Polymer Degradation and Stability最新文献

Synergistic effect of modified carbon nanotubes and magnesium hydroxide on flame retardancy and smoke suppression of silicone rubber foam 改性碳纳米管与氢氧化镁对硅橡胶泡沫阻燃抑烟的协同作用

IF 7.4 2区化学 Q1 POLYMER SCIENCE

Polymer Degradation and Stability

Pub Date : 2025-12-03 DOI: 10.1016/j.polymdegradstab.2025.111835

Furu Kang , Jingxiao Pan , Lanlan Guo , Jun Deng , Dengke Wang , Zujin Bai , Shuaijing Ren , Chang Su , Chao Pan , Zibo Tian

To enhance the flame retardancy and smoke suppression of silicone rubber foam (SRF), a composite material of hydroxylated carbon nanotubes (CNTs–OH)/ Mg(OH)₂/ SRF was synthesized. The flame retardancy, smoke suppression performance of the SRF composites were evaluated using limiting oxygen index (LOI), horizontal-vertical burning tests (UL-94), cone calorimetry, and smoke density testing. Furthermore, the composition and toxicity of the combustion-generated smoke were investigated through a smoke density chamber coupled with Fourier-transform infrared spectroscopy and animal toxicity experiments. The results indicate that the SRF composites with 1.5 wt% CNTs–OH and 7 wt% Mg(OH)₂ displayed optimal flame retardancy and smoke suppression, as evidenced by an LOI value of 30.5 % and a UL-94 V-0 classification. The peak heat release rate and total heat release are diminished by 35.5 % and 51.9 %, while the maximum smoke density and total smoke production are lowered by 69.6 % and 70.45 %, respectively. SO₂ was identified as the most critical gas causing casualties during the combustion of SRF composites, followed by CO₂ and CO. The SRF composite with 1.5 wt% CNTs–OH and 7 wt% Mg(OH)₂ was assigned a toxicity rating of ZA1. Moreover, studies reveal that the Mg(OH)₂/CNTs–OH/SRF composite achieves flame retardancy via condensed-phase mechanisms, including Mg(OH)₂-catalyzed dehydration of CNTs–OH to form a dense char, char stabilization by MgO, and the dilution of combustibles by H₂O. Synergistic effects establish dual SiO₂/carbon barriers that block heat and oxygen transfer, enhancing fire resistance and smoke suppression.

为了提高硅橡胶泡沫（SRF）的阻燃性和抑烟性，合成了羟基化碳纳米管(CNTs-OH)/ Mg(OH)2/ SRF复合材料。采用极限氧指数（LOI）、水平-垂直燃烧测试（UL-94）、锥量热法和烟雾密度测试对SRF复合材料的阻燃、抑烟性能进行了评价。此外，通过烟密度室结合傅里叶变换红外光谱和动物毒性实验，研究了燃烧产生的烟雾的组成和毒性。结果表明，添加1.5 wt% CNTs-OH和7 wt% Mg(OH)2的SRF复合材料具有最佳的阻燃和抑烟性能，LOI值为30.5%，UL-94 V-0等级。峰值放热率和总放热率分别降低了35.5%和51.9%，最大烟密度和总产烟量分别降低了69.6%和70.45%。SO2被认为是SRF复合材料燃烧过程中造成人员伤亡的最关键气体，其次是CO2和CO。含有1.5 wt% CNTs-OH和7 wt% Mg(OH)2的SRF复合材料的毒性等级为ZA1。此外，研究表明，Mg(OH)2/ CNTs-OH /SRF复合材料通过缩合相机制实现阻燃，包括Mg(OH)2催化CNTs-OH脱水形成致密炭、MgO稳定炭和H2O稀释可燃物。协同效应建立了双SiO2/碳屏障，阻止了热量和氧气的传递，增强了耐火性和抑烟性。

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引用次数: 0

Cold plasma-assisted degradation of melamine-resin microplastics: A multiscale analysis of fragmentation and morphological evolution 冷等离子体辅助降解三聚氰胺树脂微塑料：碎片和形态演变的多尺度分析

