今日更新:Composites Part A: Applied Science and Manufacturing 1 篇,Composites Part B: Engineering 9 篇,Composites Science and Technology 1 篇
Impregnation process of large-tow carbon-fiber woven fabric/polyamide 6 composites using solvent method
Osuke Ishida, Shiho Oda, Kiyoshi Uzawa
doi:10.1016/j.compositesa.2024.108068
采用溶剂法的大纤度碳纤维编织物/聚酰胺 6 复合材料浸渍工艺
Large-tow carbon fibers (CF) are suitable for low-cost industrial applications. However, it is challenging to impregnate large fiber bundles with thermoplastics owing to their high melt viscosity. In this study, polyamide 6 (PA 6) is dissolved in a mixture of calcium chloride and methanol to decrease its viscosity, and a large-tow CF fabric is immersed in the solution. Subsequently, the solvent is removed with water and the fabric is dried. Scanning electron microscopy observations indicate that many PA6 particles are present inside the fiber bundles owing to solution impregnation. Thereafter, compression molding is conducted using a stack of additional PA6 films. The fabricated composites exhibit much better impregnation quality than those fabricated without solution impregnation. The quality of impregnation is also impacted by the concentration of the solution because it affects the amount of PA6 in the CF tow and the remaining calcium chloride.
大束碳纤维(CF)适用于低成本的工业应用。然而,由于大纤维束的熔体粘度较高,用热塑性塑料浸渍大纤维束具有挑战性。在这项研究中,将聚酰胺 6(PA 6)溶解在氯化钙和甲醇的混合物中以降低其粘度,然后将大纤度碳纤维织物浸入溶液中。随后,用水除去溶剂并将织物烘干。扫描电子显微镜观察表明,由于溶液浸渍,纤维束内存在许多 PA6 颗粒。随后,使用额外的 PA6 薄膜堆叠进行压缩成型。与未进行溶液浸渍的复合材料相比,制成的复合材料的浸渍质量要好得多。浸渍质量还受到溶液浓度的影响,因为溶液浓度会影响 CF 纤维束中 PA6 的含量和剩余的氯化钙。
Simultaneous toughening and strengthening of CF/EP composites through bi-component thermoplastics with hybrid phases between composite layers
Yi Xue, Zhaoyang Li, Jiamei Luo, Xueqin Yang, Zehao Yang, Yanhua Shi, Yong Liu, Yu Ma, Hui Zhang, Jianyong Yu
doi:10.1016/j.compositesb.2024.111286
通过在复合材料层之间添加混合相的双组分热塑性塑料,同时增韧和增强 CF/EP 复合材料
In this work, bi-component polyaryletherketone-cardo/polyethersulfone (PEK-C/PES) films with different areal densities were designed and fabricated by phase inversion approach, applied as interleaves to simultaneously toughen and strengthen the carbon fiber/epoxy resin (CF/EP) composites prepared by vacuum-assisted resin infusion process (VARI). Optical microscopy observations manifested that the PEK-C/PES films could maintain stability at the infusion temperature of epoxy resin. Nonetheless, PEK-C/PES films could dissolve into the epoxy resin at heating and later stages of curing, by which the distribution of PEK-C and PES between the layers of CF/EP composites could be effectively controlled. Interestingly, both Mode I and Mode II fracture toughness of the CF/EP composites interleaved with PEK-C/PES films of optimal areal density (22.0 gsm) increased by 135.3% and 51.6%, respectively, compared with the untoughened composites. Furthermore, the PEK-C/PES films resulted in a 62.4% improvement in the compression-after-impact (CAI) strength CF/EP composites. Additionally, observation of the fracture surfaces of Mode I and Mode II specimens by scanning electron microscopy revealed that PEK-C had good compatibility with epoxy resin and formed a “scale-like” phase structure, which significantly improved the toughness of the CF/EP composites. While the “sea island-like” microspheres developed by PES between the CF/EP composite layers could cause the deflection and termination of cracks, thus enlarging the surface area of cracks. In addition, the tensile, flexural, and interlaminar shear properties of CF/EP composites were moderately enhanced, attributed to the incorporation of PEK-C/PES films. This cost-effective approach reconciles efficiently the conflict of the interlaminar toughness and in-plane mechanical properties of composites for fabricating of high toughness CF/EP composites.
