Polymer最新文献_第10页

Effects of geometric discontinuities on tensile fatigue deterioration and life estimation in additively manufactured polylactic acid (PLA) parts 几何不连续对增材制造聚乳酸（PLA）零件拉伸疲劳劣化和寿命估计的影响

IF 4.5 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2026-03-06 Epub Date: 2026-02-05 DOI: 10.1016/j.polymer.2026.129706

Mahsima Seifollahi, Mohammad Zaman Kabir, Sara Golbabapour

In this study, an integrated experimental–analytical framework was employed to investigate the effects of geometric imperfections on the static and fatigue behaviour of 3D-printed polylactic acid (PLA) specimens. The specimens were fabricated using Fused Deposition Modeling (FDM) with YZ orientation and a concentric infill pattern. Experimental results showed that a central hole with a stress concentration factor of 1.95 resulted in approximately 17% shorter fatigue life compared to edge-notched specimens. Notches and holes with a 2 mm radius yielded fatigue notch factors of 1.12 and 1.15, respectively, emphasizing the dominant influence of process-induced internal defects on fatigue damage evolution. To determine the notch geometry that can override the effect of internal defects on fatigue behaviour, the Theory of Critical Distance (TCD) coupled with numerical models was used to estimate the fatigue notch factor. In the numerical simulations, the internal porosity of the 3D-printed samples was taken into account to capture the interaction between notches and inherent defects. The analysis identified a notch aspect ratio of 0.25 as critical, exhibiting the highest fatigue notch factor of 1.59. Then, crack growth behaviour was monitored using Digital Image Correlation (DIC) and analysed through the Paris law to determine material constants. Fatigue life was subsequently estimated using a defect-based approach for 3D-printed PLA, explicitly accounting for process-induced internal defects.

在这项研究中，采用了一个集成的实验分析框架来研究几何缺陷对3d打印聚乳酸（PLA）样品的静态和疲劳行为的影响。采用YZ取向和同心填充模式的熔融沉积模型（FDM）制备样品。试验结果表明，中心孔的应力集中系数为1.95，与边缘缺口相比，中心孔的疲劳寿命缩短了约17%。半径为2mm的缺口和孔的疲劳缺口系数分别为1.12和1.15，强调了工艺诱导的内部缺陷对疲劳损伤演化的主导影响。为了确定能够覆盖内部缺陷对疲劳行为影响的缺口几何形状，采用临界距离理论（TCD）与数值模型相结合的方法估计了疲劳缺口因子。在数值模拟中，考虑了3d打印样品的内部孔隙率，以捕捉缺口和固有缺陷之间的相互作用。分析确定缺口长径比为0.25为临界值，显示出最高的疲劳缺口系数为1.59。然后利用数字图像相关（DIC）技术监测裂纹扩展行为，并利用Paris定律进行分析，确定材料常数。随后，使用基于缺陷的方法对3d打印PLA进行疲劳寿命估计，明确考虑了工艺引起的内部缺陷。

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引用次数: 0

Impact of amino functionalization on gelation properties of random terpolymer of oligo(ethylene glycol) methacrylates in water and physiological media 氨基功能化对低聚（乙二醇）甲基丙烯酸酯无规三元共聚物在水和生理介质中胶凝性能的影响

IF 4.5 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2026-03-06 Epub Date: 2026-01-29 DOI: 10.1016/j.polymer.2026.129652

D. Lipowska-Kur , P. Groch , Ł. Otulakowski , K. Filipek , K. Jelonek , A. Utrata-Wesołek

Thermoreversible gels (thermogels) are formed when solutions of thermoresponsive polymers transition from a low-viscosity liquid state to a gel state upon exceeding the gelation temperature (T_GEL). This property makes them attractive materials for a wide range of biomedical applications, including tissue engineering and drug delivery. While the gelation mechanism of block copolymers containing hydrophilic and hydrophobic segments are well understood, the ability of random copolymers, particularly those containing thermoresponsive units, to form stable gels is still not well established. In this work, we explore the gelation behavior of random copolymers based on oligo(ethylene glycol) methacrylates, focusing on the impact of amino functional groups studied in their ammonium and amine forms, and directly comparing them to non-functionalized polymer. As comonomers, oligo(ethylene glycol) methacrylate (O; M_n = 300 g/mol), di(ethylene glycol) methacrylate (D) and 2-aminoethyl methacrylate hydrochloride, introducing amino groups (in A⁽⁺⁾ NH₃⁺ and A NH₂ form), were used. The gelation behavior of the resulting copolymers was influenced by the presence of amine groups, their ionization state and the type of medium (water or PBS). Both the non-functionalized copolymer P(OD) and the amino-functionalized copolymer P(AOD) formed thermogels in water and PBS, whereas the ammonium-functionalized copolymer P(A⁽⁺⁾OD) exhibited gelation only in PBS. Moreover, the P(AOD) gel demonstrated superior mechanical strength and a more stable polymer network compared with the P(OD) gel, indicating a beneficial effect of amino groups on the properties of thermogelling materials. In addition, the amine-functionalized copolymer was found to be non-toxic, making the obtained materials particularly promising for biomedical applications.