IF 7.4 2区化学 Q1 POLYMER SCIENCE

Polymer Degradation and Stability

Pub Date : 2025-12-01 DOI: 10.1016/j.polymdegradstab.2025.111825

K. Bexeitova , U. Zhantikeyev , Y. Yeszhan , A. Baimenov , K. Toshtay , S. Mikhalovsky , M. Illsley , Jechan Lee , S. Azat

Microplastics, particularly melamine-resin polymers, are emerging environmental contaminants with high persistence and potential toxicity. Conventional degradation methods are often inefficient in fully breaking down stable carbon backbones of such polymers. Cold plasma technology has recently attracted attention as a non-thermal advanced oxidation process capable of generating highly reactive species under ambient conditions. This study aims to investigate the degradation behavior of melamine-resin microplastics under cold plasma treatment and to characterize the structural transformations, fragmentation dynamics, and degradation efficiency over time. A custom-built cold plasma reactor operating at 10 kV and 3 A was used to treat aqueous suspensions of melamine resin microparticles (2 µm). The plasma reactor enabled gas-liquid phase interactions, enhancing the generation of oxidative species. The degradation process was assessed at different exposure times (5, 20 and 30 min). Structural and morphological changes were analyzed using Transmission Electron Microscopy (TEM), Dynamic Light Scattering (DLS), zeta potential measurements, turbidity analysis, and gravimetric mass loss.

Cold plasma treatment induced a progressive reduction in particle size from 2004 ± 93 nm to 119 ± 47 nm after 30 min, accompanied by a 43 % weight loss and increased turbidity (from 2.06 NTU to 7.22 NTU), indicating significant fragmentation. TEM images confirmed morphological transformation from smooth spherical particles to irregular, porous, nano-sized fragments (68–119 nm). Oxidative degradation pathways are attributed to interactions with reactive oxygen species such as •OH, O₃, and H₂O₂ generated within the plasma zone. Cold plasma demonstrates high efficiency in degrading melamine-resin microplastics through advanced oxidative mechanisms, leading to significant fragmentation and nanostructural disruption. The findings support the use of cold plasma as a sustainable and effective method for the remediation of microplastic-contaminated water and offer insights into degradation kinetics and mechanisms of polymer breakdown under plasma exposure.

微塑料，特别是三聚氰胺树脂聚合物，是新兴的具有高持久性和潜在毒性的环境污染物。传统的降解方法在完全分解这种聚合物的稳定碳骨架方面往往效率低下。冷等离子体技术作为一种能够在环境条件下产生高活性物质的非热高级氧化工艺，近年来引起了人们的关注。本研究旨在研究三聚氰胺树脂微塑料在冷等离子体处理下的降解行为，并表征其随时间的结构转变、破碎动力学和降解效率。采用特制的冷等离子体反应器，工作电压为10 kV，电流为3 A，处理2µm的三聚氰胺树脂微颗粒水悬浮液。等离子体反应器使气液相相互作用，增强氧化物质的产生。在不同的暴露时间（5、20和30分钟）下评估降解过程。通过透射电子显微镜（TEM）、动态光散射（DLS）、zeta电位测量、浊度分析和重量质量损失分析结构和形态变化。冷等离子体处理导致30分钟后颗粒尺寸从2004±93 nm逐渐减小到119±47 nm，伴随着43%的重量减轻和浊度增加（从2.06 NTU到7.22 NTU），表明明显的碎片化。TEM图像证实了从光滑的球形颗粒到不规则的多孔纳米碎片（68-119 nm）的形态转变。氧化降解途径归因于与等离子区产生的•OH、O₃和H₂O₂等活性氧物质的相互作用。冷等离子体通过先进的氧化机制高效降解三聚氰胺树脂微塑料，导致显著的碎片化和纳米结构破坏。研究结果支持冷等离子体作为一种可持续和有效的修复微塑料污染水的方法，并提供了等离子体暴露下聚合物降解动力学和降解机制的见解。

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引用次数: 0

Stimulus-responsive multifunctional coating with active protection and antibacterial properties 具有活性保护和抗菌性能的刺激反应多功能涂层