在这项工作中,采用相反转方法设计并制备了不同等密度的双组分聚芳醚酮-卡多/聚醚砜(PEK-C/PES)薄膜,并将其用作交织层,以同时韧化和增强通过真空辅助树脂灌注工艺(VARI)制备的碳纤维/环氧树脂(CF/EP)复合材料。光学显微镜观察表明,PEK-C/PES 薄膜在环氧树脂灌注温度下仍能保持稳定。然而,PEK-C/PES 薄膜在加热和后期固化阶段会溶解到环氧树脂中,从而有效控制了 PEK-C 和 PES 在 CF/EP 复合材料层间的分布。有趣的是,与未增韧的复合材料相比,交错有最佳面积密度(22.0 克/平方米)PEK-C/PES 薄膜的 CF/EP 复合材料的模式 I 和模式 II 断裂韧性分别提高了 135.3% 和 51.6%。此外,PEK-C/PES 薄膜还使 CF/EP 复合材料的冲击后压缩(CAI)强度提高了 62.4%。此外,通过扫描电子显微镜观察模式 I 和模式 II 试样的断裂表面发现,PEK-C 与环氧树脂具有良好的相容性,并形成了 "鳞片状 "相结构,从而显著提高了 CF/EP 复合材料的韧性。而 PES 在 CF/EP 复合材料层之间形成的 "海岛状 "微球可导致裂纹的偏转和终止,从而扩大了裂纹的表面积。此外,由于加入了 PEK-C/PES 薄膜,CF/EP 复合材料的拉伸、弯曲和层间剪切性能都得到了适度提高。这种经济有效的方法有效地解决了复合材料层间韧性和面内机械性能之间的矛盾,从而制造出了高韧性 CF/EP 复合材料。
Superior shear strength subject to the regulation of plastic toughness in K4169 alloy/TiAl intermetallic joints vacuum brazed with gradient composite amorphous filler metals
Liangliang Zhang, Peng Li, Shuai Li, Fuheng Nie, Baosheng Wu, Chao Li, Jiachen Li, Zhenyang Zhang, Xin Jiang, Bomin Zhao, Honggang Dong
doi:10.1016/j.compositesb.2024.111288
使用梯度复合非晶填充金属真空钎焊的 K4169 合金/TiAl 金属间化合物接头的超强剪切强度受塑性韧性的影响
The concept of gradient composite amorphous filler metal (GAFM) was utilized to solve the scientific problem of low strength caused by excessive Ti-containing brittle-hard intermetallic compounds (IMCs) generated in Ni/TiAl brazed joints through interfacial hysteresis reaction. Based on the cluster-plus-glue-atom model, the GAFMs (Zr25Ti21.25Ni25Cu18.75/Zr31.25-XVXCu50Ni18.75) were designed for vacuum brazing of K4169 alloy with TiAl intermetallic. And the shear strength of the joint brazed with (Ti21.25Zr25Ni25Cu18.75/Zr25V6.25Cu50Ni18.75) GAFM reached 344 MPa. The relation between grain boundary, solution, dislocation and strength was established. The cracks initiated from the (Ti,Zr)(Ni,Cu)+(Cr,Fe,Ni) brittle-hard phase and the plastic-tough phase (Zr,Ti)(Ni,Cu) interface in Zone II with (Ti21.25Zr25Ni25Cu18.75/Zr31.25-XVXCu50Ni18.75) GAFMs at 1040 °C/10 min, and then extended to the (Ti,Zr)(Al,Ni,Cu)3[010]/(Ti,Zr)(Ni,Cu,Al)3[0-10] non-coherent interface. To regulate the distribution of the plastic-tough phase in Zone II, raising brazing temperature could promote the dissolution of Zone I into Zone II. The addition of V to the GAFMs, εG and εα mismatches increased and prompted the Niss[00-1]+TiAl[010] phase, (Cr,Fe,Ni)ss[00-1] phase with a-value lattice distortion of 21.38%, (Ni,Cr,Fe) and ZrNi3[0-2-1] grains refinement in Zone II, where KIC*/KIC>1, the brazed joint strengthening effect was enhanced. The columnar grains were transformed into grains with reticulated cladding characteristics. The percentage of substructured grains increased from 46.6% to 56.3%, and the percentage of HAGBs rose to 84.7%, which inhibited dislocation migration. Therefore, the ZrNi3 plastic-tough phase, prohibited the expansion of the major crack generated from the (Cr,Fe,Ni) brittle-hard phase. The major crack extended to the Ti(Ni,Cu,Al)3 [1–10]/Ti(Al,Cu,Ni)2[0-10] semi-coherent interface and then to the TiAl substrate, resulting in a zigzag crack expansion.