热可逆凝胶（热凝胶）是当热响应性聚合物的溶液在超过凝胶化温度（TGEL）后从低粘度液态转变为凝胶态时形成的。这种特性使它们成为广泛的生物医学应用的有吸引力的材料，包括组织工程和药物输送。虽然含有亲水和疏水段的嵌段共聚物的凝胶机制已经被很好地理解，但随机共聚物，特别是那些含有热响应单元的共聚物，形成稳定凝胶的能力仍然没有很好地确定。在这项工作中，我们探索了基于低聚（乙二醇）甲基丙烯酸酯的无规共聚物的凝胶行为，重点研究了氨基官能团在其铵态和胺态中的影响，并直接将它们与非官能团聚合物进行了比较。以低聚（乙二醇）甲基丙烯酸酯（O; Mn = 300 g/mol）、二（乙二醇）甲基丙烯酸酯(D)和2-氨基甲基丙烯酸乙酯盐酸盐为共聚单体，引入氨基（以A(+) NH3+和A NH2形式）。所得共聚物的凝胶行为受胺基的存在、它们的电离状态和介质类型（水或PBS）的影响。非功能化共聚物P（OD）和氨基功能化共聚物P（AOD）在水和PBS中均形成热凝胶，而氨功能化共聚物P（A(+)OD）仅在PBS中形成凝胶。此外，与P（OD）凝胶相比，P（AOD）凝胶表现出更好的机械强度和更稳定的聚合物网络，这表明氨基对热凝胶材料的性能有有益的影响。此外，胺功能化共聚物被发现是无毒的，使所获得的材料在生物医学应用方面特别有前景。

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引用次数: 0

Molecular dynamics study on the formation of the interface between low-density polyethylene and cross-linked polyethylene 低密度聚乙烯与交联聚乙烯界面形成的分子动力学研究

IF 4.5 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2026-03-06 Epub Date: 2026-02-02 DOI: 10.1016/j.polymer.2026.129696

Chuxuan Chen, Zhaoyi Liu, Chaoqun Liu, Wei Yang, Guoqi Ma, Jiaping Pan, Yang Lv, Jinghui Gao, Li Yin

Exploring the interfacial behavior between different polymers is a hot issue in macromolecular blend materials. This paper takes low-density polyethylene (LDPE), cross-linked polyethylene (XLPE) and dicumyl peroxide (DCP) as models to investigate the interface formation process of different polymers and the diffusion behavior of small molecules by molecular dynamics simulation method using Consistent-Valence Force Field (CVFF) force field. The results reveal that interface between LDPE and XLPE forms through the penetration of linear polymer chains to cross-linked polymer chains, and van der Waals potential is the main driving attractive force. Temperature, pressure, and polymer network structure were found to have significantly influence the interface formation process. Additionally, DCP can introduce corss-linking structures to interface in theroy, the mobility of DCP in XLPE and LDPE were investigated and found that the diffusion coefficients of DCP in XLPE is only 1%–8% campring to that in LDPE. This study contributes to a further understanding of the interfacial formation mechanism of LDPE/XLPE blends.