IF 7.4 2区化学 Q1 POLYMER SCIENCE

Polymer Degradation and Stability

Pub Date : 2025-11-29 DOI: 10.1016/j.polymdegradstab.2025.111823

Chengbin Guo , Tian Zhang , Zhenyu Chen

To retard the epoxy coating degradation and microbial adhesion in marine environments, a dual-responsive nanocontainer system, PNIPAM@BTA@MPN, was developed for pH/temperature-triggered self-healing when incorporated into an epoxy matrix. This system consists of thermosensitive poly(N-isopropylacrylamide) (PNIPAM) nanoparticles loaded with the corrosion inhibitor benzotriazole (BTA). These PNIPAM@BTA nanoparticles are then encapsulated within a pH-responsive metal-polyphenol network (MPN). Moreover, an alkaline phosphatase (ALP)-responsive bactericidal hydrogel layer was generated through surface polymerization of methacrylate monomers, utilizing phosphate crosslinkers.

After 50 days of immersion under temperature-alternating conditions, the resistance of the composite coating sample at 0.01 Hz (1.01×10⁹ Ω·cm²) was nearly two orders of magnitude higher than that of the pristine epoxy coating. Density functional theory (DFT) and molecular dynamics (MD) simulations revealed enhanced mechanical integrity and barrier properties. Furthermore, EIS, scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM/EDS), and wire beam electrode (WBE) analyses collectively confirmed the active protection mechanism of the scratched composite coating under conditions of lower pH and higher temperature. In addition to its protective qualities, the ALP-responsive gel layer exhibited notable antibacterial activity, demonstrating an antibacterial efficiency exceeding 80 % against both S. aureus and P. aeruginosa.

This self-adaptive coating offers durable corrosion protection and antimicrobial properties, making it suitable for extended use in marine environments.

为了延缓环氧涂层在海洋环境中的降解和微生物粘附，研究人员开发了一种双响应纳米容器系统PNIPAM@BTA@MPN，该系统可在pH/温度触发的情况下与环氧树脂基体结合进行自修复。该系统由热敏型聚n -异丙基丙烯酰胺（PNIPAM）纳米颗粒组成，负载缓蚀剂苯并三唑（BTA）。然后将这些PNIPAM@BTA纳米颗粒封装在ph响应金属-多酚网络（MPN）中。此外，利用磷酸盐交联剂，通过甲基丙烯酸酯单体的表面聚合，生成了碱性磷酸酶（ALP）响应的杀菌水凝胶层。在温度交替条件下浸泡50 d后，复合涂层样品在0.01 Hz （1.01×109 Ω·cm2）下的电阻比原始环氧涂层高出近两个数量级。密度泛函理论（DFT）和分子动力学（MD）模拟显示了增强的机械完整性和屏障性能。此外，EIS、扫描电镜（SEM/EDS）和线束电极（WBE）分析共同证实了复合涂层在低pH和高温条件下的主动保护机制。除了具有保护作用外，alp反应凝胶层还表现出显著的抗菌活性，对金黄色葡萄球菌和铜绿假单胞菌的抗菌效率均超过80%。这种自适应涂层提供持久的防腐和抗菌性能，使其适合在海洋环境中广泛使用。

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引用次数: 0

Formaldehyde‑free phosphamide flame retardant with high atom economy for cotton based on p-π conjugation 基于p-π共轭的高原子经济性棉花无甲醛磷酰胺阻燃剂

IF 7.4 2区化学 Q1 POLYMER SCIENCE

Polymer Degradation and Stability

Pub Date : 2025-11-29 DOI: 10.1016/j.polymdegradstab.2025.111803

Fayu Sun , Jiayang Li , Hui Xu , Tian Li , Hejun Li , Jieyu Wei , Guangming Sun , Shuai He , Guangxian Zhang

A novel green cotton phosphoramide flame retardant (ACPPFR) was synthesized from phosphorus pentoxide and ammonium carbonate. Phosphorus atoms were introduced into the cotton fabric via the generation of H₂N-P(=O)-O-C bonds with cellulose. The p-π conjugated structure formed by the nitrogen atom and P=O groups reduced the polarity of the phosphate bond and improved its stability. SEM and XRD results suggested that ACPPFR molecules entered the interior of cotton fibers. Energy-dispersive spectroscopy (EDS) elemental analysis showed that ACPPFR was applied to the cotton fibers, and FTIR spectroscopy suggested that it was grafted onto the fabrics via P(=O)-O-C covalent bonds. Thermogravimetric (TG), thermogravimetric infrared (TG-IR), and cone calorimetry data suggested that ACPPFR altered the thermal degradation process of cotton fibers, representing a condensed-phase flame retardant mechanism. Physical property tests suggested that ACPPFR made fabrics softer. According to AATCC 61–2013 3A standard, the LOI value of ACPPFR-20 % was 42.5 %, and the vertical burning damage length was 86 mm after 50 LCs. This indicated that ACPPFR-20 % had high durability and efficient flame retardancy. In this study, amidation reaction was carried out by introducing ammonium ions in inorganic ammonium carbonate, which had high atom economy and was a green reaction.

