Polymer Testing最新文献_第9页

Characterization of poly(lactic acid) enhancement via poly(L-lactic acid)/poly(D-lactic acid) stereocomplexation and its influence on material crystallinity and morphology 聚l -乳酸/聚d -乳酸立体络合增强聚乳酸的表征及其对材料结晶度和形貌的影响

IF 6 2区材料科学 Q1 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Polymer Testing

Pub Date : 2025-09-26 DOI: 10.1016/j.polymertesting.2025.108997

Ingrid Trofin , Martin Borůvka , Sabine Hild

Poly(lactic acid) (PLA) is a biobased, biodegradable material that has shown great potential as an alternative to fossil-based polymers, already used in various fields due to its biocompatibility and advantageous physico-chemical properties. However, PLA lacks the thermal stability and impact resistance needed for engineering applications. To this end, the current study proposes a solvent-free methodology for the physical preparation of a PLA stereocomplex (PLA-SC) between enantiomeric poly(_D-lactic acid) and poly(_L-lactic acid), and its use in small amounts as a self-nucleating agent. The strength of the internal hydrogen-bonding (−CH₃ … O=C) within the stereocomplex crystallites was altered by applying three threshold extrusion temperatures, and its influence on crystallinity and morphology was investigated. The crystallinity of PDLLA showed a sixfold increase with the addition of PLA-SC, while the crystallinity of PLLA doubled, as indicated by differential scanning calorimetry (DSC) and corroborated by Raman spectroscopy. The self-nucleation effect of the stereocomplex was observed under polarized optical light microscopy (POM). Atomic force microscopy (AFM) revealed two distinct morphologies correlated to the crystallinity trends recorded, namely spherulites and shish-kebabs, the latter being known as flow-induced, oriented semi-crystalline conformations. The intrinsic crystallization kinetics of each matrix promoted lamellar or fibrillar packing, respectively. The heat deflection temperatures (HDT) also increased with an increase in PLA-SC content for both PDLLA and PLLA matrices. Incorporating very low amounts of PLA-SC into PLA matrices of different optical purities under industrial processing conditions enhanced material properties, crucial for widening the applicability of this bioplastic.

聚乳酸（PLA）是一种生物基、可生物降解的材料，作为化石基聚合物的替代品显示出巨大的潜力，由于其生物相容性和有利的物理化学性质，已经在各个领域得到了应用。然而，PLA缺乏工程应用所需的热稳定性和抗冲击性。为此，本研究提出了一种无溶剂的方法，用于物理制备对映体聚乳酸（d -乳酸）和聚乳酸（l -乳酸）之间的PLA立体配合物（PLA- sc），并将其少量用作自成核剂。三种阈值挤压温度改变了立体配合物内部氢键（−CH3…O=C）的强度，并研究了其对结晶度和形貌的影响。差示扫描量热法（DSC）和拉曼光谱证实，PLA-SC的加入使PDLLA的结晶度提高了6倍，PLLA的结晶度提高了一倍。在偏光显微镜（POM）下观察了立体配合物的自核效应。原子力显微镜（AFM）显示了与记录的结晶度趋势相关的两种不同的形态，即球晶和羊肉串，后者被称为流动诱导的定向半晶构象。每种基体的固有结晶动力学分别促进了层状或纤维状堆积。PDLLA和PLLA基体的热变形温度（HDT）也随PLA-SC含量的增加而升高。在工业加工条件下，将极少量的PLA- sc加入不同光学纯度的PLA基质中，增强了材料性能，这对于扩大这种生物塑料的适用性至关重要。

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引用次数: 0

Innovative supramolecular magnetic magnesium-aluminum LDHs-decorated-carboxymethylcellulose for doxorubicin uptake from aqueous solutions 创新的超分子磁性镁铝ldhs修饰羧甲基纤维素从水溶液中摄取阿霉素

IF 6 2区材料科学 Q1 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Polymer Testing

