包含在无限网络中的有限团簇。当Γ超过临界阈值Γ *时，裂纹速度表现出与粘弹性无关的急剧数量级增加，这与在常规弹性弹性体中观察到的情况相似。然而，在裂纹尖端张开位移（CTOD）方面出现了一个关键的区别：弹性弹性体在速度跳变过程中保持几乎恒定的CTOD，而粘弹性弹性体的裂纹尖端张开位移明显减小。CTOD反映了裂纹尖端后的卸载区域从预拉伸状态中恢复形状的程度。在粘弹性弹性体中，这种恢复需要一个特征松弛时间（τR）。当裂纹扩展速度在Γ *处加速时，试样中心的CTOD （tobs）观测时间比τR短得多，导致不完全恢复，从而降低了CTOD。独立蠕变恢复试验表明，τR与临界观测时间（tobs *）非常接近，此时CTOD开始从完全打开状态下降。这些发现揭示了粘弹性固体在快速裂纹扩展过程中独特的应变保留效应，为其断裂动力学提供了新的见解。

{"title":"Viscoelastic strain recovery governs crack-tip opening dynamics of elastomers","authors":"Ayano Kozono , Thanh-Tam Mai , Kenji Urayama","doi":"10.1016/j.polymer.2026.129564","DOIUrl":"10.1016/j.polymer.2026.129564","url":null,"abstract":"<div><div>This study explores the crack opening dynamics in Mode-I fracture of pre-stretched viscoelastic elastomer sheets under varying strain energy release rate (<em>Γ</em>). The degree of viscoelasticity was widely tuned by altering the mixing ratio of telechelic precursor chains and a tri-functional cross-linker, producing elastomers with different amounts of relaxation components such as dangling chains and finite clusters not incorporated into infinite networks. When <em>Γ</em> exceeds a critical threshold <em>Γ</em>∗, the crack velocity exhibits a sharp, order-of-magnitude increase—independent of viscoelasticity—similar to that observed in conventional elastic elastomers. A key difference, however, emerges in the crack-tip opening displacement (CTOD): while elastic elastomers maintain a nearly constant CTOD across the velocity jump, viscoelastic elastomers show a pronounced reduction. CTOD reflects the extent of shape recovery in the unloaded region behind the crack tip from the pre-stretched state. In viscoelastic elastomers, this recovery requires a characteristic relaxation time (<em>τ</em><sub>R</sub>). When crack propagation accelerates at <em>Γ</em>∗, the observation time for CTOD (<em>t</em><sub>obs</sub>) at the specimen center becomes much shorter than <em>τ</em><sub>R</sub>, leading to incomplete recovery and, consequently, reduced CTOD. Independent creep-recovery tests demonstrate that <em>τ</em><sub>R</sub> corresponds closely to the critical observation time (<em>t</em><sub>obs</sub>∗) at which CTOD begins to decrease from its fully opened state. These findings reveal a unique strain-retention effect during rapid crack propagation in viscoelastic solids, providing new insights into their fracture dynamics.</div></div>","PeriodicalId":405,"journal":{"name":"Polymer","volume":"345 ","pages":"Article 129564"},"PeriodicalIF":4.5,"publicationDate":"2026-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145956593","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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

In-Situ polyamide fibrillation in epoxidized natural rubber as an effective strategy for reinforcing natural rubber composites 环氧化天然橡胶中原位聚酰胺纤颤是增强天然橡胶复合材料的有效策略

IF 4.5 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2026-01-07 DOI: 10.1016/j.polymer.2026.129586