以五氧化二磷和碳酸铵为原料合成了一种新型绿棉磷酰胺阻燃剂（ACPPFR）。磷原子通过与纤维素生成H2N-P(=O)-O-C键进入棉织物。氮原子与p =O基团形成的p-π共轭结构降低了磷酸键的极性，提高了其稳定性。SEM和XRD结果表明，ACPPFR分子进入棉纤维内部。能谱（EDS）元素分析表明，ACPPFR通过P(=O)-O-C共价键接枝到织物上。热重（TG）、热重红外（TG- ir）和锥量热数据表明，ACPPFR改变了棉纤维的热降解过程，表现为凝聚相阻燃机理。物理性能测试表明，ACPPFR使织物更柔软。根据AATCC 61-2013 3A标准，acppfr - 20%的LOI值为42.5%，50 lc后垂直燃烧损伤长度为86 mm。这表明acppfr - 20%具有高耐久性和高效阻燃性。在无机碳酸铵中引入铵离子进行酰胺化反应，具有较高的原子经济性，是一种绿色反应。

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引用次数: 0

Facile and efficient chemical degradation of end-of-life tires into value-added liquid rubber 将废旧轮胎快速、高效地化学降解为增值液体橡胶

IF 7.4 2区化学 Q1 POLYMER SCIENCE

Polymer Degradation and Stability

Pub Date : 2025-11-28 DOI: 10.1016/j.polymdegradstab.2025.111821

Hua Zhang , Yu Sun , Qi Yang , Xiaojian Liu , Lishuang Ma , Xuequan Zhang , Moris S. Eisen , Heng Liu

The ever-growing accumulation of polydiene sulphur vulcanizates, represented mainly by end-of-life tires (ELTs), causes substantial environmental pollutions, underscoring the urgency for effective and sustainable recycling strategies. In this report, a simple yet efficient synergistic system of Cp₂ZrCl₂/LiAlH₄ has been designed for the chemical degradation of polydiene sulphur vulcanizates, including end-of-life tires. By fine-tuning the reaction conditions, low-molecular-weight liquid polydiene rubbers (LPRs) with tunable chain structures and molecular weights are produced as the final products. The key factors influencing the degradation efficiency were systematically evaluated. Importantly, the resultant LPR can be directly reused as processing aids in new rubber compounds without compromising their mechanical performance, thus enabling a quasi-closed-loop recycling pathway. Overall, this study offers a sustainable solution to the growing challenge of managing tire waste.

以报废轮胎为代表的聚二烯硫硫化橡胶的不断积累造成了严重的环境污染，强调了制定有效和可持续的回收战略的紧迫性。在本报告中，设计了一种简单而高效的Cp2ZrCl2/LiAlH4协同体系，用于化学降解聚二烯硫硫化橡胶，包括报废轮胎。通过对反应条件的微调，可制得链结构和分子量可调的低分子量液态聚二烯橡胶（LPRs）。系统评价了影响降解效率的关键因素。重要的是，合成的LPR可以直接用作新橡胶化合物的加工助剂，而不会影响其机械性能，从而实现准闭环回收途径。总的来说，这项研究提供了一个可持续的解决方案，以管理轮胎废物日益增长的挑战。

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引用次数: 0

Adaptive crosslinking of guar gum-polyborate network to impart efficient flame retardancy to cotton fabrics 瓜尔胶-聚硼酸酯网络自适应交联对棉织物的阻燃性能研究

