今日更新：Composite Structures 3 篇，Composites Part A: Applied Science and Manufacturing 1 篇，Composites Part B: Engineering 8 篇，Composites Science and Technology 4 篇Composite StructuresDynamic mechanical behavior of CNT-reinforced epoxy under medium-strain rate: A comparative studyReza Yazdanparast, Roham Rafiee, Hamed Kalhori, Bing Lidoi:10.1016/j.compstruct.2024.118343中应变速率下 CNT 增强环氧树脂的动态力学行为：比较研究Carbon nanotubes (CNTs) are generally recognized as one of the most effective fillers to improve the properties of polymeric materials. Subjected to dynamic loading, polymer-based materials often exhibit high strain rate sensitivity. This research investigates the effectiveness of CNTs fillers on the mechanical properties of an epoxy resin at low to medium strain rates through conducting a comparative experimental study. Performing tensile and shear tests, the elastic modulus and strength properties of CNT/epoxy and pure epoxy resin are measured at different strain rates. By proposing an empirical logarithmic relationship, the prediction of dynamic elastic modulus and strength properties at any desired low to medium strain rate is facilitated. For measuring the dynamic fracture toughness of CNT/epoxy and pure epoxy resin at medium strain rate, the instrumented charpy impact test based on the Dynamic Key Curves (DKC) method is used. Experimental measurements still imply on significant enhancements in axial and shear properties and also dynamic fracture toughness up to medium strain rates of 150 s−1 by adding small portion of CNTs.碳纳米管（CNT）被公认为是改善聚合物材料性能的最有效填充物之一。在动态加载条件下，聚合物基材料通常表现出较高的应变速率敏感性。本研究通过对比实验研究了 CNTs 填料在中低应变速率下对环氧树脂机械性能的影响。通过拉伸和剪切试验，测量了 CNT/环氧树脂和纯环氧树脂在不同应变速率下的弹性模量和强度特性。通过提出经验对数关系，有助于预测任何所需的中低应变速率下的动态弹性模量和强度特性。为了测量 CNT/环氧树脂和纯环氧树脂在中等应变速率下的动态断裂韧性，使用了基于动态关键曲线 (DKC) 方法的仪表式夏比冲击试验。实验测量结果表明，通过添加少量 CNT，轴向和剪切性能以及动态断裂韧性在 150 s-1 的中等应变速率下仍有显著提高。Adaptive multi-patch isogeometric analysis with truncated hierarchical B-splines in isotropic/orthotropic mediaLin Wang, Tiantang Yu, Weihua Fang, Tinh Quoc Buidoi:10.1016/j.compstruct.2024.118326在各向同性/各向异性介质中使用截断分层 B 样条进行自适应多补丁等值分析We present an adaptive multi-patch isogeometric analysis on the basis of truncated hierarchical B-splines (THB-splines) for solving two-dimensional complex isotropic/orthotropic elasticity. The THB-splines have local refinement property and their basis functions exhibit linear independence, so these features are highly applicable for adaptive isogeometric analysis. Guided by a posterior error estimator based on stress recovery, the adaptive algorithm is utilized in isogeometric analysis. In order to further extend the proposed method to solve complex geometry problems, the multi-patch technique is adopted to achieve exact modeling with Nitsche’s method as a multi-patch coupling approach. An isotropic numerical example with exact analytical solutions and three orthotropic numerical examples are presented to verify the effectiveness and accuracy of the developed method. Numerical solutions show that the developed adaptive isogeometric analysis method has high computational efficiency.我们提出了一种基于截断分层 B 样条（THB 样条）的自适应多斑等值线分析方法，用于求解二维复杂的各向同性/各向异性弹性问题。THB 样条具有局部细化特性，其基函数表现出线性独立性，因此这些特点非常适用于自适应等距分析。在基于应力恢复的后验误差估计器的指导下，自适应算法被用于等距测量分析。为了进一步扩展所提出的方法以解决复杂的几何问题，采用了多补丁技术，以 Nitsche 方法作为多补丁耦合方法实现精确建模。为了验证所开发方法的有效性和准确性，介绍了一个具有精确分析解的各向同性数值示例和三个正交各向同性数值示例。数值解表明，所开发的自适应等距分析方法具有很高的计算效率。Viscoelasticity and impact behaviour of green epoxy bio-composites made of date palm leafletsA. Bezazi, N. Bouhemame, P.N.B. Reis, P. Santos, H. Boumediri, F. Scarpadoi:10.1016/j.compstruct.2024.118347枣椰叶制成的绿色环氧生物复合材料的粘弹性和冲击行为Natural fibres can replace traditional synthetic fibre composites in applications for which sustainability is a critical aspect. Elghas date palm leaflets in their natural state and with handwoven fabric reinforcements—the latter from customary and regional carpet productions—are included into new bio-based composites that are produced and characterized in this work. The two classes of bio-composites have the same weight fraction in terms of reinforcement. The date palm leaflets reinforcements are dispersed in a green resin matrix. Bio-composites reinforced with leaflets tree have twice the static