Polymer Degradation and Stability最新文献_第2页

Unveiling the role of localized secondary crystallization in poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) aging and its effective reversal via annealing 揭示了局部二次结晶在聚（3-羟基丁酸-co-3-羟基己酸）时效过程中的作用及其退火过程的有效逆转

IF 7.4 2区化学 Q1 POLYMER SCIENCE

Polymer Degradation and Stability

Pub Date : 2026-01-20 DOI: 10.1016/j.polymdegradstab.2026.111950

Pengwu Xu , Yongchun Mo , Jiale Liu , Weijun Yang , Yunsheng Xu , Deyu Niu , Piming Ma

Polyhydroxyalkanoates (PHAs) represent promising biodegradable and biocompatible materials for packaging and biomedical applications, yet their practical implementation is hindered by mechanical deterioration during storage. This study elucidates the aging mechanism of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) through systematic investigation of its room-temperature structural evolution. We demonstrate that localized secondary crystallization in amorphous regions, while minimally increasing overall crystallinity (<1%), fundamentally limits chain mobility by elevating the rigid amorphous fraction and glass transition temperature (T_g), ultimately inducing embrittlement. Crucially, we provide the first direct evidence of this structural ordering through decreased small-angle X-ray scattering invariant (Q) values, confirming low-density secondary crystal formation. Remarkably, annealing above T_g effectively reverses aging by eliminating secondary crystals while promoting lamellar thickening and amorphous region homogenization. The consequent narrowing of long-period distribution facilitates uniform stress transfer, enabling simultaneous recovery of strength and toughness: elongation at break recovers from 2.9% to 10.3% alongside tensile strength improvement from 21.9 MPa to 37.8 MPa. These findings establish both a fundamental understanding of PHBH aging and a practical recovery strategy, advancing its potential for sustainable applications.

聚羟基烷酸酯（PHAs）代表了包装和生物医学应用中有前途的可生物降解和生物相容性材料，但它们的实际实施受到储存过程中机械变质的阻碍。本研究通过对聚（3-羟基丁酸酯-co-3-羟基己酸酯）（PHBH）室温结构演变的系统研究，阐明了其老化机理。我们证明，在非晶态区域的局部二次结晶，虽然最低限度地增加了整体结晶度（<1%），但通过提高刚性非晶态分数和玻璃化转变温度（Tg），从根本上限制了链迁移率，最终导致脆化。至关重要的是，我们通过减小的小角度x射线散射不变量(Q)值提供了这种结构有序的第一个直接证据，证实了低密度二次晶体的形成。值得注意的是，Tg以上的退火通过消除二次晶体而有效地逆转了时效，同时促进了片层增厚和非晶区均匀化。由此产生的长周期分布的收窄有利于均匀的应力传递，使强度和韧性同时恢复：断裂伸长率从2.9%恢复到10.3%，抗拉强度从21.9 MPa提高到37.8 MPa。这些发现建立了对PHBH老化的基本理解和实际的回收策略，提高了其可持续应用的潜力。

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引用次数: 0

From simulation to distribution: A novel approach to depolymerization kinetics using PHB hydrolysis as a case study 从模拟到分布：以PHB水解为例研究解聚动力学的新方法

IF 7.4 2区化学 Q1 POLYMER SCIENCE

Polymer Degradation and Stability

Pub Date : 2026-01-17 DOI: 10.1016/j.polymdegradstab.2026.111949

Norbert Hohenauer , Dominik Wielend , Katharina Kelderer , Jan-Michael Holzinger , Gunnar Spiegel , Clemens Schwarzinger , Christian Paulik

The Flory–Schulz distribution has long been used to describe the probability mass function of polymerization processes, enabling the calculation of polymerization kinetics. However, an equivalent distribution function for depolymerization processes remains elusive. In this study, we present a novel simulation-assisted kinetics model to investigate the depolymerization dynamics of polyhydroxybutyrate (PHB).

Our simulation replicates the random scission of a linear polymer chain and is calibrated against experimental data, yielding a conversion parameter that quantifies the extent of bond cleavage within the polymer. This conversion was then incorporated into the established pseudo second-order reaction kinetics for PHB to describe the temporal evolution of the depolymerization process.