Yuze Wu, Kai Cai, Haobo Wang, Yu Cheng, Anjie Yang, Jie Feng

While numerous strategies have been developed to enhance the mechanical properties of rubber, there remains a notable scarcity of efficient, simple, and sustainable approaches. This study investigates the feasibility of using in-situ fibrillation of low-melting-point polyamide (LMPA) to reinforce epoxidized natural rubber (ENR), while simultaneously exploring ENR's potential as a compatibilizer to improve LMPA reinforcement in natural rubber (NR). The results indicate strong interfacial interactions and excellent compatibility in LMPA/ENR composites, whereas LMPA/NR blends show significant incompatibility. However, the incorporation of ENR as a compatibilizer effectively elevates the performance of NR-based systems to levels comparable with ENR-based composites. SEM observations demonstrate that LMPA undergoes in-situ fibrillation during melt blending with ENR, forming fibrillar structures that substantially enhance the matrix modulus compared to granular morphologies. TEM analysis further reveals that adding ENR to NR/LMPA composites produces a LMPA@ENR core-shell structure, which significantly improves stress transfer efficiency. With the addition of 30 phr LMPA, the moduli at 100 % (M₁₀₀) and 300 % elongation (M₃₀₀) increased from 0.86 MPa to 2.07 MPa (pure ENR) to 4.92 MPa and 9.81 MPa, representing remarkable improvements of 472.09 % and 393.91 %, respectively. This work demonstrates LMPA's unique capability to form in-situ microfibrils for rubber reinforcement and presents a novel strategy for developing high-performance rubber composites.

虽然已经开发了许多策略来提高橡胶的机械性能，但仍然缺乏有效，简单和可持续的方法。本研究探讨了原位纤颤法制备低熔点聚酰胺（LMPA）增强环氧化天然橡胶（ENR）的可行性，同时探讨了ENR作为增容剂改善天然橡胶（NR）中LMPA增强的潜力。结果表明，LMPA/ENR复合材料具有较强的界面相互作用和良好的相容性，而LMPA/NR共混物表现出明显的不相容性。然而，加入ENR作为相容剂有效地将nr基系统的性能提升到与ENR基复合材料相当的水平。SEM观察表明，LMPA在熔体与ENR共混过程中发生原位纤颤，形成纤维状结构，与颗粒形态相比，显著提高了基体模量。TEM分析进一步表明，在NR/LMPA复合材料中加入ENR可形成LMPA@ENR核壳结构，显著提高了应力传递效率。当添加30 phr LMPA时，100%伸长率（M100）和300%伸长率（M300）的模量分别从0.86 MPa和2.07 MPa（纯ENR）提高到4.92 MPa和9.81 MPa，分别提高了472.09%和393.91%。这项工作证明了LMPA在原位形成橡胶增强微原纤维的独特能力，并为开发高性能橡胶复合材料提供了一种新的策略。

{"title":"In-Situ polyamide fibrillation in epoxidized natural rubber as an effective strategy for reinforcing natural rubber composites","authors":"Yuze Wu, Kai Cai, Haobo Wang, Yu Cheng, Anjie Yang, Jie Feng","doi":"10.1016/j.polymer.2026.129586","DOIUrl":"10.1016/j.polymer.2026.129586","url":null,"abstract":"<div><div>While numerous strategies have been developed to enhance the mechanical properties of rubber, there remains a notable scarcity of efficient, simple, and sustainable approaches. This study investigates the feasibility of using in-situ fibrillation of low-melting-point polyamide (LMPA) to reinforce epoxidized natural rubber (ENR), while simultaneously exploring ENR's potential as a compatibilizer to improve LMPA reinforcement in natural rubber (NR). The results indicate strong interfacial interactions and excellent compatibility in LMPA/ENR composites, whereas LMPA/NR blends show significant incompatibility. However, the incorporation of ENR as a compatibilizer effectively elevates the performance of NR-based systems to levels comparable with ENR-based composites. SEM observations demonstrate that LMPA undergoes in-situ fibrillation during melt blending with ENR, forming fibrillar structures that substantially enhance the matrix modulus compared to granular morphologies. TEM analysis further reveals that adding ENR to NR/LMPA composites produces a LMPA@ENR core-shell structure, which significantly improves stress transfer efficiency. With the addition of 30 phr LMPA, the moduli at 100 % (M<sub>100</sub>) and 300 % elongation (M<sub>300</sub>) increased from 0.86 MPa to 2.07 MPa (pure ENR) to 4.92 MPa and 9.81 MPa, representing remarkable improvements of 472.09 % and 393.91 %, respectively. This work demonstrates LMPA's unique capability to form in-situ microfibrils for rubber reinforcement and presents a novel strategy for developing high-performance rubber composites.</div></div>","PeriodicalId":405,"journal":{"name":"Polymer","volume":"345 ","pages":"Article 129586"},"PeriodicalIF":4.5,"publicationDate":"2026-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145924023","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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