bending strength than those with leaflets fabric reinforcements. The viscoelastic behaviour of those bio-composites shows an opposite trend, with the laminates reinforced with leaflets fabric being the least sensitive. For an impact energy of 3 J, the strength of bio-composites with leaflets fabric is double than the analogous value shown by bio-composites with leaflets tree. The impact strength however increases by 4.7 times for lower impact energies of 1 J. The results shown here further demonstrate the possibility of developing bio-composites from agro-industrial products, waste, and local textile traditions for secondary structural applications.天然纤维可以取代传统的合成纤维复合材料，用于可持续性要求极高的应用领域。本研究将天然状态下的额尔古纳枣椰叶和手织织物加固材料（后者来自传统和地区地毯生产）纳入新型生物基复合材料中，并对其进行了生产和表征。就增强材料而言，这两类生物复合材料的重量比例相同。枣椰树小叶增强材料分散在绿色树脂基体中。用小叶树加固的生物复合材料的静态抗弯强度是用小叶织物加固的生物复合材料的两倍。这些生物复合材料的粘弹性行为显示出相反的趋势，用小叶织物增强的复合材料最不敏感。在 3 J 的冲击能量下，使用小叶织物的生物复合材料的强度是使用小叶树的生物复合材料的两倍。然而，在 1 J 的较低冲击能量下，冲击强度增加了 4.7 倍。这里显示的结果进一步证明了利用农用工业产品、废物和当地传统纺织品开发二次结构用生物复合材料的可能性。Composites Part A: Applied Science and ManufacturingPoly(butylene succinate) reinforced by small amount of grafted nanofibrillated bacterial cellulose: Toughness variability based on nanocomposites preparation methodHamidah binti Hashim, Xiaochao Xia, Hiroshi Kani, Shuichiro Seno, Feng Li, Takuya Isono, Takuya Yamamoto, Hirofumi Tani, Toshifumi Satoh, Kenji Tajimadoi:10.1016/j.compositesa.2024.108341用少量接枝纳米纤化细菌纤维素增强聚丁二酸丁二醇酯：基于纳米复合材料制备方法的韧性变化Polybutylene succinate (PBS) is a promising biodegradable polymer; however, its low mechanical performance limits its application. To address this issue, long fiber length nanofibrillated bacterial cellulose (HP-NFBC), produced by a bottom-up process using cellulose-producing bacterium and hydroxypropyl cellulose (HPC) as a dispersing agent was used as reinforcement agent. Hydrophobic moieties were grafted on HP-NFBC surface to increase surface compatibility. Nanocomposites prepared by both solvent casting and melt-kneading were evaluated. By solvent casting, the addition of 0.25 wt% of grafted HP-NFBC increased the toughness by 212%. Melt-kneading revealed an increase in flexural strength and young’s modulus. More evident improvement was observed when the nanocomposites were annealed, and the ultimate strength increased by 113 % at 2 wt% of grafted HP-NFBC incorporation. Great increased in toughness were achieved only by small incorporation of grafted HP-NFBC. Additionally, compost biodegradation tests were conducted to confirm that the nanocomposites had biodegradability similar to that of PBS.聚丁二酸丁二醇酯（PBS）是一种前景广阔的生物可降解聚合物，但其较低的机械性能限制了它的应用。为解决这一问题，使用纤维素生产细菌和羟丙基纤维素（HPC）作为分散剂，通过自下而上的工艺生产出长纤维纳米纤维素（HP-NFBC）作为增强剂。在 HP-NFBC 表面接枝疏水分子，以增加表面相容性。对通过溶剂浇注和熔融捏合两种方法制备的纳米复合材料进行了评估。通过溶剂浇铸，添加 0.25 wt% 的接枝 HP-NFBC 使韧性提高了 212%。熔融捏合显示了抗弯强度和青年模量的增加。对纳米复合材料进行退火处理时，观察到了更明显的改善，当接枝 HP-NFBC 的添加量为 2 wt% 时，极限强度提高了 113%。只有加入少量接枝 HP-NFBC 时，韧性才会大幅提高。此外，还进行了堆肥生物降解测试，证实纳米复合材料具有与 PBS 相似的生物降解性。Composites Part B: EngineeringLignin: a multifunctional and sustainable photothermal material for solar-driven thermoelectric generation and desalinationQizhao Shao, Yiting Li, Zhicheng Liang, Zhao Chen, Anqi Xu, Xueqing Qiu, Dafeng Zhengdoi:10.1016/j.compositesb.2024.111694 木质素：用于太阳能热发电和海水淡化的多功能可持续光热材料The abundant aromatic ring structure and a large number of oxygen-containing functional groups in the lignin offer the possibility of achieving excellent photothermal conversion ability and modulating the synthesis of metal nanoparticles. Herein, three kinds of the lignin with different functional group content were employed to investigate the potential influence on the particle size and the solution stability of the CuS through two reaction pathways. The result of various characterizations indicated that the higher the oxygen-containing functional group content (4.83 mmol/g) of lignin, the smaller the size of CuS nanoparticles (∼80 nm) in solution. And the smaller and homogeneously dispersed CuS offered a higher surface temperature for the solar-driven heat-generating materials. The regulation mechanism was also proposed based on the result of the molecular dynamics simulation and DFT calculation. Subsequently, the photothermal film (Route2 DTAL-PVA-30) and