Pub Date : 2025-09-26 DOI: 10.1016/j.polymertesting.2025.108994

Saja A. Althobaiti , Gehan M. Nabil , Mohamed E. Mahmoud

Doxorubicin drug (DOX) is well-characterized by its high chemical stability with minimum ability to biodegrade. It has been recently characterized as a pollutant in wastewaters. Therefore, the current investigation is devoted to explore the potential recovery of DOX pollutant onto a newly assembled nanocomposite from the combination of carboxymethylcellulose and magnetite with magnesium/aluminum double layered hydroxide (CMC@Fe₃O₄@MgAl-LDHs). Fe, O, C, Mg and Al elements were detected in this nanocomposite providing 44.78, 38.81, 9.12, 4.02 and 3.27 %, respectively. The implementation of CMC@Fe₃O₄@MgAl-LDHs in sportive removal of DOX was monitored under numerous impacting conditions including pH (2.0–11.0), reaction time (2–60 min), nanocomposite dosage (2–60 mg), ionic strength via NaCl (10.0–100.0 mg), DOX initial concentration (1.0–20.0 mg L⁻¹) and reaction temperature (25–60 °C). The pHpzc of CMC@Fe₃O₄@MgAl-LDHs was detected as 5.8 to favoring high adsorptive capture values of DOX near this pH condition. CMC@Fe₃O₄@MgAl-LDHs exhibited excellent stability toward regeneration for five consecutive cycles providing 90.0–96.0 %. Moreover, CMC@Fe₃O₄@MgAl-LDHs exhibited excellent removal capability of DOX from real waters up to 95.0–96.5 % (tap water), 95.5–96.1 % (wastewater) and 81.0–83.9 (sea water). Therefore, it could be concluded from the provided data that the investigated CMC@Fe₃O₄@MgAl-LDHs is a valid and promising adsorbent with lauded potential for significant implementation in DOX recovery from real wastewaters providing high capability and performance with excellent efficiency. Finally, the outcomes from this study approved and lauded the high significance of CMC@Fe₃O₄@MgAl-LDHs owing to its practical potential in real water treatment based on its high adsorption efficiency, regenerability, biodegradability.

阿霉素（DOX）具有较高的化学稳定性和最低的生物降解能力。它最近被定性为废水中的污染物。因此，目前的研究致力于探索将DOX污染物回收到由羧甲基纤维素和磁铁矿与镁/铝双层氢氧化物（CMC@Fe3O4@MgAl-LDHs）组合而成的新组装的纳米复合材料上的可能性。Fe、O、C、Mg和Al的含量分别为44.78%、38.81%、9.12%、4.02和3.27%。在pH（2.0-11.0）、反应时间（2-60 min）、纳米复合材料用量（2-60 mg）、NaCl离子强度（10.0-100.0 mg）、DOX初始浓度（1.0-20.0 mg L - 1）和反应温度（25-60℃）等多种影响条件下，监测CMC@Fe3O4@MgAl-LDHs在运动去除DOX中的实施情况。检测到CMC@Fe3O4@MgAl-LDHs的pHpzc为5.8，有利于DOX在该pH条件下的高吸附捕获值。CMC@Fe3O4@MgAl-LDHs在连续五个循环中表现出优异的再生稳定性，提供90.0 - 96.0%。此外，CMC@Fe3O4@MgAl-LDHs对自来水、废水和海水中DOX的去除率分别为95.0 ~ 96.5%、95.5 ~ 96.1%和81.0 ~ 83.9。因此，从所提供的数据可以得出结论，所研究的CMC@Fe3O4@MgAl-LDHs是一种有效且有前途的吸附剂，具有良好的潜力，可以在实际废水中回收DOX，具有高性能和卓越的效率。最后，本研究的结果认可并赞扬了CMC@Fe3O4@MgAl-LDHs的高吸附效率、可再生性、可生物降解性在实际水处理中的应用潜力。

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引用次数: 0

Eco-friendly polyurethane foams enriched with sodium hydroxide modified wastepaper filler 富含氢氧化钠改性废纸填料的环保型聚氨酯泡沫

IF 6 2区材料科学 Q1 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Polymer Testing

Pub Date : 2025-09-26 DOI: 10.1016/j.polymertesting.2025.108989

Sylwia Makowska , Dawid Szymborski , Natalia Sienkiewicz , Agnė Kairytė , Piotr Pospiech , Przemysław Rybiński , Giedrius Balčiūnas , Renata Boris