High-performance PVA hydrogels with high strength, fatigue resistance, and low hysteresis via high-temperature stretching-assisted post-rehydration 高性能的PVA水凝胶具有高强度，抗疲劳，低迟滞通过高温拉伸辅助后补液

IF 4.5 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2026-01-07 DOI: 10.1016/j.polymer.2025.129551

Lidan Zhang , Fuhui Chen , Jian Hu , Wenpeng Zhao , Shouke Yan

Polyvinyl alcohol (PVA) has emerged as a fundamental matrix material for constructing mechanically robust and fatigue-resistant hydrogels, owing to its unique combination of excellent biocompatibility, outstanding chemical stability, remarkable hydrophilicity, and cost-effectiveness. As physically cross-linked single-component systems, mechanical properties of PVA hydrogels are predominantly governed by two structural parameters: crystallinity and orientation of the crystallites. Herein, we propose a facile “high-temperature stretching-assisted post-rehydration” strategy to fabricate high-performance PVA hydrogels through simultaneous enhancement of crystallinity and crystalline alignment. Remarkably, the developed method successfully integrates multiple traditionally incompatible mechanical properties, including high tensile strength (30 MPa), exceptional fracture energy (22.4 kJ/m²), superior fatigue resistance (9100 J/m²), low hysteresis (8.3 %), and characteristic J-shaped stress-strain behavior.

聚乙烯醇（PVA）由于其独特的生物相容性、优异的化学稳定性、卓越的亲水性和成本效益，已成为构建机械坚固和抗疲劳水凝胶的基本基质材料。作为物理交联的单组分体系，PVA水凝胶的力学性能主要受结晶度和晶体取向两个结构参数的影响。在此，我们提出了一种简单的“高温拉伸辅助后再水化”策略，通过同时增强结晶度和晶体排列来制备高性能PVA水凝胶。值得注意的是，该方法成功地集成了多种传统上不相容的力学性能，包括高抗拉强度（30 MPa）、优异的断裂能（22.4 kJ/m2）、优异的抗疲劳性能（9100 J/m2）、低迟滞（8.3%）和特征的J形应力-应变行为。

{"title":"High-performance PVA hydrogels with high strength, fatigue resistance, and low hysteresis via high-temperature stretching-assisted post-rehydration","authors":"Lidan Zhang , Fuhui Chen , Jian Hu , Wenpeng Zhao , Shouke Yan","doi":"10.1016/j.polymer.2025.129551","DOIUrl":"10.1016/j.polymer.2025.129551","url":null,"abstract":"<div><div>Polyvinyl alcohol (PVA) has emerged as a fundamental matrix material for constructing mechanically robust and fatigue-resistant hydrogels, owing to its unique combination of excellent biocompatibility, outstanding chemical stability, remarkable hydrophilicity, and cost-effectiveness. As physically cross-linked single-component systems, mechanical properties of PVA hydrogels are predominantly governed by two structural parameters: crystallinity and orientation of the crystallites. Herein, we propose a facile “high-temperature stretching-assisted post-rehydration” strategy to fabricate high-performance PVA hydrogels through simultaneous enhancement of crystallinity and crystalline alignment. Remarkably, the developed method successfully integrates multiple traditionally incompatible mechanical properties, including high tensile strength (30 MPa), exceptional fracture energy (22.4 kJ/m<sup>2</sup>), superior fatigue resistance (9100 J/m<sup>2</sup>), low hysteresis (8.3 %), and characteristic J-shaped stress-strain behavior.</div></div>","PeriodicalId":405,"journal":{"name":"Polymer","volume":"345 ","pages":"Article 129551"},"PeriodicalIF":4.5,"publicationDate":"2026-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145924022","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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