A key assumption in the model is that oligomers with six or fewer repeating units are water-soluble and constitute the measurable depolymerization yield. The simulation provides the proportion of these small oligomers, which were fitted as a function of conversion. This relationship was integrated into the kinetics model, resulting in a predictive expression for the water-soluble yield over time.

To further simplify the application of the simulation results, we derived an analytical distribution function that approximates the fragment length distribution resulting from random chain scission. This distribution reproduces the simulation outcomes with high accuracy and enables easier application in analytical and modeling contexts. Together, the kinetics model and distribution function offer a comprehensive and practical framework for understanding and predicting polymer degradation behavior.

Flory-Schulz分布长期以来被用来描述聚合过程的概率质量函数，使聚合动力学的计算成为可能。然而，解聚过程的等效分布函数仍然难以捉摸。在这项研究中，我们提出了一个新的模拟辅助动力学模型来研究聚羟基丁酸酯（PHB）的解聚动力学。我们的模拟模拟了线性聚合物链的随机断裂，并根据实验数据进行了校准，得到了一个转化参数，该参数可以量化聚合物中键断裂的程度。然后将这种转化纳入已建立的PHB伪二级反应动力学中，以描述解聚过程的时间演化。模型中的一个关键假设是具有六个或更少重复单元的低聚物是水溶性的，并且构成可测量的解聚收率。模拟得到了这些小聚物的比例，并将其拟合为转化率的函数。这种关系被整合到动力学模型中，从而得到了随时间变化的水溶性产率的预测表达式。为了进一步简化模拟结果的应用，我们推导了一个近似于随机链断裂产生的片段长度分布的解析分布函数。这种分布以高精度再现仿真结果，并使分析和建模上下文中的应用更容易。总之，动力学模型和分布函数为理解和预测聚合物降解行为提供了一个全面和实用的框架。

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引用次数: 0

Tuning sequence length to regulate both toughness and biodegradation behavior of poly (butylene succinate-co-butylene adipate) 调整序列长度调节聚丁二酸-己二酸共丁二烯的韧性和生物降解行为

IF 7.4 2区化学 Q1 POLYMER SCIENCE

Polymer Degradation and Stability

Pub Date : 2026-01-16 DOI: 10.1016/j.polymdegradstab.2026.111948

Haoran Sun , Shufeng Li , Junyu Li , Yuchuan Tian , Yi Liu , Liuchun Zheng

The extensive use of conventional plastics has resulted in severe environmental pollution, driving increasing interest in biodegradable polyesters that combine excellent performance with complete degradability. Poly (butylene succinate-co-butylene adipate) (PBSA), derived from poly (butylene succinate) (PBS) by incorporating flexible butylene adipate (BA) units, exhibits broad potential in composting, packaging, and agricultural films. In this study, a series of PBSA polyester materials with systematically varied BA unit sequence lengths were prepared by fine-tuning the composition of adipic acid (AA) and succinic acid (SA), aiming to investigate the effect of BA sequence length on the properties of PBSA. The results indicate that as the BA sequence length decreases, the crystal growth orientation of PBSA shifts from (020), (021), and other planes to (111), accompanied by increased interlamellar spacing and reduced crystallinity, these changes significantly accelerate the enzymatic degradation rate. Meanwhile, the shortened BA sequence promotes spherulite growth, which restricts the mobility of molecular chains and consequently leads to decreases in elongation at break and impact strength. Specific data show that after the shortening of the BA sequence, the elongation at break of PBSA decreases from 810% to 350%, the impact strength drops from 307.2 J/m to 211.9 J/m, and the degradation mass loss rate increases from 71.2% to 99.5%. This study confirms that regulating the BA sequence length enables the synergistic control of both mechanical properties and degradation performance of PBSA polyester materials.