solar-driven aerogel evaporator (Route2 DTAL-AG3) were successfully prepared using the lignin-guided stabilization solution of CuS nanoparticles. The photothermal conversion efficiency of 49.43% and the equilibrium voltage of 266 mV can be achieved by the Route2 DTAL-PVA-30 under 1 sun using a thermoelectric generator. The Route2 DTAL-AG3 exhibited promising salt-rejecting property and outstanding acid and alkali resistance performance, reaching an evaporation rate of up to 1.93 kg/(m2 h) in the 3.5 wt% seawater under 1sun. This work may provide a novel strategy to realize the regulatory role of lignin in the metal synthesis and achieve the high value-added applications of the lignin.木质素中丰富的芳香环结构和大量的含氧官能团为实现优异的光热转化能力和调节金属纳米粒子的合成提供了可能。本文采用三种不同官能团含量的木质素，通过两种反应途径研究其对 CuS 粒径和溶液稳定性的潜在影响。各种表征结果表明，木质素中含氧官能团含量越高（4.83 mmol/g），CuS 纳米粒子在溶液中的尺寸越小（∼80 nm）。而更小且均匀分散的 CuS 为太阳能驱动的发热材料提供了更高的表面温度。根据分子动力学模拟和 DFT 计算的结果，还提出了调节机制。随后，利用木质素引导的 CuS 纳米颗粒稳定液成功制备了光热薄膜（Route2 DTAL-PVA-30）和太阳能驱动气凝胶蒸发器（Route2 DTAL-AG3）。利用热电发生器，Route2 DTAL-PVA-30 可在 1 个太阳下实现 49.43% 的光热转换效率和 266 mV 的平衡电压。Route2 DTAL-AG3 表现出良好的拒盐性能和出色的耐酸碱性能，在 1 个太阳下，其在 3.5 wt% 海水中的蒸发率高达 1.93 kg/(m2 h)。这项工作为实现木质素在金属合成中的调控作用和木质素的高附加值应用提供了一种新的策略。An Osteoimmunomodulatory Ca2+/Zn2+-Doped Scaffold Promotes M2 Macrophage Polarization via the Src-Mediated Chemoking Signaling Pathway to Enhance OsteoinductionKai Wang, Kai Jiang, Chuan Luo, Xuanhe You, Hui-Yuan Shen, Diwei Wu, Fu-Wen Huang, Lingli Li, Shishu Huang, Jia-Zhuang Xu, Zhong-Ming Lidoi:10.1016/j.compositesb.2024.111653 掺杂 Ca2+/Zn2+ 的骨免疫调节支架通过 Src 介导的化疗信号通路促进 M2 巨噬细胞极化，从而增强骨诱导作用Bone defects disrupt physiological functions of various cells including immune cells, osteoblasts, and osteoclasts. Restoring the coordinative effects of cells between osteogenesis and the immune microenvironment is essential and challenging for bone regeneration. Here, we developed an osteoimmunomodulatory Ca2+/Zn2+ doped polycaprolactone electrospinning scaffold to enhance osteoinduction by modulating the polarization of macrophages. To endow nucleation sites for Ca2+ deposition, epitaxial crystallization was conducted to yield the conformal nano-lamellae on the scaffold surface. The Zn2+ was then embedded into the mineralized scaffold via an ion exchange method. Such an approach remarkably improved the deposition amount of Ca2+ and Zn2+, showing a highly sustained iron release. This hybrid scaffold was capable to regulate the M2-type polarization of macrophages, forming an immune-osteogenic microenvironment. As a result, the osteogenic differentiation of rat bone marrow mesenchymal stem cells (rBMSCs) was enhanced via activating the Src-mediated chemoking signaling pathway as verified by gene sequencing, western blotting, and polymerase chain reaction results. In vivo evaluation further demonstrated that the hybrid scaffold remarkably promoted the bone regeneration in a critical-sized rat cranial defect. Compared to the control group, the bone volume/total volume (BV/TV) of the hybrid scaffold group was increased by 2.6 times. This work provides a feasible strategy for fabricating bone repair substitutes that regulate the bone immune microenvironment and coordinate multicellular functions.骨缺损会破坏包括免疫细胞、成骨细胞和破骨细胞在内的各种细胞的生理功能。恢复细胞在成骨和免疫微环境之间的协调作用对骨再生至关重要，也极具挑战性。在此，我们开发了一种骨免疫调节掺杂 Ca2+/Zn2+ 的聚己内酯电纺支架，通过调节巨噬细胞的极化来增强骨诱导。为了赋予 Ca2+ 沉积的成核位点，在支架表面进行了外延结晶，生成了保形纳米薄片。然后通过离子交换法将 Zn2+ 嵌入矿化支架。这种方法显著提高了 Ca2+ 和 Zn2+ 的沉积量，并显示出高度持续的铁释放。这种混合支架能够调节巨噬细胞的 M2 型极化，形成免疫抑制性微环境。因此，大鼠骨髓间充质干细胞（rBMSCs）的成骨分化通过激活 Src 介导的趋化信号通路得到了增强，基因测序、Western 印迹和聚合酶链反应结果均证实了这一点。体内评估进一步证明，混合支架显著促进了临界大小大鼠颅骨缺损的骨再生。与对照组相比，混合支架组的骨体积/总体积（BV/TV）增加了 2.6 倍。这项工作为制造能调节骨免疫微环境和协调多细胞功能的骨修复替代物提供了一种可行的策略。