The effect of chain extender symmetry, branching and hydrogen bonding capability on the morphology and mechanical properties of thermoplastic polyurethanes 扩链剂的对称、支化和氢键性能对热塑性聚氨酯形貌和力学性能的影响

IF 4.5 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2026-01-07 DOI: 10.1016/j.polymer.2026.129578

Simon A. Fawcett , Thomas S. Jackson , James A. Wilson , Jennifer C. Hughes , Alarqam Z. Tareq , Lewis R. Hart , Wayne Hayes , Andrew T. Slark

The chemical architecture of chain extenders within thermoplastic polyurethanes (TPUs) has a marked effect on material properties. To evaluate the structure-property relationships within linear TPUs, three different chain extenders with varying chemical structure (i.e. symmetry, branching and hydrogen bonding capability) were used in the synthesis of three low T_g semi-crystalline TPUs with low molecular weight (M_n = 18 kDa). These copolymers were compared to a non-chain extended reference. Results showed that the architecture of the chain extender dictated the degree of hard-soft microphase separation and therefore the mechanical properties. A TPU without chain extender (PU-NC) was a brittle hard-soft phase mixed material. Incorporation of the branched asymmetrical chain extender, 1,2-propanediol (PU-PD), also resulted in a phase mixed material which was mechanically weak with low adhesive properties (lap shear max. stress = 1.0 ± 0.1 MPa). The use of the symmetrical linear chain extender 1,4-butanediol (PU-BD) afforded a hard-soft phase separated copolymer where the mechanical and adhesive performance obtained was as expected for such low molecular weight TPUs (E = 72 ± 8 MPa, lap shear max. stress = 2.1 ± 0.4 MPa). The copolymer with a symmetrical bisurea diol chain extender (PU-BU) also exhibited a hard-soft phase separated morphology, but with much higher tensile (E = 210 ± 16 MPa) and adhesive properties (lap shear max. stress = 4.4 ± 0.1 MPa) as a result of strong bidentate urea hydrogen bonding. Incorporating these non-covalent interactions into the chain extender provides a route to superior mechanical performance for TPUs with low molecular weight.

热塑性聚氨酯（tpu）中扩链剂的化学结构对材料性能有显著影响。为了评价线性tpu内部的结构-性能关系，采用三种不同的扩链剂，分别具有不同的化学结构（即对称、分支和氢键能力），合成了三种低Tg低分子量（Mn = 18 kDa）的半晶tpu。将这些共聚物与非链扩展参考物进行了比较。结果表明，扩链剂的结构决定了软硬微相分离的程度，从而决定了其力学性能。不含扩链剂的TPU （PU-NC）是一种脆性硬-软相混合材料。支化不对称扩链剂1,2-丙二醇（PU-PD）的掺入也导致相混合材料力学性能弱，粘接性能低（搭接剪切最大值）。应力= 1.0±0.1 MPa)。使用对称线性扩链剂1,4-丁二醇（PU-BD），获得了一种硬-软相分离共聚物，其力学性能和粘接性能与这种低分子量tpu （E = 72±8 MPa, lap - shear max）的预期一致。应力= 2.1±0.4 MPa)。含有对称双脲二醇扩链剂（PU-BU）的共聚物也表现出硬-软相分离形态，但具有更高的拉伸性能（E = 210±16 MPa）和粘接性能（lap - shear max）。应力= 4.4±0.1 MPa)，这是由于双齿脲氢键作用较强。将这些非共价相互作用纳入扩链剂中，为低分子量tpu提供了优越的机械性能。