利用梯度复合非晶填充金属(GAFM)的概念,解决了镍/钛铝钎焊接头中因界面滞后反应产生过多含钛脆硬金属间化合物(IMC)而导致强度低的科学难题。根据簇加胶原子模型,设计了 GAFMs(Zr25Ti21.25Ni25Cu18.75/Zr31.25-XVXCu50Ni18.75),用于含 TiAl 金属间化合物的 K4169 合金的真空钎焊。用(Ti21.25Zr25Ni25Cu18.75/Zr25V6.25Cu50Ni18.75)GAFM 钎焊的接头剪切强度达到 344 兆帕。建立了晶界、溶解、位错和强度之间的关系。裂纹从 II 区的(Ti,Zr)(Ni,Cu)+(Cr,Fe,Ni)脆硬相和(Ti21.Zr)(Ni,Cu)塑韧相界面开始。 25Zr25Ni25Cu18.75/Zr31.25-XVXCu50Ni18.75)GAFMs在1040 ℃/10分钟的条件下,然后扩展到(Ti,Zr)(Al,Ni,Cu)3[010]/(Ti,Zr)(Ni,Cu,Al)3[0-10]非相干界面。为了调节塑韧相在 II 区的分布,提高钎焊温度可促进 I 区溶解到 II 区。在 GAFMs 中加入 V,εG 和 εα 失配增加,促使 Niss[00-1]+TiAl[010] 相、(Cr,Fe,Ni)ss[00-1]相(a 值晶格畸变为 21.38%)、(Ni,Cr,Fe)和 ZrNi3[0-2-1] 晶粒在 II 区细化,其中 KIC*/KIC>1 时,钎焊接头强化效果增强。柱状晶粒转变为具有网状包覆特征的晶粒。亚结构晶粒的比例从 46.6% 增加到 56.3%,HAGB 的比例上升到 84.7%,从而抑制了位错迁移。因此,ZrNi3 塑性韧相阻止了(Cr,Fe,Ni)脆硬相产生的主要裂纹的扩展。主要裂纹扩展到 Ti(Ni,Cu,Al)3 [1-10]/Ti(Al,Cu,Ni)2[0-10] 半相干界面,然后扩展到 TiAl 基体,形成人字形裂纹扩展。
The effect of laser assisted tape placement processing conditions on microstructural evolution, residual stress and interlaminar shear strength of carbon fibre/PEEK laminates
Hong Ma, Aswani Kumar Bandaru, Paul M. Weaver
doi:10.1016/j.compositesb.2024.111293
激光辅助贴带加工条件对碳纤维/PEEK 层压板微结构演变、残余应力和层间剪切强度的影响
In the present study, both experiments and thermo-mechanical coupled simulations were conducted to characterise the diverse crystallisation behaviours and the processing parameter-microstructure-mechanical property relationships occurring in laser-assisted tape placement (LATP) manufacturing of carbon fibre (CF)/Polyetheretherketone (PEEK) laminates. Specifically, at various processing temperatures (350 °C or 400), increasing the compaction pressure from 2 to 4 bar causes distinct defect distribution behaviours. However, variations in processing parameters show minimal effect on the morphology and size of crystallised spherulites, which were consistently around 2–3 μm in size, resulting in a final crystallinity of manufactured laminates within 30%–35%. It was found that the cold crystallisation processes occurring in PEEK during LATP play an important role in determining the final degree of crystallinity. Experimental measurements and simulations indicate that changes in processing parameters have a negligible effect on residual stress levels, especially regarding interlaminar residual stresses. A processing temperature of 400 °C was found to generate a diffuse, yet coherent, interphase spanning the fibre/matrix interface with a thickness approximately 70 nm. In contrast, at a processing temperature of 350 °C, a distinct, incoherent interface was confirmed between fibre and matrix. The formation of the interphase, coupled with fewer defects, leading to a relatively high interlaminar shear strength (78 MPa) of manufactured laminates under appropriate processing conditions. Therefore, it is suggested that regulating the degree of cold crystallisation in polymer matrices while ensuring a strong fibre/matrix interfacial bond by the optimisation of processing temperature, will enable the tailoring of microstructure and design of composites to meet specific strength property requirements.