IF 7.4 2区化学 Q1 POLYMER SCIENCE

Polymer Degradation and Stability

Pub Date : 2025-11-28 DOI: 10.1016/j.polymdegradstab.2025.111812

Chao Ling

In pursuit of halogen-free, formaldehyde-free, and phosphorus-free flame retardants, this study synthesized a high-efficiency boron-based flame retardant, sodium polyborate (SPB), via the reaction between boric acid and borax. A novel methodology was developed involving the grafting of guar gum onto cotton fibers using citric acid and sodium hypophosphite as catalysts, followed by SPB loading through leveraging the unique cross-linking ability between guar gum and polyborate. Structural characterization using Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS) confirmed the successful fabrication of guar gum/SPB-treated cotton fabric (COT-GB). Thermogravimetric analysis (TGA) demonstrated that COT-GB with a 5 % weight gain exhibited 35.0 % residual char retention at 800 °C. Vertical flammability tests revealed self-extinguishing behavior with a char length of 5.2 cm and a limiting oxygen index (LOI) of 34.1 %. Cone calorimetry results indicated 81.3 % reduction in peak heat release rate and 47.4 % decrease in total heat release for COT-GB, demonstrating exceptional flame retardancy at ultra-low additive loading. TG-IR and Py-GC–MS analyses revealed that SPB catalyzed the carbonization of the cellulose to generate a compact char barrier, thereby suppressing flammable gas emissions. This work establishes an efficient strategy for engineering high-performance boron-based flame retardants in cotton textiles.

为了追求无卤、无甲醛、无磷的阻燃剂，本研究通过硼酸与硼砂的反应合成了高效硼基阻燃剂聚硼酸钠（SPB）。采用柠檬酸和次磷酸钠作为催化剂，利用瓜尔胶和聚硼酸酯之间独特的交联能力负载SPB，将瓜尔胶接枝到棉纤维上。利用傅里叶红外光谱（FT-IR）、扫描电镜（SEM）和能量色散x射线能谱（EDS）对其进行了结构表征，证实了瓜尔胶/ spb处理棉织物（COT-GB）的成功制备。热重分析（TGA）表明，重量增加5%的COT-GB在800℃时具有35.0%的残炭保留率。垂直可燃性试验表明，该材料具有自熄特性，焦炭长度为5.2 cm，极限氧指数（LOI）为34.1%。锥量热法结果表明，在超低添加剂负荷下，COT-GB的峰值放热率降低了81.3%，总放热率降低了47.4%，表现出优异的阻燃性。TG-IR和Py-GC-MS分析表明，SPB催化纤维素的碳化，产生致密的炭屏障，从而抑制可燃气体的排放。本研究为棉纺织用高性能硼基阻燃剂的研制提供了一种有效的策略。

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引用次数: 0

Chemical degradation and Upcycling of discarded polyester-spandex blended fabrics to high Tg transparent polyester 废弃涤纶-氨纶混纺织物的化学降解及高Tg透明聚酯的升级利用

IF 7.4 2区化学 Q1 POLYMER SCIENCE

Polymer Degradation and Stability

Pub Date : 2025-11-28 DOI: 10.1016/j.polymdegradstab.2025.111819

Haomeng Ma , Hongbin Li , Guangmou Cao , Yang Yu , Xiaolong Wang , Xuedong Lv , Xueshuai Wang , Shufeng Li , Liuchun Zheng

Textiles, as a fast-moving consumer goods (FMCG), are mass produced and used in modern daily life. Polyester-spandex blended fabrics, a major category of pure chemical fiber products, are primarily recycled through the mechanical recycling or chemical degradation, with a notable lack of research on upcycling. We propose a chemical degradation and upcycling pathway based on transesterification principles to prepare high-value transparent poly(ethylene terephthalate)-tricyclodecanedimetthanol (TCDDM) copolymer by discarded polyester-spandex blended fabrics. Employing a selective separation strategy, the spandex component of the polyester-spandex blended fabrics was separated with dimethylacetamide (DMAC) solvent. Then, the separated polyester fabric was chemical degradation with ethylene glycol (EG) solvent to obtain the bis(2-hydroxyethyl) terephthalate (BHET) monomer. The reaction was carried out at 190 ℃ for 3 h by setting up a reflux apparatus. This is milder reaction conditions and simpler setup than methanolysis. Finally, the upcycling of r-PETGs containing TCDDM was carried out via melt polycondensation. The r-PETGs possess higher T_g of 85.6–115.4 ℃, and can be utilized in transparent application scenarios under high temperatures. Our work offers a pathway for degrading and upcycling textile waste by transforming it into high-value transparent materials, supporting chemical degradation and circular economy in the fiber industry.