In the presented study, rigid polyurethane foams were modified with a filler in the form of beech wood pulp modified with sodium hydroxide solution. The effects of 0.2, 0.2, 1.2, 2.3, 3.5 and 4.7 wt% of the filler on the performance of the foams were investigated. The best thermo-mechanical properties were characterised by composites containing 3.5 wt% of filler. The samples were characterised by increased damping capacity after thermo-oxidative ageing, lower water absorption (about 38 %) and reduced thermal conductivity. The addition of a thermally unstable cellulose filler did not impair the thermal stability of the PU. The developed compositions confirm the possibility of using paper as a modifier for rigid polyurethane foams. The additive strengthens the composites, protects them from the effects of thermo-oxidative ageing and makes them suitable for use in higher humidity environments.

在本研究中，以氢氧化钠溶液改性的山毛榉木浆为填料对硬质聚氨酯泡沫进行改性。研究了0.2、0.2、1.2、2.3、3.5、4.7 wt%的填料对泡沫材料性能的影响。填充量为3.5 wt%的复合材料具有最佳的热机械性能。样品的特点是热氧化老化后阻尼能力增加，吸水率降低（约38%），导热系数降低。添加热不稳定的纤维素填料不影响PU的热稳定性。所开发的组合物证实了用纸作为硬质聚氨酯泡沫改性剂的可能性。添加剂增强复合材料，保护它们免受热氧化老化的影响，使它们适合在较高湿度的环境中使用。

引用次数: 0

Improved electrical properties, hydrophobicity, and degradability of ortho-vanillin-based epoxy resin: Roles of Schiff base 改善邻香草素基环氧树脂的电性能、疏水性和可降解性：希夫碱的作用

IF 6 2区材料科学 Q1 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Polymer Testing

Pub Date : 2025-09-24 DOI: 10.1016/j.polymertesting.2025.108992

Xiao Peng , Xuetong Zhao , Tingyue Dong , Yuan Yuan , Li Cheng , Lijun Yang , Ruijin Liao

Conventional diglycidyl ether of bisphenol A epoxy resins (DGEBA) are made from non-renewable fossil resources, which caused severe resource waste and environmental issues. It is of great importance to develop degradable epoxy resins with excellent physicochemical and electrical properties. In this work, a novel vanillin-based epoxy resin (VEP) with Schiff base bond is synthesized from Ortho-vanillin (OVA) and L-phenylalanine (PHE) through a two-step procedure. After cured with 4, 4′-diaminodiphenylmethane (DDM), the vanillin-based epoxy resin (VEP/DDM) exhibits a high char yield of 31.15 %, and 110 % enhancement in storage modulus comparing to DGEBA/DDM. Meanwhile, VEP/DDM presents excellent electrical properties with breakdown strength of 33.16 kV/mm, dielectric constant of 4.00 and dielectric loss of 0.0059 at 50 Hz, respectively. Furthermore, the degradable Schiff base and hydrophobic groups on the side chain of PHE enable the VEP/DDM with good acid-catalytic degradation and hydrophobic properties. This work provides a new route for fabricating bio-based epoxy resins with promising physicochemical and electrical performance in practical engineering applications.

传统的双酚A环氧树脂二缩水甘油酯（DGEBA）是由不可再生的化石资源制成的，造成了严重的资源浪费和环境问题。开发具有优良理化性能和电学性能的可降解环氧树脂具有重要意义。本文以邻香草醛（OVA）和l -苯丙氨酸（PHE）为原料，通过两步法合成了一种具有席夫碱键的新型香草基环氧树脂（VEP）。用4,4′-二氨基二苯甲烷（DDM）固化后，香草素基环氧树脂（VEP/DDM）的炭产率达到31.15%，存储模量比DGEBA/DDM提高了110%。同时，VEP/DDM具有优异的电学性能，在50 Hz时击穿强度为33.16 kV/mm，介电常数为4.00，介电损耗为0.0059。此外，PHE侧链上可降解的席夫碱和疏水性基团使VEP/DDM具有良好的酸催化降解和疏水性。本研究为制备具有良好理化性能和电学性能的生物基环氧树脂提供了一条新的途径。

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引用次数: 0

Zn-Co nanoferrites incorporated polysulfone nanofiltration membranes for wastewater treatment 锌钴纳米铁氧体掺入聚砜纳滤膜用于废水处理