传统塑料的广泛使用造成了严重的环境污染，促使人们对具有优异性能和完全可降解性的可生物降解聚酯越来越感兴趣。聚丁二酸-己二酸共丁二酸酯（PBSA），由聚丁二酸酯（PBS）通过结合柔性己二酸丁二烯（BA）单元衍生而来，在堆肥、包装和农用薄膜方面表现出广泛的潜力。本研究通过对己二酸（AA）和琥珀酸（SA）的组成进行微调，制备了一系列BA单元序列长度系统变化的PBSA聚酯材料，旨在研究BA序列长度对PBSA性能的影响。结果表明，随着BA序列长度的减小，PBSA的晶体生长方向由（020）、（021）等平面向（111）平面转变，层间间距增大，结晶度降低，酶解速率明显加快。同时，缩短的BA序列促进了球晶的生长，限制了分子链的迁移，从而导致断裂伸长率和冲击强度下降。具体数据表明，缩短BA序列后，PBSA的断裂伸长率从810%下降到350%，冲击强度从307.2 J/m下降到211.9 J/m，降解质量损失率从71.2%上升到99.5%。本研究证实，调节BA序列长度可以协同控制PBSA聚酯材料的力学性能和降解性能。

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引用次数: 0

Novel biosurfactant assisted biodegradation of polystyrene by Actinomycetes and its chemical understanding 新型生物表面活性剂辅助放线菌生物降解聚苯乙烯及其化学性质的研究

IF 7.4 2区化学 Q1 POLYMER SCIENCE

Polymer Degradation and Stability

Pub Date : 2026-01-16 DOI: 10.1016/j.polymdegradstab.2026.111946

Amrapali Sakpal , Nazrul Haq , Santanu Dasgupta , Fars Alanazi , Ibrahim A. Alsarra , Mahboob Alam , Syed G. Dastager

The current study highlights the effective biodegradation of polystyrene by two actinobacterial strains, Glutamicibacter sp. K-1 and Rhodococcus sp. BG-30. FT-IR, Raman spectroscopy, and GPC data showed the degradation pattern of polystyrene. Additionally, GC-MS analysis showed that strain K-1 produced a variety of degradation by-products, including alkanes, 2,4-Di-ter-butyl phenol, 2-propenoic acid, tridecyl ester, and dibutyl phthalate, while strain BG-30 produced a greater amount of alkenes, phthalic acid, and isobutyl octyl esters. GPC detected a drop in polystyrene's average molecular weight (Mn), which suggests chain scission of the polymer. Changes in polystyrene's roughness and other morphological properties were shown by AFM and FE-SEM. The effects of a conventional rhamnolipid and a novel thermostable biosurfactant fatty alkene (0.1 % each) on the breakdown of polystyrene were examined. Strain K-1 and BG-30 resulted in increasing the degradation of polystyrene to 12 % (w/w) and 16 % (w/w), respectively in the presence of fatty alkene biosurfactant, there was 10 % (w/w) and 8 % (w/w), degradation in presence of rhamnolipid. To the best of our knowledge, degradation of polystyrene by Glutamicibacter sp. has been reported as a newly identified strain and use of a novel biosurfactant together revealed their potential in biodegradation of plastic to mitigate the plastic pollution using microbial resources.

目前的研究重点是两种放线菌菌株谷氨酰胺杆菌sp. K-1和红球菌sp. BG-30对聚苯乙烯的有效生物降解。FT-IR，拉曼光谱和GPC数据显示了聚苯乙烯的降解模式。此外，GC-MS分析表明，菌株K-1产生了多种降解副产物，包括烷烃、2,4-二叔丁基苯酚、2-丙烯酸、三烷基酯和邻苯二甲酸二丁酯，而菌株BG-30产生了更多的烯烃、邻苯二甲酸和异丁基辛酯。GPC检测到聚苯乙烯的平均分子量（Mn）下降，这表明聚合物发生了链断裂。AFM和FE-SEM分析了聚苯乙烯的粗糙度和其他形态性能的变化。研究了传统鼠李糖脂和新型耐热生物表面活性剂脂肪烯烃（各0.1%）对聚苯乙烯裂解的影响。菌株K-1和BG-30在脂肪烯烃生物表面活性剂存在下对聚苯乙烯的降解率分别提高到12% （w/w）和16% (w/w)，在鼠李糖脂存在下的降解率分别提高到10% （w/w）和8% （w/w）。据我们所知，谷氨酰胺杆菌是一种新发现的降解聚苯乙烯的菌株，而新型生物表面活性剂的使用显示了它们在塑料生物降解方面的潜力，可以利用微生物资源减轻塑料污染。