研究不同聚合物之间的界面行为是高分子共混材料研究的热点问题。本文以低密度聚乙烯（LDPE）、交联聚乙烯（XLPE）和过氧化二氨基苯（DCP）为模型，采用一致价力场（CVFF）力场的分子动力学模拟方法，研究了不同聚合物的界面形成过程和小分子的扩散行为。结果表明，LDPE和XLPE之间的界面是通过线性聚合物链向交联聚合物链的渗透形成的，范德华势是主要的驱动引力。发现温度、压力和聚合物网络结构对界面形成过程有显著影响。DCP在XLPE和LDPE中的迁移率研究发现，DCP在XLPE中的扩散系数仅为LDPE中的1% ~ 8%。本研究有助于进一步了解LDPE/XLPE共混体系的界面形成机制。

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引用次数: 0

Temperature-responsive hyperbranched block copolymers via RAFT self-condensing vinyl polymerization RAFT自缩聚法制备温度响应型超支化嵌段共聚物

IF 4.5 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2026-03-06 Epub Date: 2026-02-03 DOI: 10.1016/j.polymer.2026.129699

Brett McLeland, Dean Afsar, Ayesha Imiya Mudiyanselage, Patricia R. Calvo

Stimuli-responsive polymers that undergo sharp transitions in aqueous solution are of broad interest for drug delivery, sensing, and self-assembly. Here we report the synthesis of hyperbranched poly(N-isopropylacrylamide)-b-poly(N,N-dimethylacrylamide) (HB-PNIPAM-b-PDMA) block copolymers via reversible addition–fragmentation chain transfer (RAFT)-mediated self-condensing vinyl polymerization (SCVP) of well-defined macro chain-transfer monomers (macro-CTMs). PNIPAM and PDMA precursors were prepared with high end-group fidelity and converted to macro-CTMs, enabling hyperbranched chain extensions alongside linear and random analogues for systematic comparison. All polymerizations proceeded to high conversion, and the degree of branching was tunable with monomer feed and precursor length. Thermoresponsive behavior was strongly influenced by architecture. Linear block copolymers exhibited composition-dependent cloud points between 48 and 67 °C, while random copolymers showed transitions ∼10 °C higher than their block counterparts. In contrast, hyperbranched copolymers displayed broadened and shifted transitions, with cloud points spanning ∼31.5 °C to >80 °C depending on composition, degree of polymerization, and macro-CTM identity. Dynamic light scattering confirmed thermal aggregation above the transition. These results establish branching as a powerful design parameter for tuning the location and breadth of thermal transitions beyond what is achievable with linear copolymers, offering new opportunities for engineering responsive assemblies with tailored properties.

在水溶液中经历急剧转变的刺激响应聚合物对药物传递，传感和自组装具有广泛的兴趣。在这里，我们报道了通过可逆加成-裂解链转移（RAFT）介导的乙烯基自缩合聚合（SCVP）合成超支化聚（N-异丙基丙烯酰胺）-b-聚（N，N-二甲基丙烯酰胺）（HB-PNIPAM-b-PDMA）嵌段共聚物的方法。PNIPAM和PDMA前体以高端基保真度制备，并转化为宏观ctms，使超支链扩展与线性和随机类似物一起进行系统比较。所有的聚合都进行了高转化，分支的程度是可调的单体投料和前驱体长度。热响应行为受到建筑结构的强烈影响。线性嵌段共聚物在48 ~ 67°C之间表现出组分依赖的云点，而随机共聚物的跃迁比嵌段共聚物高~ 10°C。相比之下，超支化共聚物表现出展宽和移位的过渡，云点跨越~ 31.5°C至>；80°C，具体取决于组成、聚合程度和宏观ctm同一性。动态光散射证实了跃迁上方的热聚集。这些结果确立了分支作为一个强大的设计参数，用于调整热转变的位置和宽度，而不是线性共聚物所能实现的，为具有定制性能的工程响应组件提供了新的机会。

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引用次数: 0

Green engineering of water-insoluble PVA/PAA nanofiber respiratory membranes for efficient particulate matter filtration with low pressure drop 水不溶性PVA/PAA纳米纤维呼吸膜的绿色工程，高效低压降颗粒物过滤

IF 4.5 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2026-03-06 Epub Date: 2026-01-22 DOI: 10.1016/j.polymer.2026.129634

Ashraful Islam , Sudip Kumar Lahiri , Md. Akil Akhter , Muhammad Imran , Dong Mengmeng , Yanbo Liu