本研究通过实验和热机械耦合模拟来描述碳纤维(CF)/聚醚醚酮(PEEK)层压板在激光辅助贴带(LATP)制造过程中发生的各种结晶行为以及加工参数-微结构-机械性能之间的关系。具体来说,在不同的加工温度(350 °C 或 400)下,将压实压力从 2 巴增加到 4 巴会导致不同的缺陷分布行为。然而,加工参数的变化对结晶球粒的形态和大小影响甚微,结晶球粒的大小始终保持在 2-3 μm 左右,因此制造出的层压板的最终结晶度在 30%-35% 之间。研究发现,PEEK 在 LATP 过程中发生的冷结晶过程在决定最终结晶度方面发挥了重要作用。实验测量和模拟表明,加工参数的变化对残余应力水平的影响微乎其微,尤其是层间残余应力。研究发现,加工温度为 400 ℃ 时,纤维/基体界面上会产生一个弥散但连贯的层间相,厚度约为 70 nm。相比之下,在加工温度为 350 ℃ 时,纤维和基体之间出现了明显的不连贯界面。夹层的形成加上较少的缺陷,使得在适当的加工条件下制造的层压板具有相对较高的层间剪切强度(78 兆帕)。因此,建议通过优化加工温度来调节聚合物基体的冷结晶程度,同时确保纤维/基体界面的牢固结合,这样就能定制复合材料的微观结构和设计,以满足特定的强度性能要求。
Composite materials combined with stem cells promote kidney repair and regeneration
Hao Tian, Liulin Wu, Haoxiang Qin, Xiaochen Li, Xingli Zhao, Wenyan Zhao, Fangchao Xue, Shanlan Zhao, Lang Li, Wen Zeng
doi:10.1016/j.compositesb.2024.111278
复合材料与干细胞相结合促进肾脏修复和再生
Kidney disease is a worldwide public health problem, seriously threatening the quality of life of human beings, mainly including acute kidney injury (AKI), chronic kidney disease (CKD), and end-stage renal disease (ESRD), with a high mortality rate. Current effective treatments include dialysis and kidney transplants, but shortages of donor organs, immune rejection, and other problems have not been effectively addressed. In recent years, stem cells have been extensively studied, due to the proliferation and multi-directional differentiation properties, stem cells have shown great potential for applications in the field of tissue regeneration, which may be an effective means for kidney repair and regeneration. At the same time, the rapid development of composite materials show excellent performance in hemostasis, anti-inflammatory, organoids and kidney scaffolds construction, which is expected to further guide stem cells in promoting kidney repair and regeneration. In this review, we discuss the latest research progress in kidney repair and regeneration from the perspectives of stem cell and extracellular vesicle (EVs) regulation, composite material regulation, composite material combined with stem cells used in tissue engineering kidneys and organoids culture. Besides, we further analyze and summarize the mechanisms as well as pathways. In addition, we raise key issues that currently constrain composites as well as stem cell therapy for kidney disease. Finally, we further discuss the possible future development direction in the field of kidney regeneration.