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引用次数: 0

Improving flame retardancy, mechanical and water resistance properties of polypropylene using zinc oleate-modified intumescent flame retardant and coated red phosphorus 用油酸锌改性膨胀阻燃剂和包覆红磷改善聚丙烯的阻燃性能、力学性能和耐水性

IF 7.4 2区化学 Q1 POLYMER SCIENCE

Polymer Degradation and Stability

Pub Date : 2026-01-15 DOI: 10.1016/j.polymdegradstab.2026.111947

Ziyi Zhang , Yangming Zou , Jun Sun , Hongfei Li , Qing Zhang , Xiaoyu Gu , Sheng Zhang

To address the issue of excessive addition amount when using the expansive intumescent flame retardant (IFR, PAPP:MPP = 7:3) alone, a combination of high flame retardant efficiency and low toxicity coated red phosphorus ((w)RP) and IFR was added to polypropylene (PP) to improve the flame retardant performance of the PP composite. When the total addition amount of flame retardant decreases to 13 wt.%, it still could reach the UL-94 V-0 rating, with a limit oxygen index (LOI) value of 27.2%. Subsequently, in order to synergistically enhance its flame retardant performance, mechanical properties, and water resistance, the IFR needed to be modified. Zinc oleate (ZnOA) has good compatibility with PP and hydrophobicity, so it was selected to modify IFR to synthesis ZnOPM. Compared to PP/10%IFR/3%(w)RP, the PP/10%ZnOPM/3%(w)RP composite showed increased LOI to 28.8% while maintaining UL-94 V-0 rating, with peak heat release rate (pHRR) and total smoke production (TSP) reduced by 23.1% and 71.5% respectively. Additionally, compared with PP/10%IFR/3%(w)RP, the tensile strength and elongation at break of PP/10%ZnOPM/3%(w)RP increased by 25.1% and 98.1%. After water immersion tests, water absorption and flame retardant leaching rate of PP/10%ZnOPM/3%(w)RP decreased to 0.6% and 0.38%, with the composite maintaining excellent flame retardancy and mechanical properties. This study proposes a highly promising strategy for manufacturing PP composites with excellent flame retardant, smoke suppression, water resistance, and mechanical properties.

为解决膨胀型膨胀型阻燃剂（IFR, ppp:MPP = 7:3）单独使用时添加量过大的问题，在聚丙烯（PP）中添加高难燃低毒包覆红磷（(w)RP）和IFR的组合，以提高PP复合材料的阻燃性能。当阻燃剂的总添加量减少到13 wt.%时，仍能达到UL-94的V-0额定值，极限氧指数（LOI）为27.2%。随后，为了协同提高其阻燃性能、机械性能和耐水性，需要对IFR进行改性。油酸锌（ZnOA）与PP具有良好的相容性和疏水性，因此选择它对IFR进行改性以合成ZnOPM。与PP/10%IFR/3%(w)RP相比，PP/10%ZnOPM/3%(w)RP复合材料在保持UL-94 V-0额定值的同时，LOI提高至28.8%，峰值放热率（pHRR）和总产烟率（TSP）分别降低23.1%和71.5%。与PP/10%IFR/3%(w)RP相比，PP/10%ZnOPM/3%(w)RP的拉伸强度和断裂伸长率分别提高了25.1%和98.1%。经浸水试验，PP/10%ZnOPM/3%(w)RP的吸水率和阻燃浸出率分别降至0.6%和0.38%，复合材料保持了优异的阻燃性能和力学性能。该研究为制造具有优异阻燃、抑烟、耐水和机械性能的PP复合材料提供了一种非常有前途的策略。

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引用次数: 0

Synthesis and degradation mechanisms of Schiff-base-containing phthalonitrile resins: Thermal stability and bond reconfiguration 含席夫碱邻苯二腈树脂的合成及降解机理：热稳定性和键重构型

IF 7.4 2区化学 Q1 POLYMER SCIENCE

Polymer Degradation and Stability

Pub Date : 2026-01-15 DOI: 10.1016/j.polymdegradstab.2026.111945

Xiaolu Sun , Shilin Wang , Siyuan Dong , Xi Chen , Xinbo Dong , Yang Wang , Xigao Jian , Cheng Liu