Air pollution is a major concern due to rising particulate matter (PM) levels, requiring efficient filtration technologies for respiratory protection, and integrating eco-friendly fabrication methods further enhances environmental sustainability. We report water-insoluble nanofibrous membranes that combine high filtration efficiency (FE) with a low pressure drop (ΔP) for use in such masks. Using 18 % (w/v) polyvinyl alcohol (PVA) and polyacrylic acid (PAA) solutions in water, we electrospun four types of nanofiber membranes under optimised conditions (25 kV, 20 cm, 25 °C, 50 % RH). These included a pure PVA membrane and three PVA/PAA (60/40 wt%) composite membranes containing PAA of 3 kDa (NFM-1), 50 kDa (NFM-2), and both 3 kDa and 50 kDa (NFM-3). To induce crosslinking, all membranes were heat-treated at 100–160 °C for 25 min. Filtration tests showed that NFM-2 heat-treated at 140 °C achieved ∼99 % FE for particles ≥0.5 μm, with a ΔP of only 48 ± 1 Pa. Scanning electron microscopy (SEM) revealed smooth fibers with an average diameter of ∼192 nm and 59 % porosity for NFM-2. Fourier transform infrared (FTIR) spectroscopy confirmed the formation of ester linkages (–CO–O–R) at ≥120 °C between PVA and PAA, indicating successful thermal crosslinking and improved stability. After crosslinking, NFM-2 also exhibited a water contact angle (θ) of ∼90° and retained 100 % of its weight after immersion in 70 °C water, demonstrating complete water insolubility. The nanofiber membranes were further integrated with polypropylene (PP) spunbond and meltblown nonwovens in multilayer assemblies (up to four layers) to evaluate composite filter performance. This water-based, organic-solvent-free electrospinning process offers a green approach to producing high-performance respiratory filters.

由于颗粒物（PM）水平的上升，空气污染是一个主要问题，需要有效的过滤技术来保护呼吸，而整合环保的制造方法进一步提高了环境的可持续性。我们报道了一种结合了高过滤效率（FE）和低压降（ΔP）的水不溶性纳米纤维膜，用于这种口罩。我们使用18% （w/v）的聚乙烯醇（PVA）和聚丙烯酸（PAA）水溶液，在优化条件（25 kV, 20 cm, 25°C, 50% RH）下静电纺丝四种类型的纳米纤维膜。其中包括纯PVA膜和三种PVA/PAA （60/40 wt.%）复合膜，其中PAA为3 kDa (NFM-1), 50 kDa (NFM-2)，以及3 kDa和50 kDa （NFM-3）。为了诱导交联，所有膜在100-160°C下热处理25分钟。过滤试验表明，对于≥0.5 μm的颗粒，经过140℃热处理的NFM-2在ΔP仅为48±1 Pa时获得了~ 99%的FE。扫描电子显微镜显示光滑的纤维，平均直径为~ 192 nm， NFM-2的孔隙率为59%。傅里叶变换红外光谱（FTIR）证实PVA和PAA在≥120℃时形成酯键（-C = O-O-R），表明热交联成功，稳定性提高。交联后，NFM-2的水接触角（θ）为~ 90°，在70℃水中浸泡后仍能保持100%的重量，表现出完全的水不溶性。纳米纤维膜进一步与聚丙烯（PP）纺粘和熔喷非织造布在多层组件（多达四层）中集成，以评估复合过滤性能。这种水基、无有机溶剂的静电纺丝工艺为生产高性能呼吸过滤器提供了一种绿色方法。

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引用次数: 0

Highly efficient H2O2 photosynthesis coupled with benzylamine oxidation catalyzed by donor-acceptor type vinylene-linked covalent organic frameworks 用乙烯-受体共价有机框架催化H2O2与苯胺氧化的高效光合作用

IF 4.5 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2026-03-06 Epub Date: 2026-01-28 DOI: 10.1016/j.polymer.2026.129671

Shujie Qiao, Machao Wang, Jun Wang, Mingshuan Yang, Zhiyong Guo, Hongbing Zhan

Photocatalytic hydrogen peroxide (H₂O₂) production is a safe, economical and environmentally friendly method to convert solar energy into storable chemical energy. However, the slow water oxidation process derived from the photogenerated valence holes is one of the main obstacles for the H₂O₂ generation. The abovementioned dilemma can be resolved by consuming holes with sacrificial agent, e.g. benzylamine. In this paper, two vinylene-linked covalent organic frameworks (denoted as TMBP-1 and TMBP-2) with different donor-acceptor (D-A) strengths were synthesized. The constructed D-A architecture promoted the intramolecular charge transfer, which bolstered their corresponding photocatalytic performance. Impressively, when TMBP-2 adopted as the photocatalyst and air employed as the sole oxidant, highly efficient benzylamine coupling yield (>99.9 %) with a high H₂O₂ production up to 6.3 mmol g⁻¹ h⁻¹ can be obtained within 5 h under ambient conditions. Generally, this work provided a green pathway for the photocatalytic H₂O₂ production together with the manufacture of high value-added chemical intermediates.