肾脏病是世界性的公共卫生问题,严重威胁人类的生活质量,主要包括急性肾损伤(AKI)、慢性肾脏病(CKD)和终末期肾脏病(ESRD),死亡率极高。目前有效的治疗方法包括透析和肾移植,但供体器官短缺、免疫排斥等问题尚未得到有效解决。近年来,干细胞被广泛研究,由于干细胞具有增殖和多向分化特性,在组织再生领域显示出巨大的应用潜力,可能成为肾脏修复和再生的有效手段。同时,复合材料的快速发展在止血、抗炎、器官组织和肾脏支架构建等方面表现出优异的性能,有望进一步引导干细胞促进肾脏修复与再生。在这篇综述中,我们从干细胞和细胞外囊泡(EVs)调控、复合材料调控、复合材料与干细胞结合用于组织工程肾脏和类器官培养等方面探讨了肾脏修复与再生的最新研究进展。此外,我们还进一步分析和总结了其机制和途径。此外,我们还提出了目前制约复合材料以及干细胞治疗肾脏疾病的关键问题。最后,我们进一步讨论了肾脏再生领域未来可能的发展方向。
Highly adhesive self-reinforce hydrogel for the amelioration of intervertebral disc degeneration: Eliminating reactive oxygen species and regulating extracellular matrix
Yu-cai Li, Zhen-yuan Wei, Bin Chai, Zhen Pan, Shun-zhe Zhang, Hua Li, Jie-lin Wang, Xiao-jian Ye
doi:10.1016/j.compositesb.2024.111280
用于改善椎间盘退行性病变的高粘合性自增强水凝胶:消除活性氧并调节细胞外基质
Intervertebral disc degeneration (IVDD) plays a pivotal etiological role in low back pain, which is a global cause of disability. Although the underlying pathological processes and mechanisms of IVDD are complex, oxidative stress and extracellular matrix degradation are recognized as crucial determinants of degeneration. The delicate equilibrium between reactive oxygen species and antioxidants holds profound significance in maintaining normal cellular functions, while the extracellular matrix maintains intervertebral disc stability. This study developed a bioadhesive with mechanical properties similar to those of the nucleus pulposus, an injectable hydrogel. Unlike other antioxidative drug carrier materials, this hydrogel achieved oxidative stress removal through the material and loaded transforming growth factor-beta 3 gradually released to regulate the extracellular matrix. Cellular experiments demonstrated the ability of the hydrogel to scavenge oxygen radicals, stimulate nucleus pulposus cell migration, and regulate collagen secretion. Moreover, radiographic and histological analyses in a needle-induced rat-tail IVDD model confirmed the potential of the hydrogel to restore disc height, maintain disc hydration, preserve disc tissue structure, and promote collagen secretion. These findings have promising implications for the potential efficacy of hydrogels in ameliorating IVDD.
椎间盘退变(IVDD)在腰背痛中起着举足轻重的病因作用,而腰背痛是全球致残的原因之一。虽然椎间盘退变的基本病理过程和机制十分复杂,但氧化应激和细胞外基质降解被认为是退变的关键决定因素。活性氧和抗氧化剂之间的微妙平衡在维持细胞正常功能方面具有深远意义,而细胞外基质则维持着椎间盘的稳定性。本研究开发了一种生物粘合剂,其机械特性与髓核相似,是一种可注射的水凝胶。与其他抗氧化载药材料不同的是,这种水凝胶通过材料实现了氧化应激的清除,并负载了转化生长因子-β3,逐渐释放出来调节细胞外基质。细胞实验证明,水凝胶具有清除氧自由基、刺 激髓核细胞迁移和调节胶原蛋白分泌的能力。此外,在针 刺诱导的大鼠尾部 IVDD 模型中进行的放射学和组织学分析证实,水凝胶具有恢复椎间盘高度、保持椎间盘水合作用、保护椎间盘组织结构和促进胶原蛋白分泌的潜力。这些发现对水凝胶改善 IVDD 的潜在疗效具有良好的影响。
Biomaterials for diabetic bone repair: Influencing mechanisms, multi-aspect progress and future prospects
Bingbing Wang, Yong Huang, Qiang Cai, Zhipo Du, Xiaoming Li
doi:10.1016/j.compositesb.2024.111282
用于糖尿病骨修复的生物材料:影响机制、多方面进展与未来展望
Disturbed glucose metabolism in diabetes mellitus (DM) patients affects bone metabolism and its microenvironment, which significantly impaired bone regeneration, making bone defect repair in DM patients a big challenge. Although autologous and allogeneic bone grafts are common therapeutic approaches, they do not achieve the desired therapeutic outcome, especially when targeting the complex pathologic microenvironment at the lesion site in DM patients. Therefore, various biomaterials have been developed to facilitate DM bone repair. With advances in bone tissue engineering, the focus of the study has transitioned from biologically inert to bioactive biomaterials. However, due to the lack of a comprehensive understanding of the pathologic microenvironment of diabetic bone defects, many biomaterials have not achieved satisfactory therapeutic results. Here, the mechanisms by which the pathological microenvironment affects bone regeneration are dissected. Then, recent advances in biomaterial therapeutic strategies based on these pathological microenvironments are comprehensively reviewed from seven aspects. Finally, current limitations that still need to be addressed are discussed, and feasible strategies for improvement and perspectives are presented. This review will certainly spark new ideas to develop more high-performance versatile biomaterials to improve the repair of bone defects under pathological conditions.