Supra-alveolar bone regeneration: Progress, challenges, and future perspectivesAjay Shakya, Yingzi Li, Nai-wen Chang, Xiaohua Liudoi:10.1016/j.compositesb.2024.111673齿槽上骨再生：进展、挑战和未来展望Periodontitis is a highly prevalent disease that damages the supporting tissues of a tooth, including the alveolar bone. Alveolar bone loss owing to periodontitis is broadly categorized as supra-alveolar and intra-alveolar bone loss. In intra-alveolar bone loss, the defect has an angular or oblique orientation to the long axis of the tooth in an apical direction. In contrast, the defect is perpendicular to the long axis of the tooth in supra-alveolar bone loss. Unlike intra-alveolar bone defects, supra-alveolar bone defects lack supporting adjacent space, which makes supra-alveolar bone regeneration more challenging. In addition, the limited availability of resources in terms of vascularity and underlying tissues is another obstacle to supra-alveolar bone regeneration. Currently, supra-alveolar bone loss is the least predictable periodontal defect type in regenerative periodontal therapy. In addition, supra-alveolar bone loss is much more common than other alveolar bone loss. Despite its prevalence, research on supra-alveolar bone regeneration remains sparse, indicating an unmet need for significant research efforts in this area. This review summarize recent advances, obstacles, and future directions in the field of supra-alveolar bone regeneration. We discuss the biomaterials, bioactive molecules, and cells that have been tested for supra-alveolar bone regeneration, followed by pre-clinical and clinical approaches employed in this field. Additionally, we highlight obstacles and present future directions that will propel supra-alveolar bone research forward.牙周炎是一种非常普遍的疾病，它会破坏牙齿的支持组织，包括牙槽骨。牙周炎导致的牙槽骨缺损大致分为牙槽骨上缺损和牙槽骨内缺损。在牙槽骨内缺损中，缺损与牙根尖方向的牙齿长轴成角或斜向。相比之下，牙槽上骨缺损的缺损方向与牙齿长轴垂直。与牙槽内骨缺损不同，牙槽上骨缺损缺乏邻近空间的支持，这使得牙槽上骨再生更具挑战性。此外，血管和基础组织资源的有限性也是牙槽上骨再生的另一个障碍。目前，牙槽上骨缺失是牙周再生治疗中最难预测的牙周缺损类型。此外，牙槽上骨缺损比其他牙槽骨缺损更为常见。尽管牙槽上骨缺失很普遍，但有关牙槽上骨再生的研究仍然很少，这表明该领域的重大研究工作尚未得到满足。本综述总结了牙槽上骨再生领域的最新进展、障碍和未来方向。我们讨论了用于牙槽骨上部再生的生物材料、生物活性分子和细胞，随后介绍了该领域采用的临床前和临床方法。此外，我们还强调了牙槽上骨研究的障碍，并提出了未来的研究方向，以推动牙槽上骨研究向前发展。Recent and future developments in pultrusion technology with consideration for curved geometries: A reviewSegun Isaac Talabi, Jim Tobin, Benjamin Strom, Ian Brownstein, Vlastimil Kunc, Ahmed Arabi Hassendoi:10.1016/j.compositesb.2024.111678考虑到弯曲几何形状的拉挤技术的近期和未来发展：综述This paper examined the current state and future developments in pultrusion with particular emphasis on its application in curved part manufacturing. The relationship between factors such as resin chemistry, fiber characteristics, and die geometry that influences the properties of pultruded product were highlighted. Moreover, the specific challenges associated with pultruding curved parts such as the complexities in achieving uniformity and structural integrity in such geometries were discussed. The review emphasized mold design, process improvement, adaptive control systems for precise resin impregnation and material selection to address these challenges. Additionally, the paper suggests the integration of real-time monitoring and data analytics as ways to enhance quality control during curved parts pultrusion. These advancements will help to overcome challenges specific to curved pultrusion and make the process more efficient. Other manufacturing techniques such as filament winding, thermoforming, pulforming were mentioned as alternatives to curved parts pultrusion. The review also explores pultruded variable curvature processes, highlighting some notable patents and article related to this subject matter. Production of pultruded variable curvature parts was seen as a key driver that can shape the future of pultrusion. Finally, the paper anticipates future trends, with sustainability, customization, integration of advanced materials, and development of techniques for pultrusion of composites parts.本文探讨了拉挤技术的现状和未来发展，特别强调了拉挤技术在曲面零件制造中的应用。论文强调了影响拉挤产品性能的树脂化学、纤维特性和模具几何形状等因素之间的关系。此外，还讨论了与拉挤曲面零件相关的具体挑战，如在此类几何形状中实现均匀性和结构完整性的复杂性。综述强调了模具设计、工艺改进、用于精确树脂浸渍的自适应控制系统和材料选择，以应对这些挑战。此外，论文还建议整合实时监控和数据分析，以加强曲面部件拉挤过程中的质量控制。这些进步将有助于克服曲面拉挤所特有的挑战，并提高工艺的效率。报告还提到了其他制造技术，如缠绕长丝、热成型、拉挤成型等，作为曲面部件拉挤成型的替代技术。本综述还探讨了拉挤变曲率工艺，重点介绍了与该主题相关的一些著名专利和文章。拉挤可变曲率部件的生产被视为塑造拉挤未来的关键驱动力。最后，本文预测了未来的发展趋势，包括可持续性、定制化、先进材料的集成以及复合材料部件拉挤技术的发展。