纺织品作为一种快速消费品（FMCG），在现代日常生活中被大量生产和使用。涤纶-氨纶混纺织物是纯化纤产品的主要门类，主要通过机械回收或化学降解的方式回收，对升级回收的研究明显不足。提出了一种基于酯交换原理的化学降解和升级回收途径，以废弃聚酯-氨纶混纺织物为原料制备高价值透明聚对苯二甲酸乙酯-三环癸二甲基乙醇共聚物。采用选择性分离策略，用二甲基乙酰胺（DMAC）溶剂分离涤纶-氨纶混纺织物中的氨纶成分。然后，用乙二醇（EG）溶剂对分离的涤纶织物进行化学降解，得到对苯二甲酸双（2-羟乙基）酯（BHET）单体。建立回流装置，在190℃下反应3 h。这是一种较温和的反应条件和较简单的装置。最后，采用熔融缩聚法对含TCDDM的r-PETGs进行了升级回收。r-PETGs具有较高的Tg（85.6-115.4℃），可用于高温下的透明应用场合。我们的工作为纺织废料的降解和升级利用提供了一条途径，将其转化为高价值的透明材料，支持纤维工业的化学降解和循环经济。

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引用次数: 0

Design and synthesis of an anhydride-terminated imide oligomer containing phosphorus and Schiff base for high-performance and flame-retarded GF/PA66 composites: Experiment and simulation 高性能阻燃GF/PA66复合材料中含磷希夫碱端酸酐亚胺低聚物的设计与合成：实验与模拟

IF 7.4 2区化学 Q1 POLYMER SCIENCE

Polymer Degradation and Stability

Pub Date : 2025-11-28 DOI: 10.1016/j.polymdegradstab.2025.111814

Lei Li , Jingming Gao , Lutao Zhang , Shumei Liu , Pengwei Duan , Xing Liu , Jianqing Zhao

Glass fiber (GF) is deemed as a double-edged sword, which enhances the mechanical strength of polymers but simultaneously reduces their processability, toughness and flame retardancy. It is still a great challenge to design and manufacture glass fiber reinforced polyamide 66 (GF/PA66) composites with concurrently improved processability, thermal properties, toughness and flame retardancy. Herein, a novel anhydride-terminated imide oligomer (PNFPI) containing phosphorus, fluorine and Schiff base was designed, synthesized and employed as both a compatibilizer and flame retardant for GF/PA66 composites. Thanks to hydrophobic trifluoromethyl and reactive anhydride groups, PNFPI was located at the interface between GF and PA66, and enhanced the interfacial interactions of GF/PA66 via covalent and H bonds, leading to the homogeneous dispersion of GF in composites. At GF loading of 30 wt%, compared to those of GF30/PA, the melt equilibrium torque of the resulting GF reinforced PA66 with 18 wt% PNFPI (PNFPI18) was decreased by 75.0 %, and the limiting oxygen index (LOI) was increased to 31.1 %, along with a UL-94 V-0 rating. Meanwhile, the notch impact strength of PNFPI18 was improved by 2.16 times to 10.91 kJ/m², and heat deflection temperature (HDT) was increased to 240.6 °C from 215.4 °C, compared to those of GF30/PA. Furthermore, molecular dynamics (MD) simulation revealed that PNFPI enhanced intermolecular interactions between GF and PA66, and reduced fractional free volume (FFV) of PNFPI18 by forming a denser interfacial stack. This work provides a new perspective to simultaneously improve the processability, fire safety and mechanical properties of GF/PA66 composites and other polymeric composites.