With the rapid development of the aerospace field, higher requirements have been put forward for the heat resistance of thermosetting resins. In this study, an asymmetrical phthalonitrile monomer containing Schiff base moiety (SchB-PN) was synthesized by a two-step method with N-4′-hydroxybenzylidene-4-hydroxyaniline (N-hy) and 4-nitro-o-phthalonitrile. The structure and properties of SchB-PN were characterized by ¹H NMR, ¹³C NMR, ¹H–¹H gCOSY, HRMS, FTIR, XRD, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and rheology. SchB-PN had a relatively low viscosity of 0.179 Pa·s when molten, and due to the presence of imine and cyano groups, SchB-PN resin exhibited self-curing characteristics. Furthermore, SchB-PN resins were cured with different curing agents and curing processes. It was found that SchB-PN-APn-400 resin cured by SchB-PN and p-aminobenzonitrile (APn) at 400 °C demonstrated excellent thermal stability and thermal oxidative stability, with the temperature of 5 % weight loss (T_{5 %}) of 530 °C in nitrogen and 534 °C in air, and the residual carbon rate was 74.9 % at 800 °C in nitrogen atmosphere. The curing mechanism of SchB-PN-APn resin and the cooperative curing mechanism of imine bonds and cyano groups were studied and clarified through FTIR, in-situ infrared technology, SEM and EDS. In addition, the thermal stability and pyrolysis mechanism of SchB-PN were systematically investigated by TGA and TG-FTIR techniques, as well as the compensatory effect of the Schiff base bond breaking and reconnection during the degradation process. The relevant data and analysis results highlight the potential application prospects of SchB-PN-APn resin in aerospace and high-performance engineering fields.

随着航空航天领域的飞速发展，对热固性树脂的耐热性提出了更高的要求。本研究以N-4′-羟基苄基-4-羟基苯胺（N-hy）和4-硝基-邻苯二腈为原料，采用两步法合成了含席夫碱部分的不对称邻苯二腈单体（SchB-PN）。采用¹H NMR、13C NMR、1h gCOSY、HRMS、FTIR、XRD、差示扫描量热法（DSC）、热重分析（TGA）和流变学表征了SchB-PN的结构和性能。熔融时，SchB-PN树脂的粘度较低，为0.179 Pa·s，由于亚胺和氰基的存在，SchB-PN树脂具有自固化特性。此外，采用不同的固化剂和固化工艺对SchB-PN树脂进行了固化。结果表明，SchB-PN-APn-400树脂经SchB-PN和对氨基苯腈（APn）在400℃固化后，表现出优异的热稳定性和热氧化稳定性，在530℃的氮气和534℃的空气中，其失重率（T5 %）为5%，在800℃的氮气气氛中，残碳率为74.9%。通过FTIR、原位红外技术、SEM和EDS等研究并阐明了SchB-PN-APn树脂的固化机理以及亚胺键与氰基的协同固化机理。此外，通过TGA和TG-FTIR技术系统地研究了SchB-PN的热稳定性和热解机理，以及降解过程中席夫碱键断裂和重连的补偿作用。相关数据和分析结果突出了SchB-PN-APn树脂在航空航天和高性能工程领域的潜在应用前景。

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引用次数: 0

Biomimetic soil-root-mineral system toward VER composites with enhanced mechanical property, good recyclability and excellent flame retardancy 仿生土壤-根-矿物体系研究VER复合材料力学性能增强、可回收性好、阻燃性优异