{"title":"The effect of chain extender symmetry, branching and hydrogen bonding capability on the morphology and mechanical properties of thermoplastic polyurethanes","authors":"Simon A. Fawcett , Thomas S. Jackson , James A. Wilson , Jennifer C. Hughes , Alarqam Z. Tareq , Lewis R. Hart , Wayne Hayes , Andrew T. Slark","doi":"10.1016/j.polymer.2026.129578","DOIUrl":"10.1016/j.polymer.2026.129578","url":null,"abstract":"<div><div>The chemical architecture of chain extenders within thermoplastic polyurethanes (TPUs) has a marked effect on material properties. To evaluate the structure-property relationships within linear TPUs, three different chain extenders with varying chemical structure (i.e. symmetry, branching and hydrogen bonding capability) were used in the synthesis of three low <em>T</em><sub>g</sub> semi-crystalline TPUs with low molecular weight (<em>M</em><sub>n</sub> = 18 kDa). These copolymers were compared to a non-chain extended reference. Results showed that the architecture of the chain extender dictated the degree of hard-soft microphase separation and therefore the mechanical properties. A TPU without chain extender (PU-NC) was a brittle hard-soft phase mixed material. Incorporation of the branched asymmetrical chain extender, 1,2-propanediol (PU-PD), also resulted in a phase mixed material which was mechanically weak with low adhesive properties (lap shear max. stress = 1.0 ± 0.1 MPa). The use of the symmetrical linear chain extender 1,4-butanediol (PU-BD) afforded a hard-soft phase separated copolymer where the mechanical and adhesive performance obtained was as expected for such low molecular weight TPUs (<em>E</em> = 72 ± 8 MPa, lap shear max. stress = 2.1 ± 0.4 MPa). The copolymer with a symmetrical bisurea diol chain extender (PU-BU) also exhibited a hard-soft phase separated morphology, but with much higher tensile (<em>E</em> = 210 ± 16 MPa) and adhesive properties (lap shear max. stress = 4.4 ± 0.1 MPa) as a result of strong bidentate urea hydrogen bonding. Incorporating these non-covalent interactions into the chain extender provides a route to superior mechanical performance for TPUs with low molecular weight.</div></div>","PeriodicalId":405,"journal":{"name":"Polymer","volume":"345 ","pages":"Article 129578"},"PeriodicalIF":4.5,"publicationDate":"2026-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145937521","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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

Design and fabrication of functionally graded Ba0.6Sr0.4TiO3/ Polyetheretherketone composites with tailored dielectric properties via fused deposition modeling 通过熔融沉积建模设计和制备具有定制介电性能的功能梯度Ba0.6Sr0.4TiO3/聚醚醚酮复合材料

IF 4.5 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2026-01-07 DOI: 10.1016/j.polymer.2026.129587

Shuhang Liu , Jianan Wang , Xin Xu , Xiaoyu Xu , Xiaoying Feng , Pengfei Wang , Lili Zhao , Jie Xu , Bin Yang , Feng Gao

This study presents a novel approach for fabricating Ba_0.6Sr_0.4TiO₃/Polyetheretherketone (BST/PEEK) composites with spatially graded dielectric properties using fused deposition modeling (FDM). To achieve localized property control, composites were engineered with gradient cylindrical cavities of varying diameters (1–4 mm). Experimental characterization demonstrated that the dielectric permittivity and its tunability under DC bias exhibited an inverse relationship with cavity size; permittivity decreased from 7.62 (1 mm cavities) to 5.45 (4 mm cavities), while tunability dropped from 18.71 % to 6.79 %. The effective medium theories (EMTs), including the Yamada model, Bruggeman model, Differential effective medium, etc., were successfully applied to predict the composite permittivity, showing strong agreement with experimental data (error <5 %). By strategically arranging these cavity designs, composites with pre-programmed permittivity gradients were realized. The potential of this tailored substrate was demonstrated through a tunable multi-frequency antenna, which achieved a shift in central operating frequency (2.7–10 %) under DC bias across 5G, satellite, and industrial IoT bands (3.0, 3.3, and 3.7 GHz). This work effectively integrates theoretical modeling with additive manufacturing for developing functionally graded composites for advanced RF and bioelectronic applications.