糖尿病(DM)患者的糖代谢紊乱会影响骨代谢及其微环境,从而严重影响骨再生,使DM患者的骨缺损修复面临巨大挑战。虽然自体和异体骨移植是常见的治疗方法,但它们并不能达到预期的治疗效果,尤其是在针对 DM 患者病变部位复杂的病理微环境时。因此,人们开发了各种生物材料来促进 DM 骨修复。随着骨组织工程学的发展,研究重点已从生物惰性材料过渡到生物活性生物材料。然而,由于缺乏对糖尿病骨缺损病理微环境的全面了解,许多生物材料的治疗效果并不理想。本文将剖析病理微环境对骨再生的影响机制。然后,从七个方面全面回顾了基于这些病理微环境的生物材料治疗策略的最新进展。最后,讨论了目前仍需解决的局限性问题,并提出了可行的改进策略和展望。这篇综述必将引发新的思路,从而开发出更多高性能的多功能生物材料,改善病理条件下的骨缺损修复。
Bio-inspired design and unusual mechanical properties of 3D horseshoe-shaped soft network metamaterials
Jingxuan Zhou, Jiahui Chang, Xiaoning Song, Zheng-Yang Li, Li-Yuan Zhang, Hongbo Li, Jie Zhang, Dongjia Yan, Chuanzeng Zhang
doi:10.1016/j.compositesb.2024.111284
三维马蹄形软网络超材料的生物启发设计和非同寻常的机械特性
Biological tissues possess high stretchability and nonlinear mechanical response owing to their wavy and crimped microstructure. The metamaterials exhibit unusual physical and mechanical properties, dominated by the configuration of artificial periodic microstructures. However, the development of bio-inspired designs and three-dimensional (3D) soft metamaterials that can achieve a variety of unusual mechanical properties remains challenging. Here, we reported a class of 3D horseshoe-shaped soft network metamaterials with tunable nonlinear mechanical response and tension-torsion coupling effect. Based on the 3D horseshoe-shaped microstructure and octahedron lattice arrangement, the designed 3D soft network metamaterials can exhibit J-shaped stress-strain curve and large angle of torsion with large levels of deformation under tension. The mechanical properties of the 3D soft network metamaterials in different characteristic directions are investigated, where a negative Poisson's ratio appears. Furthermore, the extended design that the 3D horseshoe-shaped microstructures are replaced by the semi-elliptic and quarter-arc-straight joint microstructures can tune a wide range of desired J-shaped stress-strain curves. Thus, the multi-unusual mechanical properties provide potential uses in multi-functional metamaterials and flexible bio-integrated devices.