IF 7.4 2区化学 Q1 POLYMER SCIENCE

Polymer Degradation and Stability

Pub Date : 2026-01-15 DOI: 10.1016/j.polymdegradstab.2026.111943

Ying-Ming Li , Hang-Ping Fang , Shuang-Lin Hu , Yao Deng , De-Yi Wang

The inherent flammability, poor mechanical property and non-recyclability of vinyl resins (VER) has hindered their widely use in aerospace and construction applications. In this work, inspired by the soil-root-mineral synergy in natural ecosystems, a novel P-N flame retardant (AT) was covalently immobilized within the polymer matrix, mimicking root anchoring in soil. Concurrently, functionalized glass fibers (FGF) were incorporated, analogous to mineral particles, to synergistically enhance the flame retardancy and mechanical reinforcement for VER. When incorporating 14 wt% AT and 1 wt% FGF, the composite achieved a UL-94 V-0 rating with a limiting oxygen index (LOI) of 31.3%. Cone calorimetry test (CCT) revealed that the VERAT/FGF₁ composite exhibited significant reductions in heat release rate (HRR), total heat release (THR), and smoke production rate (SPR) of 54.4%, 39.3%, and 20.1%, respectively, compared to pure VER. Comprehensive analyses demonstrated that the flame-retardant mechanism involved synergistic effects in both condensed and gas phases. Simultaneously, the VERAT/FGF₁ composite demonstrated 41.9% and 10.7% enhancements in tensile strength and impact resistance, respectively, compared to neat VER. Chemical degradation of VERAT/FGF₁ by solvent method for efficient recycling of glass fibers, providing a new strategy for reuse of vinyl polyester composites.

乙烯基树脂（VER）固有的易燃性、较差的力学性能和不可回收性阻碍了其在航空航天和建筑领域的广泛应用。在这项工作中，受自然生态系统中土壤-根-矿物协同作用的启发，一种新型的P-N阻燃剂（AT）被共价固定在聚合物基质中，模仿土壤中的根锚定。同时，加入功能化玻璃纤维（FGF），类似于矿物颗粒，以协同增强VER的阻燃性和机械增强。当掺入14 wt%的AT和1 wt%的FGF时，该复合材料达到了UL-94 V-0等级，极限氧指数（LOI）为31.3%。锥量热测试（CCT）显示，与纯VER相比，VERAT/FGF1复合材料的放热率（HRR）、总放热率（THR）和产烟率（SPR）分别显著降低54.4%、39.3%和20.1%。综合分析表明，其阻燃机理涉及凝聚态和气相的协同作用。同时，与纯VER相比，VERAT/FGF1复合材料的拉伸强度和抗冲击性分别提高了41.9%和10.7%。溶剂法化学降解VERAT/FGF1可有效回收玻璃纤维，为乙烯基聚酯复合材料的再利用提供了新的策略。

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引用次数: 0

Ionic liquid functionalized h-BN enhanced polyurethane power battery sealants 离子液体功能化h-BN增强聚氨酯动力电池密封胶

IF 7.4 2区化学 Q1 POLYMER SCIENCE

Polymer Degradation and Stability

Pub Date : 2026-01-15 DOI: 10.1016/j.polymdegradstab.2026.111944

Xiongzhuang Gao, Xingyuan Ma, Xinyuan Xue, Lu Lin

With the continuous development of battery technology for new energy vehicles (NEVs), the comprehensive performance requirements for power battery sealants are growing increasingly demanding. This study proposes an innovative strategy for preparing high-performance polyurethane power battery sealants (PUSs) by introducing ionic liquid functionalized boron nitride nanosheets (IL-fhBNNS) as a multifunctional filler. [BMIM]PF₆ was used to exfoliate and functionalize h-BN via heating and stirring method, successfully yielding IL-fhBNNS with an average lateral size of 1.59 μm and a thickness of 3.77 nm. Based on polyurethane prepolymer (PUP) and IL-fhBNNS, a series of PUSs samples were successfully synthesized via the prepolymer method combined with casting molding method. The effects of the addition of IL-fhBNNS on the thermal conductivity (TC), flame retardancy, mechanical properties, adhesion and solvent resistance of sealants were investigated. Based on the comprehensive experimental results, the PUS-4 demonstrated optimal comprehensive properties. Thanks to the dense three-dimensional heat conduction network formed by IL-fhBNNS in the PU matrix, the TC of PUS-4 reached 2.701 W m^-1 K^-1, representing an increase of 963.39 % over pure PU. Meanwhile, PUS-4 exhibited excellent thermal stability and flame retardancy, significantly reducing the PHRR (265.69 kW/m²) and THR (59.09 MJ/m²) by 44.19 % and 35.70 %, respectively, and reaching the flame retardant rating of V-0 compared with pure PU. Besides, PUS-4 exhibited excellent mechanical properties, with stress and strain reaching 43.98 MPa and 550.16 %, respectively. PUS-4 also showed satisfactory adhesive performance solvent resistance. The lap shear force of PUS-4 on steel substrates reached 3382.56 N. Therefore, PUSs demonstrate great application potential in addressing the challenges of thermal management and sealing in power batteries.