3D printed carbon fiber reinforced carbon as an energy efficient alternative to graphite for EFAS toolingArin S. Preston, Andrew J. Gorman, Austin C. Matthews, Jorgen F. Rufnerdoi:10.1016/j.compositesb.2024.111679 将 3D 打印碳纤维增强碳作为石墨的节能替代品用于 EFAS 工具As Electric Field Assisted Sintering (EFAS) gains more industrial acceptance and use, it becomes more important to develop more efficient means to implement this technology. To this aim, 3D printed continuous carbon fiber reinforced carbon (CCC) was manufactured and fabricated into tooling for EFAS systems as an alternative to traditional graphite tooling. The impact of fiber orientation on the thermal and electrical properties of the CCC was characterized. Sample material was sintered in Tokai G535 graphite tooling, under common processing conditions and compared with CCC tooling. There was nearly 50 % energy savings compared to graphite while maintaining equivalent sample density and microstructure plus keeping ram temperatures 39 % cooler. This is due to spatial control of generated heat and thermal diffusivity within the molds, by means of fiber orientation anisotropy. Finite element modeling of the tooling design supported the experimental results as well as displays the effect of optimization of this 3D printed CCC material.随着电场辅助烧结技术（EFAS）在工业领域得到越来越多的认可和应用，开发更有效的方法来实施这项技术变得越来越重要。为此，我们制造了三维打印连续碳纤维增强碳（CCC），并将其制作成用于电场辅助烧结系统的工具，以替代传统的石墨工具。纤维取向对 CCC 的热性能和电性能的影响得到了表征。在普通加工条件下，样品材料在东海 G535 石墨模具中烧结，并与 CCC 模具进行比较。与石墨相比，在保持相同样品密度和微观结构的同时，还节省了近 50% 的能源，并使柱塞温度降低了 39%。这是由于通过纤维取向各向异性对模具内产生的热量和热扩散进行了空间控制。模具设计的有限元建模支持了实验结果，并显示了这种三维打印 CCC 材料的优化效果。Post impact repair of in-situ polymerisable thermoplastic based carbon fibre composite and its assessment under compression after impact loadingGursahib Singh Bhatia, Akshay Hejjaji, Anthony J. Comerdoi:10.1016/j.compositesb.2024.111687原位可聚合热塑性碳纤维复合材料的冲击后修复及其在冲击加载后压缩条件下的评估This work investigates the impact response, associated damage, the feasibility of repair and strength recovery of infusible thermoplastic based carbon fibre reinforced composites. Impact behaviour of the laminates is studied using drop tower impact tests at three energy levels i.e. 40 J, 30 J and 20 J resulting in delamination as the primary damage mode at lower energy levels with evidence of fibre breakage at 40 J. Repair is performed by thermally re-consolidating impact damaged specimens under vacuum at a temperature above the glass transition temperature of the matrix. X-ray micro computed tomography (CT) scans and ultrasonic C-Scans reveal significant post repair re-consolidation. Compression testing using compression after impact (CAI) fixture resulted in a retained strength of 78 %, 88 %, and 93 % for impacts at 40 J, 30 J, and 20 J respectively. Post-repair compression strength using CAI tests, recovered 85 % of the pristine strength for 40 J impacts and close to 100 % of pristine strength for both 30 J and 20 J impacts. Thermography during CAI testing revealed a difference in the location of damage initiation under compressive loading for impacted and repaired specimens. The overall results highlight the potential for effective on-site repair and strength recovery using a relatively simple thermal re-consolidation procedure.这项研究调查了基于可注入热塑性塑料的碳纤维增强复合材料的冲击响应、相关损伤、修复可行性和强度恢复情况。通过 40 焦耳、30 焦耳和 20 焦耳三种能量水平的落塔冲击试验研究了层压材料的冲击行为，结果表明，在较低能量水平下，分层是主要的损坏模式，在 40 焦耳时有纤维断裂的迹象。X 射线微型计算机断层扫描（CT）和超声波 C-Scan 显示修复后重新凝固的效果非常明显。使用冲击后压缩（CAI）夹具进行压缩测试，结果显示在 40 J、30 J 和 20 J 的冲击下，强度保持率分别为 78%、88% 和 93%。使用 CAI 测试的修复后压缩强度在 40 J 的冲击下恢复了原始强度的 85%，在 30 J 和 20 J 的冲击下恢复了接近原始强度的 100%。CAI 测试期间进行的热成像显示，冲击试样和修复试样在压缩加载下的损伤起始位置存在差异。总体结果凸显了利用相对简单的热再凝固程序进行有效现场修复和强度恢复的潜力。Mechanical Behavior of MXene-Polymer Layered Nanocomposite Using Computational Finite Element AnalysisAnamika Prasad, Jason Hasse, Timothy Steimle, Dhriti Nepal, Geoffrey J. Frank, Vikas Varshneydoi:10.1016/j.compositesb.2024.111689利用计算有限元分析研究 MXene 聚合物层状纳米复合材料的力学行为The structural integrity of MXene and MXene-based materials is important across applications from sensors to energy storage. While MXene processing has received significant attention, its structural integrity for real-world applications remains challenging due to its flake-like structure. Here the mechanical response of layered MXene-polymer nanocomposites (MPC) with high MXene concentration (>70%) and bioinspired nacre-like brick-and-mortar architecture is investigated to offer insights for MPC design and processing. An automated finite element analysis (FEA) framework is developed to analyze MPC models with randomized geometries and multiple combinations of the parameter