生物组织因其波浪状和卷曲的微结构而具有高伸展性和非线性机械响应。超材料表现出不同寻常的物理和机械特性,这主要是由人工周期性微结构的配置所决定的。然而,开发生物启发设计和三维(3D)软超材料以实现各种不同寻常的机械特性仍具有挑战性。在此,我们报告了一类具有可调非线性机械响应和张扭耦合效应的三维马蹄形软网络超材料。基于三维马蹄形微结构和八面体晶格排列,所设计的三维软网络超材料在张力作用下可表现出 J 型应力应变曲线和大扭转角以及大变形量。研究了三维软网络超材料在不同特征方向上的力学性能,其中出现了负泊松比。此外,将三维马蹄形微结构替换为半椭圆形和四分之一弧形直缝微结构的扩展设计,可以调谐出各种所需的 J 型应力应变曲线。因此,这种多重异常机械特性为多功能超材料和柔性生物集成装置提供了潜在用途。
A partial dissolution-regeneration strategy for preparing water-resistant composite film of cellulose I and cellulose II with high light transmittance and adjustable haze
Lijiaqi Zhang, Yong Huang, Min Wu
doi:10.1016/j.compositesb.2024.111285
制备具有高透光率和可调雾度的纤维素 I 和纤维素 II 防水复合膜的部分溶解-再生策略
Due to the excellent properties of nanocellulose film such as biodegradability and renewability, researchers have conducted in-depth research on it in recent years. However, rich hydroxyl groups on the surface of nanocellulose make it hydrophilic, and small gaps between the fibrils have significant capillary effect, which cause the strength of nanocellulose film drastically deteriorates when exposed to water, severely restricting its scope of use. In this study, the nanocellulose prepared by ball milling was used to prepare nanocellulose film, and the surface of the film was partially dissolved by ZnCl2. The dense regenerated cellulose (Cellulose Ⅱ) with Zn2+ on the surface made the film hydrophobic, effectively reduced the water absorption rate of the film, and also maintained the internal structure of the nanocellulose. Through this strategy, the nanocellulose film with high dry strength (151–176 MPa), wet strength (27.6–31.7 MPa), high light transmittance (80–91%), and adjustable haze (50–90%) was obtained. This study provides a facile and environmentally friendly strategy to improve the wet strength of nanocellulose film, which broadens its application prospect in packaging materials and electronic devices.
由于纳米纤维素薄膜具有生物降解性和可再生性等优良特性,近年来研究人员对其进行了深入研究。然而,纳米纤维素表面丰富的羟基使其具有亲水性,纤维间的微小空隙具有显著的毛细管效应,这导致纳米纤维素薄膜遇水后强度急剧下降,严重限制了其使用范围。本研究采用球磨法制备纳米纤维素,并用 ZnCl2 部分溶解薄膜表面。表面含有 Zn2+ 的致密再生纤维素(纤维素Ⅱ)使薄膜具有疏水性,有效降低了薄膜的吸水率,同时也保持了纳米纤维素的内部结构。通过这种策略,获得了具有高干强度(151-176 MPa)、湿强度(27.6-31.7 MPa)、高透光率(80-91%)和可调雾度(50-90%)的纳米纤维素薄膜。该研究为提高纳米纤维素薄膜的湿强度提供了一种简便、环保的策略,拓宽了其在包装材料和电子设备中的应用前景。
Compatibilization of ultra-high molecular weight polyethylene (UHMWPE) fibers and their composites for superior mechanical performance: A concise review
Daksh Shelly, Seul-Yi Lee, Soo-Jin Park
doi:10.1016/j.compositesb.2024.111294
超高分子量聚乙烯 (UHMWPE) 纤维及其复合材料的相容,以获得优异的机械性能:简明综述
In the industrial sector, ultra-high molecular weight polyethylene (UHMWPE) fibers are often recognized as superlative reinforcement owing to their unmatchable characteristics like impressive toughness, exceptional weight-to-strength ratio, low density, excellent wear, and chemical resistance. The remarkable features of UHMWPE fiber/polymer composites have gained substantial attention, rendering them ideal for advanced engineering materials. Despite this, advancements in developing high-performance UHMWPE fiber polymer composites have been constrained by the fiber's smooth and chemically inert surface, resulting in a weak interface between UHMWPE and the polymer matrix. Numerous techniques have emerged to enhance the surface of UHMWPE fibers, aiming to bolster the fiber-polymer matrix interface. These modifications amplify surface chemical activity and roughness, thus achieving robust mechanical interlocking and chemical bonding. This review paper aims to elucidate how the physical and chemical surface modifications of UHMWPE fibers fortify the interface with polymer matrices. Researchers can leverage the presented techniques to design advanced composites with improved performance and durability. This article provides a concise overview of current developments in various surface modification techniques for UHMWPE fibers and their role as polymer reinforcements. Last, ongoing challenges and potential research directions in UHMWPE reinforced FRPCs are also discussed.