随着新能源汽车电池技术的不断发展，对动力电池密封胶的综合性能要求越来越高。本研究通过引入离子液体功能化氮化硼纳米片（IL-fhBNNS）作为多功能填料，提出了制备高性能聚氨酯动力电池密封胶（PUSs）的创新策略。[BMIM]PF6通过加热搅拌的方法对h-BN进行剥离和功能化，成功制备出平均横向尺寸为1.59 μm、厚度为3.77 nm的IL-fhBNNS。以聚氨酯预聚体（PUP）和IL-fhBNNS为基础，通过预聚体法和浇铸成型法相结合，成功合成了一系列PUSs样品。研究了IL-fhBNNS的加入对密封胶导热性、阻燃性、力学性能、附着力和耐溶剂性的影响。综合实验结果表明，pu -4具有最佳的综合性能。由于IL-fhBNNS在PU基体中形成致密的三维热传导网络，PU -4的TC达到2.701 W m-1 K-1，比纯PU提高了963.39%。同时，PU -4表现出优异的热稳定性和阻燃性，与纯PU相比，其PHRR （265.69 kW/m2）和THR （59.09 MJ/m2）分别显著降低44.19%和35.70%，阻燃等级达到V-0。此外，pu -4具有优异的力学性能，应力和应变分别达到43.98 MPa和550.16%。pus4也表现出良好的粘接性能。PUSs -4在钢基板上的剪切力达到3382.56 N.因此，PUSs在解决动力电池的热管理和密封挑战方面显示出巨大的应用潜力。

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引用次数: 0

Macromolecular mobility changes in virgin and thermally aged epoxies 原生和热老化环氧树脂中大分子迁移率的变化

IF 7.4 2区化学 Q1 POLYMER SCIENCE

Polymer Degradation and Stability

Pub Date : 2026-01-14 DOI: 10.1016/j.polymdegradstab.2026.111938

Emmanuel Richaud , Takato Ishida , Nicolas Delpouve , Hideaki Hagihara

Epoxy diamine systems were thermally oxidized at 110 °C under air. The impact of ageing on the macromolecular relaxation dynamics was monitored using DMA in multi-frequency multi-temperatures mode, whereas structural changes were sought from sol-gel measurements and Positron Annihilation Lifetime Spectroscopy (PALS) measurements. The analyses lead to the conclusion that chain scissions first occur, but are compensated by crosslinking at long ageing times. Thus, the structural heterogeneity increases, as evidenced from the free volume hole sizes distribution. To estimate the changes of relaxation parameters with ageing, the experimental data were exploited using Williams–Landel–Ferry (WLF) and Vogel–Fulcher–Tammann–Hesse (VTFH) equations, showing respectively that C₂^g increases meanwhile the fragility index (m) decreases. These variations are monotonous despite the dual degradation mechanism. It is assumed that the relaxation dynamics are essentially influenced by the cooperativity drop, resulting from internal crosslinks and antiplasticization.

环氧二胺体系在110℃下空气热氧化。老化对大分子弛豫动力学的影响采用多频率多温度模式的DMA监测，而结构变化则通过溶胶-凝胶测量和正电子湮灭寿命光谱（PALS）测量来寻找。分析得出的结论是，链断裂首先发生，但在长时间老化时被交联补偿。因此，结构的非均质性增加，从自由体积孔尺寸分布可以看出。利用Williams-Landel-Ferry （WLF）和Vogel-Fulcher-Tammann-Hesse （VTFH）方程分析了松驰参数随老化的变化，结果表明，C2g增大，脆性指数(m)减小。尽管存在双重降解机制，但这些变化是单调的。假设弛豫动力学本质上受内部交联和抗塑化引起的协同性下降的影响。

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引用次数: 0

Interfacially engineered ceramicized sodium alginate aerogels with enhanced thermal insulation and fire safety for suppressing thermal runaway propagation in lithium-ion batteries 界面工程陶瓷化海藻酸钠气凝胶，具有增强的绝热性和防火安全性，可抑制锂离子电池中的热失控传播