IF 6 2区材料科学 Q1 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Polymer Testing

Pub Date : 2025-09-24 DOI: 10.1016/j.polymertesting.2025.108993

Kiran Shahzadi , Muhammad Sarfraz , Muneerah Alomar , Maryam Al Huwayz , Aqib Riaz , M.A. Mujtaba , Muhammad Nasir Bashir , Jana Petrů

Exacerbating challenges of providing safe environment and drinking water to humanity can be efficiently managed via membrane technology. Nanomaterials-impregnated polymer membranes find versatile applications in the removal of heavy metals from contaminated water. Owing to their outstanding mesoporous properties, high surface area, and good chemical and thermal resistance, the nanoparticles of Zn-Co nanoferrites (Zn_1-xCo_xFe₂O₄) were imbedded into polysulfone (PSF) matrix to concoct mixed-matrix membranes using wet phase inversion process. Hydrothermally synthesized Zn_1-xCo_xFe₂O₄ (x = 0.2, 0.4, 0.6, 1.0) nanoferrite particles of approximately 29–45 nm size in unannealed and annealed state were doped in PSF matrix to assess the effects of nanoferrites annealing on separation performance of resulting membranes. A thorough analysis was conducted to evaluate nanoferrites doping effect on membranes chemical structure, morphology, mechanical strength, wettability and microporous properties using FTIR, optical microscopy, UTM, Goneometer and porosity tester. Compared to pristine PSF membrane, water desalination performance of nanoferrites-filled membranes were significantly improved on doping nanoferrites of different grades.

为人类提供安全环境和饮用水的日益严峻的挑战可以通过膜技术有效地管理。纳米材料浸渍聚合物膜在去除污染水中的重金属方面有着广泛的应用。由于具有优异的介孔性能、高的比表面积和良好的耐化学性和耐热性，采用湿相转化工艺将Zn-Co纳米铁氧体（Zn1-xCoxFe2O4）纳米颗粒嵌入到聚砜（PSF）基体中制备混合基质膜。将水热合成的Zn1-xCoxFe2O4 （x = 0.2, 0.4, 0.6, 1.0）在未退火和退火状态下约29-45 nm的纳米铁素体颗粒掺杂到PSF基体中，以评估纳米铁素体退火对所得膜分离性能的影响。采用红外光谱（FTIR）、光学显微镜、UTM、Goneometer、孔隙率测试仪等分析了纳米铁氧体掺杂对膜的化学结构、形貌、机械强度、润湿性和微孔性能的影响。与原始PSF膜相比，掺杂不同等级纳米铁氧体后，纳米铁氧体填充膜的海水淡化性能显著提高。

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引用次数: 0

Characterisation of the void volume loss of dynamically loaded structured polyurethane composites using viscoelastic modelling 用粘弹性模型表征动态加载结构聚氨酯复合材料的空隙体积损失

IF 6 2区材料科学 Q1 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Polymer Testing

Pub Date : 2025-09-19 DOI: 10.1016/j.polymertesting.2025.108984

Patrick Wegele , L. Daniel Söderberg

A calculation method has been derived to predict the void volume loss of dynamically loaded structured composites commonly used as press belts in paper manufacturing. The method is based on a viscoelastic model that uses two serial generalised three-parameter Maxwell models and allows for predicting the void volume loss as a function of the applied external load and load rate. Optical verification of the void volume losses revealed that the method accurately calculates these volume losses that appear in the structure due to viscoelastic compression. Applying it to different composite specimen types makes it possible to quantify the influence of matrix material formulation, geometrical structure, temperature and saturation conditions on the void volume loss of dynamically loaded composites. As a result, the matrix material formulation of the polyurethane matrix is identified as the key parameter influencing the void volume loss.