玻璃纤维是一把双刃剑，它提高了聚合物的机械强度，但同时也降低了聚合物的加工性、韧性和阻燃性。设计和制造同时提高加工性能、热性能、韧性和阻燃性的玻璃纤维增强聚酰胺66 （GF/PA66）复合材料仍然是一个巨大的挑战。本文设计并合成了一种新型的含磷、氟和席夫碱的端酸酐亚胺低聚物（PNFPI），并将其作为GF/PA66复合材料的增容剂和阻燃剂。由于PNFPI的疏水性三氟甲基和活性酸酐基团，PNFPI位于GF和PA66之间的界面，通过共价键和氢键增强GF/PA66的界面相互作用，导致GF在复合材料中的均匀分散。在GF负荷为30 wt%时，与GF30/PA相比，添加18 wt% PNFPI （PNFPI18）的GF增强PA66的熔体平衡扭矩降低了75.0%，极限氧指数（LOI）提高到31.1%，并达到UL-94 V-0等级。同时，与GF30/PA相比，PNFPI18的缺口冲击强度提高了2.16倍，达到10.91 kJ/m²，热偏转温度（HDT）从215.4℃提高到240.6℃。此外，分子动力学（MD）模拟表明，PNFPI增强了GF和PA66之间的分子间相互作用，并通过形成更密集的界面堆栈降低了PNFPI18的分数自由体积（FFV）。本研究为同时提高GF/PA66复合材料和其他高分子复合材料的加工性能、防火安全性和力学性能提供了新的视角。

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引用次数: 0

Efficient enhancement of UV aging resistance in polyvinyl chloride resin using carbon dots 碳点有效增强聚氯乙烯树脂抗紫外线老化性能

IF 7.4 2区化学 Q1 POLYMER SCIENCE

Polymer Degradation and Stability

Pub Date : 2025-11-28 DOI: 10.1016/j.polymdegradstab.2025.111816

Liyi Liu , Mengqi Zhang , Hao Hao , Feng You , Danfeng Zhou , Junyuan Duan , Shenglong Li , Xueliang Jiang

Polyvinyl chloride (PVC) is extensively employed as a cable material in the electric power and construction sectors owing to its affordability and ease of processing. Nonetheless, its susceptibility to ultraviolet (UV) radiation during long-term outdoor use leads to pronounced aging and material degradation. In this work, carbon quantum dots (PCDs), notable for their robust UV absorption and chemical stability, were synthesized via a one-step hydrothermal method, yielding particles with UV absorption center wavelength around 365 nm. These PCDs were first dispersed within a liquid plasticizer to ensure homogeneous distribution before their incorporation into the PVC matrix. Accelerated UV aging tests revealed that PVC composites containing 3% PCDs exhibited remarkable retention in both tensile strength and elongation at break corresponding to 98.6% and 95.6%, respectively-representing significant enhancements compared to unmodified PVC. Surface analyses using scanning electron microscopy (SEM) confirmed a marked reduction in surface cracking upon the addition of PCDs, while Fourier transform infrared spectroscopy (FTIR) demonstrated that this approach effectively inhibits the formation of C=C bonds, thus mitigating free radical-induced degradation. Collectively, these findings validate the proposed anti-aging mechanism of PCDs in PVC. This work introduces a novel approach for utilizing carbon dots as eco-friendly UV absorbers and dispersing carbon dots in soft PVC products without the help of solvent, and provides a practical strategy for enhancing the service life of PVC-based materials under UV exposure.

聚氯乙烯（PVC）由于其价格合理且易于加工，被广泛用作电力和建筑部门的电缆材料。然而，在长期户外使用期间，其对紫外线（UV）辐射的敏感性导致明显的老化和材料降解。本文采用一步水热法合成了具有强紫外吸收和化学稳定性的碳量子点（PCDs），得到了紫外吸收中心波长约为365 nm的粒子。首先将这些PCDs分散在液体增塑剂中，以确保其均匀分布，然后将其掺入PVC基质中。加速紫外线老化试验表明，含有3% PCDs的PVC复合材料在抗拉强度和断裂伸长率方面都有显著的保持，分别为98.6%和95.6%，与未改性的PVC相比有显著的提高。使用扫描电子显微镜（SEM）进行的表面分析证实，添加PCDs后，表面开裂明显减少，而傅里叶变换红外光谱（FTIR）表明，这种方法有效地抑制了C=C键的形成，从而减轻了自由基诱导的降解。总的来说，这些发现证实了聚氯乙烯中PCDs的抗衰老机制。本文介绍了一种利用碳点作为环保紫外线吸收剂的新方法，并在不借助溶剂的情况下将碳点分散在软质PVC产品中，为提高PVC基材料在紫外线照射下的使用寿命提供了一种实用的策略。