space. Specifically, the influence of concentration, aspect ratio (AR), flake thickness, flake distribution, and interfacial strength is investigated. The results reveal property trends such as increasing elastic modulus, strength, and toughness with increasing cohesive strength and concentration for lower AR (=40, 60) but a decreasing trend at higher AR of 75. Local structural features like flake distribution, overlapping MXene lengths, and interconnected polymers in adjacent layers was found a critical determinant of performance. For example, stronger cohesive interaction showed 6X high toughness (291 226 ) compared to weaker case (50 24 ), but the large scatter highlighted the impact of microstructural features. The results are compared and validated with theoretical, computational, and experimental work. The findings provide valuable guidance for optimizing MPC design and their processing. Finally, the automation of the framework allows the design to be extended beyond the current system and chosen material combinations.从传感器到能量存储，MXene 和基于 MXene 的材料的结构完整性在各种应用中都非常重要。虽然 MXene 的加工受到了极大关注，但由于其片状结构，其在实际应用中的结构完整性仍具有挑战性。本文研究了具有高 MXene 浓度（大于 70%）和生物启发的珍珠母状砖瓦结构的层状 MXene 聚合物纳米复合材料（MPC）的机械响应，从而为 MPC 的设计和加工提供启示。研究开发了一个自动有限元分析（FEA）框架，用于分析具有随机几何形状和多种参数空间组合的 MPC 模型。具体而言，研究了浓度、长宽比 (AR)、薄片厚度、薄片分布和界面强度的影响。结果显示了一些特性趋势，如在较低的 AR 值（=40、60）下，随着内聚强度和浓度的增加，弹性模量、强度和韧性也会增加，但在较高的 AR 值（75）下，弹性模量、强度和韧性呈下降趋势。片状分布、MXene 长度重叠以及相邻层中聚合物的相互连接等局部结构特征是决定性能的关键因素。例如，与较弱的情况（50 24）相比，较强的内聚作用显示出 6 倍的高韧性（291 226），但较大的分散性突出了微观结构特征的影响。研究结果与理论、计算和实验工作进行了比较和验证。研究结果为优化 MPC 设计及其加工提供了宝贵的指导。最后，该框架的自动化使设计可以扩展到当前系统和所选材料组合之外。Recyclable azine polyurethane thermosets and carbon fiber reinforced composites with excellent thermostability and mechanical propertiesJinshi Han, Wei Zhang, Mengjie Wei, Ye Zhu, Xiaoya Liu, Xiaojie Lidoi:10.1016/j.compositesb.2024.111693具有优异热稳定性和机械性能的可回收叠氮聚氨酯热固性材料和碳纤维增强复合材料Carbon fiber reinforced composites (CFRCs) have received increasingly concerns and widely used in high-end applications, owing to their outstanding mechanical properties. Most of the polymers used in CFRCs were thermosets. However, a large number of applications brought enormous wastes due to the stable structure of thermosets which is difficult to degrade or recycle. CFRCs based on dynamic covalent polymers (DCPs) were developed to resolve the recycling problem. Polyurethanes were used for fabricating CFRCs applied in energy absorbing materials, vehicle interiors, sporting goods, and constructing materials, owing to excellent toughness, bonding abilities and low VOCs. Although some recyclable PU CFRCs were developed to resolve the recycling of CFs, there remain the problems of excess catalysts, low chemical resistance or thermostability due to the dynamic feature of DCPs. Herein, a series of azine polyurethane thermosets (APUTs) were prepared from hexamethylene diisocyanate (HDI) trimer and dihydroxy azines with different lengths of carbon chains. The resulting APUTs displayed excellent thermal stabilities with all Td,5% exceeding 320 °C, owing to high exchange temperature of azine moieties and high crosslinking density. APUTs-6 showed the highest tensile strength of 36.72 ± 1.18 MPa. APUTs-6 could be easily degraded in 0.1 M acetone/water solution at 50 °C. APUTs-6 showed excellent reprocessing properties and tensile strength could maintain 83.1% of its initial one. The APUTs-6/CFs composites exhibited excellent mechanical properties, chemical resistance and recyclability. CFs could be readily recycled by acid degradation and maintain excellent mechanical properties. The tensile strength of recycled composites could recover 94.36% of the original one after two times of recycling. The recovery ratio of tensile strength of recycled CF filaments was 95.7%. The application of phenyl azine provided a feasible solution for the industrialization of recyclable CFRCs.碳纤维增强复合材料（CFRC）因其出色的机械性能而日益受到关注，并广泛应用于高端领域。碳纤维增强复合材料中使用的大多数聚合物都是热固性材料。然而，由于热固性塑料结构稳定，难以降解或回收，大量应用带来了巨大的浪费。为了解决回收问题，人们开发了基于动态共价聚合物（DCP）的 CFRC。由于聚氨酯具有出色的韧性、粘合能力和低挥发性有机化合物，因此被用于制造 CFRC，应用于吸能材料、汽车内饰、体育用品和建筑材料。虽然一些可回收聚氨酯 CFRC 的开发解决了 CFs 的回收问题，但由于 DCPs 的动态特性，仍存在催化剂过量、耐化学性或热稳定性低等问题。本文利用六亚甲基二异氰酸酯（HDI）三聚体和不同碳链长度的二羟基偶氮制备了一系列偶氮聚氨酯热固性塑料（APUTs）。