导出了一种预测造纸中常用的动载结构复合材料压带的空隙体积损失的计算方法。该方法基于粘弹性模型，该模型使用了两个连续的广义三参数Maxwell模型，可以预测孔隙体积损失作为施加的外部载荷和载荷率的函数。对孔隙体积损失的光学验证表明，该方法准确地计算了由于粘弹性压缩而出现在结构中的体积损失。将其应用于不同的复合材料试样类型，可以量化基体材料配方、几何结构、温度和饱和条件对动载复合材料空隙体积损失的影响。结果表明，聚氨酯基体的基体材料配方是影响空隙体积损失的关键参数。

引用次数: 0

Development of a tunable test method for characterizing friction-induced squeak noise in automotive interior plastics 汽车内饰件塑料摩擦噪声可调试验方法的研究

IF 6 2区材料科学 Q1 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Polymer Testing

Pub Date : 2025-09-17 DOI: 10.1016/j.polymertesting.2025.108991

Jun Young Yoon , Sang Min Lee , Youjin Park , Kyung-Woo Lee , Daeun Sung , Seongho Yoon , Byoung-Ho Choi

The emergence of low-noise vehicles, such as electric and hydrogen-powered cars, has increased the perceptibility of minor noises—commonly referred to as buzz, squeak, and rattle—which can significantly influence consumer perception and satisfaction. Among these, squeak noise arises from dynamic frictional interactions between contacting components and is highly sensitive to material properties and environmental conditions. However, existing commercial testing systems with fixed structural stiffness are inadequate for evaluating the friction-induced noise behaviors of various polymer combinations under diverse conditions. To overcome these limitations, a novel test apparatus was developed with adjustable system stiffness and frictional speed, alongside a corresponding evaluation methodology. This setup enables detailed analysis of friction-induced noise characteristics, including frequency, amplitude, and vibration acceleration level (VAL). Experiments were performed using three polymeric materials—polycarbonate (PC), polyoxymethylene (POM), and a polypropylene compound (PP-TDGX)—across four sliding speeds and four stiffness settings. A bandpass filter was applied to eliminate background noise from the acquired signals, and time-domain feature extraction was used to quantify the frequency and amplitude of friction-induced oscillations. Additionally, vibration analysis based on VAL was conducted to assess the severity of frictional noise. The results demonstrate that the tribological interactions between polymer pairs vary significantly with changes in sliding speed and system stiffness. The proposed testing method and equipment offer a more accurate and flexible approach to characterizing friction-induced noise in polymeric materials, thereby supporting more effective material selection for automotive interior applications and potentially reducing both noise issues and development costs.

低噪音车辆的出现，如电动和氢动力汽车，增加了对小噪音的感知——通常被称为嗡嗡声、吱吱声和嘎嘎声——这可以显著影响消费者的感知和满意度。其中，吱吱噪声产生于接触部件之间的动态摩擦相互作用，对材料性能和环境条件高度敏感。然而，现有的固定结构刚度商用测试系统不足以评估各种聚合物组合在不同条件下的摩擦噪声行为。为了克服这些限制，开发了一种具有可调节系统刚度和摩擦速度的新型测试装置，以及相应的评估方法。这种设置可以详细分析摩擦引起的噪声特性，包括频率、振幅和振动加速度水平（VAL）。实验使用三种聚合物材料——聚碳酸酯（PC）、聚甲醛（POM）和聚丙烯化合物（PP-TDGX）——在四种滑动速度和四种刚度设置下进行。采用带通滤波器消除采集信号中的背景噪声，并利用时域特征提取量化摩擦振荡的频率和幅度。此外，还进行了基于VAL的振动分析，以评估摩擦噪声的严重程度。结果表明，聚合物对之间的摩擦学相互作用随着滑动速度和系统刚度的变化而发生显著变化。所提出的测试方法和设备为表征聚合物材料中的摩擦噪声提供了更准确、更灵活的方法，从而为汽车内饰应用提供更有效的材料选择，并有可能降低噪声问题和开发成本。

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引用次数: 0

Optimizing p-aramid copolymer superfibers: The synergistic effect of solution rheology and fiber structure 对芳纶共聚物超纤维的优化：溶液流变与纤维结构的协同效应

IF 6 2区材料科学 Q1 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Polymer Testing

Pub Date : 2025-09-16 DOI: 10.1016/j.polymertesting.2025.108987

Jaegeun Lyu , Hyeonjeong Kim , Min Woo Kim , Juyoung Kim , Howon Choi , Donghoon Lee , Daeyoung Lim , Ji Ho Youk , Youngho Eom , Han Gi Chae