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引用次数: 0

Marine-biodegradable alternating copoly(ester-amide)s from (R)-3-hydroxybutyric acid and amino acid with high glass-transition temperature 海洋生物可降解的(R)-3-羟基丁酸与氨基酸的交替共聚物（酯-酰胺），玻璃化转变温度高

IF 7.4 2区化学 Q1 POLYMER SCIENCE

Polymer Degradation and Stability

Pub Date : 2025-11-28 DOI: 10.1016/j.polymdegradstab.2025.111818

Senri Hayashi , Tomohiro Hiraishi , Masayuki Sugimoto , Hideki Abe

Plastic pollution is a serious environmental issue worldwide. Although biodegradable polymers offer a promising solution, improving their physical properties while maintaining biodegradability remains a major challenge. Poly(ester-amide)s combine thermal properties with biodegradability; however, increasing the amide moiety content typically reduces enzymatic degradability, creating a trade-off. In this study, we synthesized the alternating copoly(ester-amide)s with alternating sequence structure of (R)-3-hydroxybutyric acid and amino acids (P[3HB-alt-(amino acid)]s). Four types of amino acids, l-alanine (l-Ala), d-alanine (d-Ala), glycine (Gly), and β-alanine (β-Ala), were used as amino acid moieties, and the thermal properties and biodegradability of the synthesized P[3HB-alt-(amino acid)]s were evaluated. Obtained P[3HB-alt-(amino acid)]s exhibited high glass-transition temperatures (55‒85 °C). The alternating sequence enabled the incorporation of amide units at a 1:1 ratio with ester units without suppressing degradability, which contrasts with conventional poly(ester-amide) designs. Biodegradation tests with seawater showed that P(3HB-alt-l-Ala), P(3HB-alt-Gly), and P(3HB-alt-β-Ala) reached 37‒58 % biodegradation within 60 days based on BOD measurements and were metabolized by marine microorganisms, whereas P(3HB-alt-d-Ala) degraded slowly but generated water-soluble oligomers that microorganisms could utilize. Enzymatic degradation tests with hydrolases demonstrated that PHB depolymerase hydrolyzes ester linkages in all copolymers, while proteinase K selectively degrades l-Ala- and Gly-containing sequences due to stereochemical recognition. These results suggest that controlling the monomer sequence and stereo-configuration is the key to balancing biodegradability and physical properties, providing a strategy for designing sustainable polymers.

塑料污染是一个全球性的严重环境问题。尽管生物可降解聚合物提供了一个很有前途的解决方案，但在保持生物可降解性的同时提高其物理性能仍然是一个主要挑战。聚（酯-酰胺）集热性能与生物降解性于一身；然而，增加酰胺部分含量通常会降低酶的可降解性，从而产生一种权衡。本研究合成了具有(R)-3-羟基丁酸与氨基酸（P[3HB-alt-（氨基酸）]s）交替序列结构的交替共聚物（酯-酰胺）s。以l-丙氨酸（l-Ala）、d-丙氨酸（d-Ala）、甘氨酸（Gly）和β-丙氨酸（β-Ala） 4种氨基酸为氨基酸段，对合成的P[3HB-alt-（氨基酸）]s的热性能和生物降解性进行了评价。得到的P[3HB-alt-（氨基酸）]s具有较高的玻璃化转变温度（55-85℃）。交替序列使酰胺单元与酯单元以1:1的比例结合，而不会抑制降解性，这与传统的聚（酯-酰胺）设计形成对比。海水生物降解试验表明，根据BOD测量，P（3HB-alt-l- ala）、P（3HB-alt- gly）和P（3HB-alt-β-Ala）在60天内生物降解率达到37 - 58%，并被海洋微生物代谢，而P（3HB-alt-d- ala）降解缓慢，但产生可被微生物利用的水溶性低聚物。水解酶的酶降解测试表明，PHB解聚合酶水解所有共聚物中的酯键，而蛋白酶K由于立体化学识别而选择性地降解含有l-Ala和gly的序列。这些结果表明，控制单体序列和立体构型是平衡生物降解性和物理性能的关键，为设计可持续聚合物提供了策略。

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