本研究提出了一种利用熔融沉积模型（FDM）制备具有空间梯度介电性能的Ba0.6Sr0.4TiO3/聚醚醚酮（BST/PEEK）复合材料的新方法。为了实现局部性能控制，复合材料被设计成不同直径（1-4毫米）的梯度圆柱形空腔。实验表征表明，介质介电常数及其在直流偏置下的可调性与空腔尺寸呈反比关系；介电常数从7.62 （1 mm空腔）下降到5.45 （4 mm空腔），可调性从18.71%下降到6.79%。利用有效介质理论（EMTs），包括Yamada模型、Bruggeman模型、差分有效介质等，成功地预测了复合介电常数，与实验数据吻合较好（误差<； 5%）。通过有策略地排列这些腔体设计，实现了具有预编程介电常数梯度的复合材料。通过可调谐多频天线展示了这种定制基板的潜力，该天线在5G、卫星和工业物联网频段（3.0、3.3和3.7 GHz）的直流偏置下实现了中心工作频率（2.7 - 10%）的偏移。这项工作有效地将理论建模与增材制造相结合，以开发用于先进射频和生物电子应用的功能梯度复合材料。

{"title":"Design and fabrication of functionally graded Ba0.6Sr0.4TiO3/ Polyetheretherketone composites with tailored dielectric properties via fused deposition modeling","authors":"Shuhang Liu , Jianan Wang , Xin Xu , Xiaoyu Xu , Xiaoying Feng , Pengfei Wang , Lili Zhao , Jie Xu , Bin Yang , Feng Gao","doi":"10.1016/j.polymer.2026.129587","DOIUrl":"10.1016/j.polymer.2026.129587","url":null,"abstract":"<div><div>This study presents a novel approach for fabricating Ba<sub>0.6</sub>Sr<sub>0.4</sub>TiO<sub>3</sub>/Polyetheretherketone (BST/PEEK) composites with spatially graded dielectric properties using fused deposition modeling (FDM). To achieve localized property control, composites were engineered with gradient cylindrical cavities of varying diameters (1–4 mm). Experimental characterization demonstrated that the dielectric permittivity and its tunability under DC bias exhibited an inverse relationship with cavity size; permittivity decreased from 7.62 (1 mm cavities) to 5.45 (4 mm cavities), while tunability dropped from 18.71 % to 6.79 %. The effective medium theories (EMTs), including the Yamada model, Bruggeman model, Differential effective medium, etc., were successfully applied to predict the composite permittivity, showing strong agreement with experimental data (error <5 %). By strategically arranging these cavity designs, composites with pre-programmed permittivity gradients were realized. The potential of this tailored substrate was demonstrated through a tunable multi-frequency antenna, which achieved a shift in central operating frequency (2.7–10 %) under DC bias across 5G, satellite, and industrial IoT bands (3.0, 3.3, and 3.7 GHz). This work effectively integrates theoretical modeling with additive manufacturing for developing functionally graded composites for advanced RF and bioelectronic applications.</div></div>","PeriodicalId":405,"journal":{"name":"Polymer","volume":"345 ","pages":"Article 129587"},"PeriodicalIF":4.5,"publicationDate":"2026-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145924025","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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

Predicting fracture toughness of double network hydrogel via monotonic loading test 通过单调加载试验预测双网状水凝胶的断裂韧性

IF 4.5 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2026-01-06 DOI: 10.1016/j.polymer.2026.129573