Para-aramid (p-aramid) fibers have gained significant attention in lightweight vehicle and optical cable industries. However, the use of harsh sulfuric acid-based processing limits their widespread adoption. As a promising alternative, p-aramid copolymer (p-AC) offers improved processability while maintaining comparable properties. In this study, p-AC superfibers incorporating 3,4′-oxydianiline (3,4′-ODA) monomers were successfully fabricated through optimized manufacturing processes spanning from solution preparation to fiber property enhancement. The homogeneity of spinning solutions, determined by polymerization conditions, serves as a key factor governing fiber structure and properties. Three p-AC solutions with varying rheological homogeneities, classified as low (L), moderate (M), and high (H), exhibited Cole-Cole plot slopes of 1.12, 1.34, and 1.65, respectively. A higher solution homogeneity enabled greater draw ratios, leading to more compact and well-aligned fiber microstructures. Consequently, as the homogeneity increased, the fiber crystallinity and orientation factor increased from 56.1 % and 0.923 to 62.2 % and 0.968, respectively. Notably, the p-AC-H fibers exhibited tensile modulus and strength of 82.4 and 3.1 GPa, respectively, representing 11.2 % and 41.0 % increases compared to those of p-AC-L fibers (74.1 and 2.2 GPa, respectively). These findings establish a direct correlation between solution homogeneity and fiber performance, providing a theoretical background for the precise design of high-performance superfibers.

对芳纶（p-芳纶）纤维在轻型汽车和光缆行业中得到了广泛的关注。然而，使用苛刻的硫酸基处理限制了它们的广泛采用。作为一种很有前途的替代品，对芳纶共聚物（p-AC）在保持类似性能的同时，提供了更好的可加工性。在本研究中，通过优化从溶液制备到纤维性能增强的制造工艺，成功制备了含有3,4 ' -氧化二苯胺（3,4 ' -ODA）单体的对ac超纤维。聚合条件决定纺丝溶液的均匀性，是决定纤维结构和性能的关键因素。三种具有不同流变均质性的p-AC溶液，分为低(L)、中(M)和高(H)，其Cole-Cole图斜率分别为1.12、1.34和1.65。较高的溶液均匀性使拉伸比更大，从而导致更紧凑和排列良好的纤维微结构。因此，随着均匀性的提高，纤维结晶度和取向因子分别从56.1%和0.923提高到62.2%和0.968。值得注意的是，p-AC-H纤维的拉伸模量和强度分别为82.4和3.1 GPa，与p-AC-L纤维（分别为74.1和2.2 GPa）相比，分别提高了11.2%和41.0%。这些发现建立了溶液均匀性与纤维性能之间的直接关联，为高性能超纤维的精确设计提供了理论背景。

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引用次数: 0

From process to performance: Fused Granular Fabrication of Flax/PP biocomposites 从工艺到性能：亚麻/PP生物复合材料的熔融颗粒制造

IF 6 2区材料科学 Q1 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Polymer Testing

Pub Date : 2025-09-16 DOI: 10.1016/j.polymertesting.2025.108986

Baoxing Wang , Pierre-Antoine Adragna , Guillaume Montay , Guang Yang , Siyu Zhou

This study explores the influence of Fused Granular Fabrication (FGF) parameters on the mechanical performance and microstructural features of flax fiber-reinforced polypropylene (Flax/PP) biocomposites. Layer height, nozzle temperature, and printing orientation were systematically varied, and their effects were analyzed using tensile testing, Digital Image Correlation (DIC), Scanning Electron Microscopy (SEM), and Differential Scanning Calorimetry (DSC). Results show that a layer height of 0.6 mm provides an optimal compromise between mechanical properties, printing efficiency, and process stability, with performance statistically similar to 0.4 mm but superior to larger layer heights (≥0.8 mm). Nozzle temperature exhibited a non-monotonic effect: insufficient fusion and porosity at 170–190 °C reduced strength, while improved interfacial bonding at 210 °C yielded the best properties, followed by degradation at 220 °C due to fiber oxidation and reduced crystallinity. Printing orientation strongly influenced tensile behavior, with ±45° delivering the most uniform stress distribution and highest strength, whereas 90° showed poor interlayer bonding. Overall, FGF enables the fabrication of natural fiber biocomposites with competitive strength-to-weight performance. These findings demonstrate the potential of Flax/PP composites for sustainable engineering applications in automotive and construction sectors, while providing guidelines for further optimization and broader use.