光催化过氧化氢（H2O2）生产是一种安全、经济、环保的将太阳能转化为可储存的化学能的方法。然而，由光生成的价空穴引起的缓慢的水氧化过程是H2O2生成的主要障碍之一。上述困境可通过用牺牲剂（如苄胺）消耗孔洞来解决。本文合成了两种不同给受体（D-A）强度的乙烯连接共价有机框架（分别为TMBP-1和TMBP-2）。所构建的D-A结构促进了分子内电荷转移，从而增强了相应的光催化性能。令人印象深刻的是，当采用TMBP-2作为光催化剂，空气作为唯一氧化剂时，在环境条件下，5 h内可获得高效的苄胺偶联率（> 99.9%）， H2O2产量高达6.3 mmol g−1 h−1。总的来说，这项工作为光催化生产H2O2以及制造高附加值的化学中间体提供了一条绿色途径。

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引用次数: 0

Preparation of curcumin-loaded microparticles from star-shaped poly(lactic acid) stereo-complex 星形聚乳酸立体配合物制备载姜黄素微粒子

IF 4.5 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2026-03-06 Epub Date: 2026-02-02 DOI: 10.1016/j.polymer.2026.129695

Ayane Kawamura , Tsutomu Ishihara , Masanori Terasaki , Tomohiro Sago , Tadashi Tsukamoto , Yuji Shibasaki

The development of new biocompatible and biodegradable microparticles offering longer sustained drug release and greater stability than existing systems remains critical for subcutaneous injections. In this study, new microparticles based on a polylactide (PLA) stereo-complex (scPLA) stabilized with stearyl poly(ethylene glycol) (stPEG) were prepared. Curcumin, as a carrier drug, was encapsulated inside the prepared scPLA microparticles using the solution mixing method. Optical PLA isomers were prepared to enhance the loading capacity using mannose as a polyfunctional initiator, and scPLA samples were prepared via solution precipitation using the corresponding isomers. Varying the molecular weights and combinations of the isomers yielded scPLA microparticles with sizes ranging from 1.0 to 2.2 μm. These particles exhibited a single melting point (T_m) at approximately 215 °C, confirming the absence of PLA crystals (T_m = 150 °C). The desired curcumin-containing scPLA microparticles were successfully prepared by co-introducing curcumin and stPEG in the solution, with the maximum curcumin loading capacity reaching 14 wt%. scPLA microparticles loaded with curcumin showed significantly superior sustained release properties compared to nanoparticles composed of well-known mPEG-PLA copolymers also loaded with curcumin. This indicates that the highly stable crystalline structure of scPLA enabled the long-term drug release.

开发新的生物相容性和可生物降解的微颗粒，提供比现有系统更持久的药物释放和更大的稳定性，对于皮下注射仍然至关重要。在本研究中，制备了以硬脂酰聚乙二醇（stPEG）稳定的聚乳酸（PLA）立体配合物（scPLA）为基础的新型微颗粒。将姜黄素作为载体药物，采用溶液混合的方法包被在所制备的聚乳酸微粒中。以甘露糖为多能引发剂制备PLA光学异构体以提高负载能力，并利用相应的异构体通过溶液沉淀法制备scPLA样品。改变分子质量和同分异构体的组合可以得到尺寸在1.0 ~ 2.2 μm之间的scPLA微粒。这些颗粒在大约215°C时表现出单一熔点（Tm），证实不存在PLA晶体（Tm = 150°C）。通过在溶液中引入姜黄素和stPEG，成功制备了所需的含姜黄素的scPLA微粒子，其最大姜黄素负载量达到14wt %。与同样含有姜黄素的mPEG-PLA共聚物组成的纳米颗粒相比，载姜黄素的聚乳酸微颗粒具有显著的缓释性能。这表明scPLA高度稳定的晶体结构使其能够长期释放药物。

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引用次数: 0

Key determinants of hydrolytic stability of PLA/PBS blend fibers: The role of aromatic sulfonate derivative and carbodiimide PLA/PBS共混纤维水解稳定性的关键决定因素：芳香磺酸盐衍生物和碳二亚胺的作用