Jiapeng You , Zishun Liu

Double network (DN) hydrogels exhibit significant fracture toughness due to their unique toughening mechanisms. To gain a deeper understanding of these mechanisms during damage, it is crucial to explore the fracture toughness of DN gels post-damage. Although prior research has primarily focused on measuring the fracture toughness of damaged DN gels, the correlation between fracture toughness and damage remains largely unexplored. This study presents a method to predict the fracture toughness of DN gels following any degree of pre-damage. Firstly, we perform tearing tests on DN gels with various pre-damage levels to determine their fracture toughness and dissipated energy density distribution. We then establish a correlation between dissipated energy density distribution and monotonic loading. Consequently, the fracture toughness of DN gels following any degree of pre-damage can be estimated using the dissipated energy density distribution through a single monotonic loading test and a simple tearing test on the as-prepared DN gel specimen. Additionally, we propose a novel parameter to define the feature size of the damage zone in DN gels, which can also be determined by the same testing method. This study provides a quantitative framework linking pre-damage to the fracture toughness of DN gels. The results offer insights into the evolution of damage and toughening mechanisms, and they provide design principles for developing the next generation of advanced soft materials.

双网（DN）水凝胶由于其独特的增韧机制而表现出显著的断裂韧性。为了在损伤过程中更深入地了解这些机制，研究损伤后DN凝胶的断裂韧性至关重要。虽然之前的研究主要集中在测量受损DN凝胶的断裂韧性，但断裂韧性与损伤之间的相关性仍未得到充分探讨。本研究提出了一种预测DN凝胶在任何程度预损伤后断裂韧性的方法。首先，我们对不同预损伤程度的DN凝胶进行撕裂试验，确定其断裂韧性和耗散能量密度分布。然后，我们建立了耗散能量密度分布与单调载荷之间的相关性。因此，通过对制备好的DN凝胶试样进行单次单调加载试验和简单撕裂试验，利用耗散能量密度分布可以估计任意程度预损伤后DN凝胶的断裂韧性。此外，我们提出了一个新的参数来定义DN凝胶中损伤区域的特征尺寸，该参数也可以通过相同的测试方法确定。该研究提供了一个定量框架，将预损伤与DN凝胶的断裂韧性联系起来。该结果为损伤和增韧机制的演变提供了见解，并为开发下一代先进软材料提供了设计原则。

{"title":"Predicting fracture toughness of double network hydrogel via monotonic loading test","authors":"Jiapeng You , Zishun Liu","doi":"10.1016/j.polymer.2026.129573","DOIUrl":"10.1016/j.polymer.2026.129573","url":null,"abstract":"<div><div>Double network (DN) hydrogels exhibit significant fracture toughness due to their unique toughening mechanisms. To gain a deeper understanding of these mechanisms during damage, it is crucial to explore the fracture toughness of DN gels post-damage. Although prior research has primarily focused on measuring the fracture toughness of damaged DN gels, the correlation between fracture toughness and damage remains largely unexplored. This study presents a method to predict the fracture toughness of DN gels following any degree of pre-damage. Firstly, we perform tearing tests on DN gels with various pre-damage levels to determine their fracture toughness and dissipated energy density distribution. We then establish a correlation between dissipated energy density distribution and monotonic loading. Consequently, the fracture toughness of DN gels following any degree of pre-damage can be estimated using the dissipated energy density distribution through a single monotonic loading test and a simple tearing test on the as-prepared DN gel specimen. Additionally, we propose a novel parameter to define the feature size of the damage zone in DN gels, which can also be determined by the same testing method. This study provides a quantitative framework linking pre-damage to the fracture toughness of DN gels. The results offer insights into the evolution of damage and toughening mechanisms, and they provide design principles for developing the next generation of advanced soft materials.</div></div>","PeriodicalId":405,"journal":{"name":"Polymer","volume":"345 ","pages":"Article 129573"},"PeriodicalIF":4.5,"publicationDate":"2026-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145903136","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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

Tuning the cross-linking of phenolic aerogel by templates and solvents: a molecular dynamics study 通过模板和溶剂调节酚醛气凝胶的交联：分子动力学研究