本研究探讨了熔融颗粒制备（FGF）参数对亚麻纤维增强聚丙烯（亚麻/PP）生物复合材料力学性能和微观结构特征的影响。通过拉伸测试、数字图像相关（DIC）、扫描电镜（SEM）和差示扫描量热法（DSC）分析了层高、喷嘴温度和打印方向的变化对材料的影响。结果表明，0.6 mm的层高在力学性能、打印效率和工艺稳定性之间提供了最佳的折衷，其性能与0.4 mm的层高相似，但优于较大的层高（≥0.8 mm）。喷嘴温度表现出非单调效应：在170-190°C时，熔合不足和孔隙率降低，强度降低，而在210°C时，界面结合改善，性能最佳，随后在220°C时，由于纤维氧化和结晶度降低而降解。印刷方向对拉伸性能有很大影响，±45°印刷方向的应力分布最均匀，强度最高，而90°印刷方向的层间结合最差。总的来说，FGF使天然纤维生物复合材料的制造具有竞争力的强度重量比性能。这些发现证明了亚麻/PP复合材料在汽车和建筑领域可持续工程应用的潜力，同时为进一步优化和更广泛的应用提供了指导。

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引用次数: 0

Exploring potential correlation between mechanical and physicochemical properties of aramid fibers under acid/alkali exposure 探讨芳纶纤维在酸碱作用下力学性能与理化性能的潜在相关性

IF 6 2区材料科学 Q1 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Polymer Testing

Pub Date : 2025-09-16 DOI: 10.1016/j.polymertesting.2025.108988

Xiarui Fan , Xinwei Zhou , Peng Ren

Aramid fiber products have been widely applied in harsh environments due to their excellent performances. The changes in mechanical properties of fibers under acid/alkali exposure and their correlation with physicochemical properties has been an interest point for the materials application. In this study, the tensile strength and failure strain of fibers were analyzed under different acid/alkali exposure to characterize the changes in mechanical properties. Meanwhile, the physicochemical properties of fibers including micromorphology, phase structure, and functional groups were characterized by scanning electron microscope, X-ray diffraction and attenuated total reflection-Fourier transform infrared spectroscopy. The results show that the tensile strength retention ratios firstly increased and then decreased with the increase in treatment time at the same treatment concentration. Multiple characterization results indicated that the physicochemical properties of the treated fibers altered significantly, including surface morphology damage, crystallinity increasing, and the hydrolysis of amide bonds in molecular structure. The joint results show that the changes in tensile strength and failure strain of the treated fibers were attributed to the antagonistic result of the reinforced effect of the increased crystallinity and the attenuated effect of hydrolytic degradation. The obtained results can provide a theoretical support to improve our understanding of the correlation between the alterations of mechanical properties and physicochemical properties induced by acid/alkali exposure in harsh environments. This understanding would also help better to develop the composite materials based on the chemically modified fibers.

芳纶纤维制品以其优异的性能在恶劣环境中得到了广泛的应用。纤维在酸/碱作用下力学性能的变化及其与物理化学性能的关系一直是材料应用的研究热点。本研究通过分析不同酸/碱作用下纤维的抗拉强度和破坏应变来表征其力学性能的变化。同时，利用扫描电镜、x射线衍射和衰减全反射-傅里叶变换红外光谱对纤维的微观形貌、相结构和官能团等理化性质进行了表征。结果表明：在相同处理浓度下，随着处理时间的增加，拉伸强度保持比先增大后减小；多重表征结果表明，处理后的纤维的理化性质发生了显著变化，包括表面形貌破坏、结晶度增加以及分子结构中酰胺键的水解。结果表明，处理后纤维的抗拉强度和破坏应变的变化是结晶度增加的增强作用和水解降解的减弱作用的拮抗结果。所得结果可为进一步认识恶劣环境中酸/碱对材料力学性能和理化性能变化的影响提供理论支持。这也将有助于更好地开发基于化学改性纤维的复合材料。

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引用次数: 0