IF 4.5 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2026-03-06 Epub Date: 2026-02-04 DOI: 10.1016/j.polymer.2026.129669

Young Kwang Kim , Hye-Jin Seo , Seong Hui Hong , Chang-Hun Lee , Ik Sung Choi , Hyun Woo Song , Sang Kyoo Lim

The hydrolytic stability of poly (lactic acid) (PLA)/poly (butylene succinate) (PBS) blend fibers was systematically investigated by incorporating an aromatic sulfonate derivative (nucleating agent, N) and carbodiimide (anti-hydrolysis agent, Anti-H). Neat PLA/PBS blend fibers (3 wt% PBS) retained only ∼53.9% of their initial tensile strength after hydrolysis, whereas fibers containing both the nucleating agent (N) and anti-hydrolysis agent (Anti-H) preserved up to 97.2% of their initial strength. DSC and 2D-WAXD analyses showed that N selectively promoted the development and retention of the PLA (203) crystalline reflection, accompanied by enhanced crystallinity and molecular orientation along the PLA (200)/(110) planes. 1D-WAXD demonstrated that the intensity ratio of PLA (203) to PLA (200)/(110) reflections correlates with hydrolytic retention following a Boltzmann-type sigmoidal relationship, with a critical threshold x₀ ≈ 0.227. Time-dependent FTIR and XPS analyses demonstrated that Anti-H effectively capped the terminal –COOH groups, suppressing autocatalytic chain scission and providing complementary chemical stabilization. Hydrolysis decreased –COOH and –CO functional groups, while the H-bonded –OH increased. Correlation analysis indicated that changes in –CO most strongly influenced tensile retention. SEM observations revealed smooth fiber surfaces with no discernible defects or phase separation, as well as minimal morphological and compositional changes in the optimized fibers after hydrolysis. Collectively, these results demonstrate that the exceptional hydrolytic durability of PLA/PBS blend fibers arises from the synergistic interplay of selective (203) crystalline coherence, preserved molecular orientation, and chemical end-group stabilization.

采用芳香族磺酸盐衍生物（成核剂N）和碳二亚胺（抗水解剂Anti-H）对聚乳酸(PLA)/聚丁二酸丁二烯（PBS）共混纤维的水解稳定性进行了系统研究。纯PLA/PBS共混纤维（3wt % PBS）在水解后仅保留了其初始拉伸强度的~ 53.9%，而含有成核剂(N)和抗水解剂（Anti-H）的纤维则保留了其初始强度的97.2%。DSC和2D-WAXD分析表明，N选择性地促进了PLA（203）晶体反射的发展和保留，同时增强了PLA(200)/(110)平面的结晶度和分子取向。1D-WAXD表明PLA（203）与PLA(200)/(110)反射强度比与水解保留呈玻尔兹曼型s型关系，临界阈值x0≈0.227。随时间变化的FTIR和XPS分析表明，Anti-H有效地覆盖了末端-COOH基团，抑制了自催化链断裂，并提供了互补的化学稳定性。水解使-COOH和-CO官能团减少，h键-OH增加。相关分析表明-CO的变化对拉伸保持力的影响最大。扫描电镜观察显示，纤维表面光滑，没有明显的缺陷或相分离，优化后的纤维在水解后的形态和成分变化很小。总的来说，这些结果表明PLA/PBS共混纤维的特殊水解耐久性来自于选择性（203）晶体一致性、保留的分子取向和化学端基稳定性的协同相互作用。

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引用次数: 0

Single molecule coupling of light and thermal for programmable energy storage 用于可编程储能的光与热单分子耦合

IF 4.5 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2026-03-06 Epub Date: 2026-01-31 DOI: 10.1016/j.polymer.2026.129684

Yu Fang , Qi Shi , Jinping Qu , Xiang Lu

Efficiently integrating solar and ambient thermal energy within a single molecular system remains a significant challenge. Here we systematically construct a family of azobenzene-based molecules in which photoisomerizable cores are covalently coupled with thermally active alkyl and alkenyl segments. Unlike previous studies focusing on isolated examples, our approach establishes a homologous molecular series that enables direct correlation between structural parameters and dual-mode energy storage behavior. Upon ultraviolet irradiation, the trans-cis isomerization induces lattice disorder and photo‐liquefaction, allowing simultaneous capture of photon energy and latent heat. The reverse process triggered by light or heat releases both chemical and phase-change enthalpies in a single synergistic step. The system exhibits a gravimetric energy density exceeding 300 J g⁻¹, demonstrating a competitive performance among reported materials. Combined density functional theory and calorimetric analyses quantitatively link the isomerization energetics with crystal packing variations, establishing a predictive relationship between molecular design and thermophysical performance. This systematic strategy provides a data-driven framework for designing programmable photothermal materials and paves the way for high-throughput molecular energy computation.