IF 4.5 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2026-01-06 DOI: 10.1016/j.polymer.2026.129565

Lei Chen , Congyan Hu , Xue Nie , Zixuan Lei , Zhenhua Luo , Pingxia Zhang , Tong Zhao

Understanding the microscopic mechanisms of pore formation is essential for designing high-performance phenolic resin (PF) aerogels. In this work, a reaction-radius-driven Perl algorithm was developed to construct three-dimensional crosslinked PF networks, and molecular dynamics simulations were employed to investigate the roles of PMMA templates and solvents during reaction-induced phase separation (RIPS). The results reveal that the templates jointly regulate chain mobility and molecular interactions, thereby controlling pore size, morphology, and distribution of PF. Higher PMMA content enlarges pore size by strengthening PF-PMMA interactions and weakening PF-PF network constraints. Notably, an optimal PMMA chain length (DP60) was identified, at which relatively weaker PF-PMMA interfacial interactions promote PMMA self-aggregation, leading to the maximum pore size and FFV. Solvent molecules preferentially interact with both PF and PMMA, weakening direct PF-PMMA interactions and promoting hierarchical pore formation. This study provides molecular-level insights into how templating agents regulate aerogel architecture and offers a framework for rationally designing PF aerogels with tailored porosity.

了解孔隙形成的微观机制对于设计高性能酚醛树脂（PF）气凝胶至关重要。在这项工作中，开发了一个反应半径驱动的Perl算法来构建三维交联PF网络，并采用分子动力学模拟来研究PMMA模板和溶剂在反应诱导相分离（RIPS）中的作用。结果表明，模板通过调控链迁移率和分子间相互作用，控制了PF的孔径、形态和分布，PMMA含量的增加通过增强PF-PMMA相互作用和减弱PF-PF网络约束来扩大孔径。值得注意的是，我们确定了PMMA的最佳链长（DP60），在DP60时，相对较弱的PF-PMMA界面相互作用促进PMMA自聚集，从而导致最大的孔径和FFV。溶剂分子优先与PF和PMMA相互作用，削弱PF-PMMA直接相互作用，促进分层孔隙形成。这项研究为模板剂如何调节气凝胶结构提供了分子水平的见解，并为合理设计具有定制孔隙度的PF气凝胶提供了框架。

{"title":"Tuning the cross-linking of phenolic aerogel by templates and solvents: a molecular dynamics study","authors":"Lei Chen , Congyan Hu , Xue Nie , Zixuan Lei , Zhenhua Luo , Pingxia Zhang , Tong Zhao","doi":"10.1016/j.polymer.2026.129565","DOIUrl":"10.1016/j.polymer.2026.129565","url":null,"abstract":"<div><div>Understanding the microscopic mechanisms of pore formation is essential for designing high-performance phenolic resin (PF) aerogels. In this work, a reaction-radius-driven Perl algorithm was developed to construct three-dimensional crosslinked PF networks, and molecular dynamics simulations were employed to investigate the roles of PMMA templates and solvents during reaction-induced phase separation (RIPS). The results reveal that the templates jointly regulate chain mobility and molecular interactions, thereby controlling pore size, morphology, and distribution of PF. Higher PMMA content enlarges pore size by strengthening PF-PMMA interactions and weakening PF-PF network constraints. Notably, an optimal PMMA chain length (DP60) was identified, at which relatively weaker PF-PMMA interfacial interactions promote PMMA self-aggregation, leading to the maximum pore size and FFV. Solvent molecules preferentially interact with both PF and PMMA, weakening direct PF-PMMA interactions and promoting hierarchical pore formation. This study provides molecular-level insights into how templating agents regulate aerogel architecture and offers a framework for rationally designing PF aerogels with tailored porosity.</div></div>","PeriodicalId":405,"journal":{"name":"Polymer","volume":"345 ","pages":"Article 129565"},"PeriodicalIF":4.5,"publicationDate":"2026-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145924024","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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最新文献