在工业领域,超高分子量聚乙烯(UHMWPE)纤维因其无与伦比的特性,如令人印象深刻的韧性、优异的重量-强度比、低密度、优异的耐磨性和耐化学性,通常被视为超级增强材料。超高分子量聚乙烯纤维/聚合物复合材料的显著特性已引起广泛关注,使其成为先进工程材料的理想选择。尽管如此,开发高性能超高分子量聚乙烯纤维聚合物复合材料的进展一直受到纤维光滑和化学惰性表面的限制,导致超高分子量聚乙烯与聚合物基体之间的界面薄弱。为了增强纤维与聚合物基体之间的界面,出现了许多增强超高分子量聚乙烯纤维表面的技术。这些改性技术可提高表面化学活性和粗糙度,从而实现牢固的机械互锁和化学键合。本综述论文旨在阐明超高分子量聚乙烯纤维的物理和化学表面改性如何强化与聚合物基质的界面。研究人员可利用所介绍的技术设计出性能更佳、更耐用的先进复合材料。本文简要概述了超高分子量聚乙烯纤维各种表面改性技术的当前发展及其作为聚合物增强材料的作用。最后,还讨论了超高分子量聚乙烯增强 FRPC 所面临的挑战和潜在的研究方向。
High energy dissipation and self-healing auxetic foam by integrating shear thickening gel
Kang Zhang, Qiang Gao, Jingchao Jiang, Meishan Chan, Xiaoya Zhai, Liuchao Jin, Jiangfan Zhang, Jifan Li, Wei-Hsin Liao
doi:10.1016/j.compscitech.2024.110475
通过整合剪切增稠凝胶实现高能量耗散和自修复辅助泡沫
Herein, we report a novel hybrid auxetic foam (HAF) with high energy dissipation and self-healing properties prepared by integrating shear thickening gel (STG) with auxetic polyurethane foam (APF). Due to the synergetic action of shear thickening property of STG and the negative Poisson's ratio of APF, HAF shows better impact protection performance than APF and PU foam. The quasi-static compression test shows the energy dissipation ability of HAF is around 4 times that of APF. The dynamic impact test demonstrates that the force reduction of HAF increases by as high as 64 %, compared to APF. Notably, the force reduction improvement of the HAF is much higher than other hybrid auxetic materials. It is also found that the peak force of HAF is reduced as the amount of STG increases. Additionally, the peak force difference between HAF and APF becomes larger when they are subjected to higher impact energies, due to the rate-dependent effect of STG inside the foam. The Poisson's ratio results for HAF with different STG content under low and high compression strain rates reveal that the dimension of auxetic cell structures and STG content are required to be carefully designed to maximize the synergistic effect of auxetic property and shear thickening property. Besides, HAF demonstrates self-healing ability, allowing it to repair damage sustained during use and can be assembled like Lego blocks to make structures with any irregular shapes. Our work provides ideas for the development of advanced auxetic materials, with the potential to revolutionize a wide range of applications.
在此,我们报告了一种新型混合助剂泡沫(HAF),该泡沫由剪切增稠凝胶(STG)和助剂聚氨酯泡沫(APF)混合制备而成,具有高能量耗散和自愈性能。由于 STG 的剪切增稠特性和 APF 的负泊松比的协同作用,HAF 比 APF 和聚氨酯泡沫具有更好的冲击防护性能。准静态压缩试验表明,HAF 的消能能力约为 APF 的 4 倍。动态冲击测试表明,与 APF 相比,HAF 的力减小率提高了 64%。值得注意的是,HAF 的减力效果远高于其他混合辅助材料。研究还发现,随着 STG 用量的增加,HAF 的峰值力也会减小。此外,由于泡沫内部 STG 的速率效应,当 HAF 和 APF 承受更高的冲击能量时,它们之间的峰值力差异会变得更大。不同 STG 含量的 HAF 在低压缩应变率和高压缩应变率条件下的泊松比结果表明,需要精心设计辅助细胞结构的尺寸和 STG 含量,以最大限度地发挥辅助特性和剪切增厚特性的协同效应。此外,HAF 还具有自我修复能力,可以修复使用过程中受到的损伤,并且可以像乐高积木一样组装成任何不规则形状的结构。我们的工作为开发先进的辅助材料提供了思路,有望为广泛的应用领域带来变革。