在单个分子系统中有效地整合太阳能和环境热能仍然是一个重大挑战。在这里，我们系统地构建了一个基于偶氮苯的分子家族，其中光异构核心与热活性烷基和烯基片段共价偶联。与以往的研究不同，我们的方法建立了一个同源分子系列，使结构参数和双模储能行为之间的直接关联成为可能。在紫外线照射下，反式顺式异构化引起晶格紊乱和光液化，允许同时捕获光子能量和潜热。由光或热触发的反向过程在一个协同步骤中同时释放化学焓和相变焓。该系统的重量能量密度超过300 J g−1，在已有的材料中具有竞争力。结合密度泛函理论和量热分析定量地将异构化能量与晶体堆积变化联系起来，建立了分子设计与热物理性能之间的预测关系。该系统策略为设计可编程光热材料提供了数据驱动的框架，并为高通量分子能量计算铺平了道路。

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引用次数: 0

Tuning segmental dynamics of PVDF in blends with linear precursors and single-chain nanoparticles: Insights from broadband dielectric spectroscopy PVDF与线性前驱体和单链纳米颗粒共混物的调谐段动力学：来自宽带介电光谱的见解

IF 4.5 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2026-03-06 Epub Date: 2026-01-31 DOI: 10.1016/j.polymer.2026.129682

Manuel Gomez-Menendez , Vasiliki Maria Stavropoulou , Isabel Asenjo-Sanz , José A. Pomposo , Ester Verde-Sesto , Silvia Arrese-Igor , Jon Maiz

The dynamic behavior of poly(vinylidene fluoride) (PVDF) in blends with either a PMMA-based linear precursor copolymer or its single-chain nanoparticle (SCNP) counterpart was investigated using broadband dielectric spectroscopy (BDS) over 125–500 K. Structural and thermal characterization revealed that both the precursor and SCNP components remain glassy under these conditions, while PVDF exhibits active segmental mobility near its α-relaxation. In PVDF-rich blends, SCNPs induce phase separation, preserving the intrinsic α- and β-relaxations of PVDF, whereas the linear precursor promotes partial mixing, attenuating the α-relaxation and lowering the apparent glass transition temperature (T_g) due to the surrounding glassy component. At intermediate and low PVDF contents, both blend types exhibit more complex relaxation spectra, reflecting enhanced interfacial interactions and confinement effects. Analysis of the characteristic relaxation times shows that the activation energy (E_a) of the secondary relaxation increases with the fraction of precursor or SCNPs, indicating hindered local motions due to interfacial constraints or nanoconfinement. Overall, the precursor and SCNP components modulate PVDF dynamics via distinct mechanisms: partial miscibility and dynamic coupling for the precursor, and nanoscale confinement with phase separation for SCNPs, providing strategies to tune segmental dynamics in hybrid glassy polymer systems.

采用宽带介电光谱（BDS）在125-500 K范围内研究了聚偏氟乙烯（PVDF）与pmma线性前驱体共聚物或其单链纳米颗粒（SCNP）共混物中的动力学行为。结构和热表征表明，前驱体和SCNP组分在这些条件下都保持玻璃态，而PVDF在其α-弛豫附近表现出活跃的节段迁移。在富含PVDF的共混物中，SCNPs诱导相分离，保留了PVDF的α-和β-弛豫，而线性前驱体促进了部分混合，由于周围的玻璃化成分，减弱了α-弛豫，降低了表观玻璃化转变温度。在中、低PVDF含量下，两种共混物表现出更复杂的弛豫谱，反映了界面相互作用和约束效应的增强。特征弛豫时间分析表明，二次弛豫的活化能（Ea）随着前驱体或SCNPs含量的增加而增加，表明由于界面约束或纳米限制而阻碍了局部运动。总的来说，前驱体和SCNP组分通过不同的机制调节PVDF动力学：前驱体的部分混相和动态耦合，以及SCNP的纳米级相分离限制，为调整杂化玻璃聚合物体系中的段动力学提供了策略。

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引用次数: 0