由于偶氮分子的高交换温度和高交联密度，所制备的 APUT 具有优异的热稳定性，其 Td,5% 均超过 320 ℃。APUTs-6 的拉伸强度最高，达到 36.72 ± 1.18 兆帕。APUTs-6 在 50 ℃ 的 0.1 M 丙酮/水溶液中很容易降解。APUTs-6 显示出优异的再加工性能，拉伸强度可保持在初始值的 83.1%。APUTs-6/CFs 复合材料具有优异的机械性能、耐化学性和可回收性。CFs 可通过酸降解轻松回收，并保持优异的机械性能。经过两次循环后，循环复合材料的拉伸强度可恢复到原来的 94.36%。再生 CF 长丝的拉伸强度恢复率为 95.7%。苯偶氮的应用为可回收 CFRC 的工业化提供了可行的解决方案。Composites Science and TechnologyImproving the interfacial properties of carbon fiber/low melting point PAEK composites by embellishing of bio-based PAEK sizing agentChengan Ma, Fei Yan, Shengtao Dai, Jintang Duan, Yuhui Ao, Gang Li, Gaosong Wang, Qingyu Zhou, Feng Bao, Liu Liudoi:10.1016/j.compscitech.2024.110741 通过添加生物基 PAEK 施胶剂改善碳纤维/低熔点 PAEK 复合材料的界面性能In this study, a bio-based polyarylene ether ketone (bio-PAEK) was synthesized to prepare water-based sizing agents for enhancing the interfacial adhesion between carbon fiber (CF) and matrix. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) results indicated that the bio-PAEK exhibited good thermal properties. To improve the processability and reduce the processing temperature, PAEK with a low melting point (LMPAEK) was also used as the matrix resin. The glass-transition temperature (Tg) of LMPAEK was slightly higher than that of polyether ether ketone (PEEK), but its melting temperature (Tm) was lower 48.5 °C. A strong interface was created after introducing sizing agents onto the CF surface due to good compatibility between fibers and matrix. The interlaminar shear strength (ILSS), interfacial shear strength (IFSS) and flexural strength of CF2/LMPAEK composites increased by 54.7%, 56.0% and 46.6%, respectively, compared with the untreated composites. This study provided a novel approach to prepare water-based bio-PAEK sizing agents for CF composites with a low melting point matrix to be applied in additive manufacturing.本研究合成了一种生物基聚芳醚酮（bio-PAEK），用于制备水基上浆剂，以增强碳纤维（CF）与基体之间的界面粘合力。热重分析（TGA）和差示扫描量热法（DSC）结果表明，生物醚酮具有良好的热性能。为了提高加工性能并降低加工温度，还使用了低熔点 PAEK（LMPAEK）作为基体树脂。LMPAEK 的玻璃化转变温度（Tg）略高于聚醚醚酮（PEEK），但其熔点（Tm）低于 PEEK，为 48.5 °C。由于纤维与基体之间具有良好的相容性，因此在 CF 表面引入施胶剂后会形成牢固的界面。与未处理的复合材料相比，CF2/LMPAEK 复合材料的层间剪切强度（ILSS）、界面剪切强度（IFSS）和弯曲强度分别提高了 54.7%、56.0% 和 46.6%。这项研究提供了一种新方法，用于制备低熔点基体 CF 复合材料的水基生物 PAEK 施胶剂，以应用于增材制造。Stable Energy Storage Performance at High-temperature of PESU-Based Dielectric Composite Regulated by SiO2 and BNNSsYue Zhang, Shaohua Wang, Zheng Gong, Guowei Hao, Changhai Zhang, Yongquan Zhang, Tiandong Zhang, Qi Wang, Qingguo Chidoi:10.1016/j.compscitech.2024.110738 由 SiO2 和 BNNSs 调节的基于 PESU 的电介质复合材料在高温下的稳定储能性能Polymer dielectric capacitors are essential components for energy storage in modern electronic devices. They offer several advantages, including excellent voltage resistance, easy processing, and great energy storage density (U). However, with high thermal and electric fields, the more conductivity losses of polymer dielectric materials can be generated and aggregated, and the discharge energy density (Ue) and charging-discharging efficiency (η) of dielectric capacitor are usually significantly lower than that at room temperature. Here, the state-of-the-art composite is proposed, in which the SiO2 filler with excellent insulation strength is introduced into the middle composite layer, and the composite introduced wide band-gap boron nitride nanosheets (BNNSs) is used as the outer composite layer to inhibit carrier migration and reduce leakage current density of composite. The experimental results illustrate that the Ue of 1BP/1SP/1BP dielectric composite reaches about 9.37 J/cm3, and the η is around 82.0% under the electric field of 540 kV/mm at 80 °C. Significantly, the η of multilayer 1BP/1SP/1BP composite remained > 95.0% after 50,000 cycles, indicating that this multilayer composite has good cycle stability and excellent reliability under a high-temperature. It presents a practical approach to enhance the energy storage performance of dielectric polymer at high-temperature environment.聚合物电介质电容器是现代电子设备储能的重要元件。它们具有多种优点，包括出色的耐压性、易于加工和巨大的能量存储密度（U）。然而，在高热场和电场作用下，聚合物电介质材料会产生和聚集更多的电导损耗，电介质电容器的放电能量密度（Ue）和充放电效率（η）通常明显低于室温下的能量密度和充放电效率。本文提出了一种最先进的复合材料，在中间复合层中引入了绝缘强度极佳的二氧化硅填料，在外层复合层中引入了宽带隙氮化硼纳米片（BNNSs），以抑制载流子迁移并降低复合材料的漏电流密度。实验结果表明，1BP/1SP/1BP 介电复合材料的 Ue 达到约 9.37 J/cm3，η 约为 82.0%。