IF 7.4 2区化学 Q1 POLYMER SCIENCE

Polymer Degradation and Stability

Pub Date : 2026-01-12 DOI: 10.1016/j.polymdegradstab.2026.111942

Lingxin He , Jiaqing Zhang , Yi Guo , Yubiao Huang , Junling Wang , Changhao Li , Shuping Wang , Minghao Fan , Tao Sun , Rui Liu

Against the backdrop of widespread utilization of lithium-ion batteries (LIBs), safety concerns have become increasingly prominent. Preventing thermal runaway propagation (TRP) is crucial to improving the fire safety of battery systems. However, existing barrier materials show limited effectiveness in suppressing TRP due to weak interfacial compatibility and poor structural integrity under high temperatures. Herein, we design ceramicized sodium alginate (SA) aerogels with interfacially engineered components via freeze-drying and sol-gel methods. The incorporation of hollow glass microspheres (HGM) and ammonium polyphosphate (APP) establishes robust interfacial interactions within the SA network, promoting uniform ceramic phase formation and enhancing structural stability during combustion. The interfacially reinforced aerogel (SA@HGM-APP-2) exhibits remarkable fire safety performance, with the peak heat release rate (PHRR) reduced by 68.3% compared to pure SA. Thermogravimetric-Infrared (TG-IR) analysis reveals significant suppression of toxic gas emissions, with CO and CO₂ reductions of 92.2% and 89.2%, respectively. Meanwhile, the char residue increases from 35.7% for SA to 48.1% for SA@HGM-APP-2, confirming improved thermal stability through interfacial ceramicization.When applied as a barrier material for LIBs, the interfacially engineered aerogels effectively inhibit TRP. Specifically, for 2 and 3 mm SA aerogels, the Δt between the thermal runaway (TR) of two cells are 312 and 619 s, respectively. In sharp contrast, 2 and 3 mm SA@HGM-APP aerogels completely prevent TRP, with the second cell exhibiting maximum temperatures of only 127.6 and 109.0 °C. Microscopic and structural analyses demonstrate that the cathode of the surviving cell undergoes only minor morphological and compositional changes, further validating the interface-induced thermal barrier mechanism. This work provides new insights into interfacial engineering of biomass-derived aerogels for the rational design of high-performance, fire-safe barriers to ensure the thermal safety of LIBs systems.

在锂离子电池广泛应用的背景下，安全性问题日益突出。防止热失控传播（TRP）是提高电池系统防火安全性的关键。然而，现有的势垒材料由于界面相容性弱，高温下结构完整性差，抑制TRP的效果有限。在此，我们通过冷冻干燥和溶胶-凝胶方法设计了具有界面工程成分的海藻酸钠（SA）陶瓷气凝胶。中空玻璃微球（HGM）和聚磷酸铵（APP）的掺入在SA网络中建立了强大的界面相互作用，促进了均匀的陶瓷相形成，增强了燃烧过程中的结构稳定性。界面增强气凝胶（SA@HGM-APP-2）表现出显著的防火性能，峰值放热率（PHRR）比纯SA降低了68.3%。热重红外（TG-IR）分析显示，有毒气体的排放得到显著抑制，CO和CO 2的排放量分别减少了92.2%和89.2%。同时，焦炭残渣由SA的35.7%增加到SA@HGM-APP-2的48.1%，证实了界面陶瓷化提高了热稳定性。当用作lib的屏障材料时，界面工程气凝胶可以有效地抑制TRP。具体而言，对于2和3 mm SA气凝胶，两个细胞的热失控（TR）之间的Δt分别为312和619 s。与之形成鲜明对比的是，2和3 mm SA@HGM-APP气凝胶完全阻止了TRP，第二个电池的最高温度仅为127.6和109.0°C。显微和结构分析表明，存活电池的阴极只发生了微小的形态和成分变化，进一步验证了界面诱导的热障机制。这项工作为生物质气凝胶的界面工程提供了新的见解，为合理设计高性能，防火屏障以确保lib系统的热安全提供了新的思路。

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引用次数: 0