值得注意的是，多层 1BP/1SP/1BP 复合材料的 η 在 50,000 次循环后仍大于 95.0%，表明这种多层复合材料在高温下具有良好的循环稳定性和出色的可靠性。它为提高介电聚合物在高温环境下的储能性能提供了一种实用方法。Multifunctional bamboo-based fiber composites fabricated by assembling 3D network structures of bamboo and spatial distribution of silver nanoparticlesJuan Hu, Jian Lin, Yanglun Yu, Wenji Yu, Chenhuan Lai, Daihui Zhang, Yuxiang Huangdoi:10.1016/j.compscitech.2024.110739 通过组装竹子的三维网络结构和银纳米粒子的空间分布制备多功能竹基纤维复合材料Bamboo-based composites have been commonly used in engineering applications as a renewable carbon recycling material. Despite its prevalent use, bamboo possesses inherent drawbacks, including flammability, moisture absorption, and susceptibility to microbial corrosion, significantly diminishing the service life of the composites as outdoor materials. Hence, a straightforward synthesis strategy was used to prepare multifunctional bamboo-based fiber composites (BFCs). This involved constructing a three-dimensional (3D) network interface within the bamboo via the combination of mechanical and chemical pretreatments, including alkali treatment, in-situ reduction, impregnation, lamination, and hot pressing. The obtained dense structure, together with the successful incorporation of functional AgNPs, enables the composites to exhibit outstanding mechanical properties (328 MPa cm3 g-1 of tensile specific strength). Moreover, the bamboo-based composite shows good flame retardancy (self-extinguishing within 5 seconds after ignition), improved thermal conductivity (0.258 W m-1 K-1), a self-cleaning ability, and commendable antibacterial activity against two common pathogenic bacterial (E. coli and S. aureus). This versatile bamboo-based fiber composite material holds promise for diverse outdoor applications, including roofs, wall panels, outdoor flooring, etc.竹基复合材料作为一种可再生的碳回收材料，已普遍应用于工程领域。尽管竹材的使用非常普遍，但其固有的缺点包括易燃性、吸湿性和易受微生物腐蚀，大大降低了复合材料作为户外材料的使用寿命。因此，我们采用了一种简单的合成策略来制备多功能竹基纤维复合材料（BFCs）。这包括通过机械和化学预处理（包括碱处理、原位还原、浸渍、层压和热压）在竹子内部构建三维（3D）网络接口。所获得的致密结构以及功能性 AgNPs 的成功加入，使复合材料表现出卓越的机械性能（拉伸比强度为 328 MPa cm3 g-1）。此外，竹基复合材料还具有良好的阻燃性（点燃后 5 秒内自熄）、更高的导热性（0.258 W m-1 K-1）、自清洁能力以及对两种常见致病细菌（大肠杆菌和金黄色葡萄球菌）的抗菌活性。这种用途广泛的竹基纤维复合材料有望用于各种户外应用，包括屋顶、墙板、户外地板等。Optimizing the Rheological and Mechanical Properties of Ultra-Highly Filled Wood Fiber/Polyethylene Composites through Binary Alloy Matrix StrategyJunjie Xu, Chuanfu Chen, Yuyu Li, Haiyang Zhou, Xiaolong Hao, Rongxian Ou, Qingwen Wangdoi:10.1016/j.compscitech.2024.110740 通过二元合金基质策略优化超高填充木纤维/聚乙烯复合材料的流变学和力学性能Enhancing the interfacial adhesion and rheological behavior of ultra-highly filled wood-plastic composites (UH-WPCs) presents a considerable challenge. We developed a bespoke binary alloy matrix of high-density polyethylene (HDPE) and maleated polyethylene (MAPE) to fabricate UH-WPCs with 70-90 wt.% filler contents. Fourier-transform infrared spectroscopy and thermogravimetric analysis validated that about 22.3% of MAPE engaged in esterification with wood fibers (WFs) in 80 wt.% loading UH-WPCs, manifesting in noteworthy plasticization as evidenced by WFs' sheet-like structures. Rheological assessments illustrated that higher MAPE proportions reduced the viscosity of both the specialized alloy and UH-WPC melts significantly. By fine-tuning the MAPE to HDPE ratio to 16:2, we achieved marked enhancements in UH-WPCs' mechanical properties and dimensional stability: tensile strength and flexural strength increased by up to 141.7% and 151.0%, respectively, while creep strain and equilibrium water absorption decreased by as much as 27.3% and 36.7%. This research lays a robust scientific foundation for the efficient processing and enhancement of UH-WPCs, highlighting its potential for substantial improvements in mechanical performance, stability, and processability.增强超高填充木塑复合材料（UH-WPCs）的界面粘附性和流变特性是一项巨大的挑战。我们开发了一种定制的高密度聚乙烯（HDPE）和马来酸化聚乙烯（MAPE）二元合金基体，用于制造填充物含量为 70-90 wt.%的超高填充木塑复合材料。傅立叶变换红外光谱和热重分析证实，在 80 wt.% 填料含量的 UH-WPCs 中，约 22.3% 的马来酸聚乙烯与木纤维（WFs）发生了酯化反应，表现为显著的塑化，木纤维的片状结构就是证明。流变学评估表明，MAPE 比例越高，专用合金和超高分子量聚碳酸酯熔体的粘度就越低。通过将 MAPE 与 HDPE 的比例微调至 16:2，我们明显提高了超高分子量聚碳酸酯的机械性能和尺寸稳定性：拉伸强度和弯曲强度分别提高了 141.7% 和 151.0%，而蠕变应变和平衡吸水率则分别降低了 27.3% 和 36.7%。这项研究为超高分子量聚碳酸酯的高效加工和增强奠定了坚实的科学基础，凸显了其在机械性能、稳定性和可加工性方面大幅提高的潜力。来源：复合材料力学仿真Composites FEM
