首页/文章/ 详情

【新文速递】2024年3月2日固体力学SCI期刊最新文章

2天前浏览195

 

今日更新:Journal of the Mechanics and Physics of Solids 2 篇,Mechanics of Materials 1 篇,Thin-Walled Structures 2 篇

Journal of the Mechanics and Physics of Solids

A Theoretical Model of Enhanced Adhesion of Bioinspired Micropillar Arrayed Surfaces

Yonggui Cheng, Zhilong Peng, Shaohua Chen

doi:10.1016/j.jmps.2024.105592

生物启发微柱阵列表面附着力增强的理论模型

To achieve better adhesion, micropillar arrayed surfaces inspired by the gecko adhesion system have gained significant attention. However, debate continues on whether micropillar arrayed surfaces actually enhance interfacial adhesion compared to smooth surfaces. To clearly understand the factors influencing the adhesion force of micropillar arrayed surfaces and provide a criterion for achieving enhanced adhesion of such the surfaces, a theoretical model of a micropillar arrayed surface containing an elastic backing layer is established. Under a vertically uniform displacement load, the micropillars will detach from the rigid substrate. The adhesion behavior of each micropillar and the variation pattern of the entire adhesion force influenced by the geometry of the micropillars, materials of the micropillars and backing layer during the detaching process are analyzed. A load sharing efficiency is defined, and is found to increase with an increase in the micropillar aspect ratio, Young's modulus ratio of the backing layer to the micropillars, and separation distance between neighboring micropillars, but decrease with an increase in sample size. The entire adhesion force of a micropillar arrayed surface can be quantified, which is larger than that of a smooth surface if the micropillar aspect ratio, Young's modulus ratio of the backing layer to the micropillars and separation distance between neighboring micropillars are appropriate. Detailed diagrams are respectively provided for the load sharing efficiency of all the micropillars and the comparison of the adhesion forces between micropillar arrayed and smooth surfaces with different geometric and material parameters, from which the design strategies of approaching equal load sharing regime and stronger adhesion force of the micropillar arrayed surface than that of the smooth one can be clearly found. The obtained results can not only deepen the understanding of the adhesion behavior of fibrillar surfaces but also provide theoretical guidance for achieving robust adhesion of the micropillar arrayed surfaces.

为了获得更好的附着力,受壁虎附着系统启发的微柱阵列表面受到了广泛关注。然而,与光滑表面相比,微柱阵列表面是否真的能增强界面粘附力的争论仍在继续。为了清楚地了解微柱阵列表面粘附力的影响因素,并为增强这种表面的粘附力提供一个标准,本文建立了一个包含弹性背层的微柱阵列表面的理论模型。在垂直均匀位移载荷作用下,微柱将从刚性基底上脱离。分析了分离过程中每个微柱的粘附行为以及整个粘附力受微柱几何形状、微柱材料和背衬层影响的变化规律。结果发现,随着微柱长宽比、背衬层与微柱的杨氏模量比以及相邻微柱之间的分离距离的增加,负载分担效率会增加,但随着样品尺寸的增加,负载分担效率会降低。如果微柱的长宽比、背衬层与微柱的杨氏模量比以及相邻微柱之间的间距合适,则可以量化微柱阵列表面的整个附着力,其大于光滑表面的附着力。详细的图表分别显示了所有微柱的负载分担效率,以及不同几何和材料参数下微柱阵列表面与光滑表面的附着力对比,从中可以清楚地发现接近等负载分担机制的设计策略,以及微柱阵列表面比光滑表面更强的附着力。所得结果不仅能加深对纤维素表面粘附行为的理解,还能为实现微柱阵列表面的稳健粘附提供理论指导。


High-efficient and reusable impact mitigation metamaterial based on compression-torsion coupling mechanism

Haifeng Ou, Lingling Hu, Yanbin Wang, Chang Liu

doi:10.1016/j.jmps.2024.105594

基于压缩-扭转耦合机制的高效、可重复使用的冲击减缓超材料

Lightweight and reusable materials are desired in engineering for mitigating repetitive impacts. However, the limitation of mitigation efficiency is always a problem in spite of various materials have been studied. And other issues need to be improved, such as bulky and poor load-bearing. There still exists challenge to design a reusable impact mitigation material with high efficient, lightweight and high stiffness. Here, a lightweight syndiotactic chiral metamaterial (SCM) with compression-torsion coupling effect (CTCE) is proposed and fabricated for repetitive impact mitigation. Impact experiments indicate that the proposed metamaterials exhibit significant superiorities in impact mitigation efficiency, lightweight, higher stiffness and less cells over the previously reported ones. In order to reveal the deeper mechanism of the superior properties, the band gaps of SCM with CTCE and isometric chiral metamaterial (ICM) without CTCE are analyzed and compared by transmissibility tests and numerical simulations. It is found that the extra energy dissipated by torsion caused by CTCE is the key factor for excellent mitigation performance, which enlarges the band gap to low-frequencies and prevents more waves pass through. To balance the mitigation performance and load carrying capacity, the gradient design strategy is proposed to cope with large impact loads with maintaining high mitigation efficiency, which is achieved by overlapping the band gaps of different cells to widen the band gap range. The mechanism of improving impact mitigation performance by CTCE revealed in the present work enlightens a new avenue to develop effective, reusable and lightweight buffer materials.

轻质和可重复使用的材料是减轻重复撞击的理想工程材料。然而,尽管已经对各种材料进行了研究,但缓解效率的限制始终是一个问题。还有一些问题需要改进,如体积庞大、承重能力差等。如何设计一种可重复使用的高效、轻质、高刚度的冲击缓解材料仍然是一个挑战。本文提出并制造了一种具有压缩-扭转耦合效应(CTCE)的轻质辛迪加手性超材料(SCM),用于重复冲击缓解。冲击实验表明,与之前报道的超材料相比,所提出的超材料在冲击缓解效率、轻量化、高刚度和少细胞等方面具有显著优势。为了揭示其卓越性能的深层机理,我们通过透射率测试和数值模拟,分析并比较了带 CTCE 的 SCM 和不带 CTCE 的等轴手性超材料(ICM)的带隙。结果发现,CTCE 产生的扭转所耗散的额外能量是实现出色缓和性能的关键因素,它扩大了低频带隙,阻止了更多的波通过。为了平衡缓和性能和承载能力,提出了梯度设计策略,通过重叠不同单元的带隙来扩大带隙范围,从而在保持高缓和效率的同时应对大的冲击载荷。本研究揭示的 CTCE 提高冲击缓解性能的机制为开发有效、可重复使用和轻质的缓冲材料提供了新的途径。


Mechanics of Materials

Preserving non-negative porosity values in a bi-phase elasto-plastic material under Terzaghi’s effective stress principle

Giuliano Pretti, William M. Coombs, Charles E. Augarde, Marc Marchena Puigvert, José Antonio Reyna Gutiérrez

doi:10.1016/j.mechmat.2024.104958

在特尔扎吉有效应力原理下保持双相弹塑性材料中的非负孔隙率值

Poromechanics is a well-established field of continuum mechanics which seeks to model materials with multiple phases, usually a stiff solid phase and fluid phases of liquids or gases. Applications are widespread particularly in geomechanics where Terzaghi’s effective stress is widely used to solve engineering soil mechanics problems. This approach assumes that the solid phase is incompressible, an assumption that leads to many advantages and simplifications without major loss of fidelity to the real world. Under the assumption of finite (as opposed to infinitesimal) strains, the poromechanics of two- or bi-phase materials gains complexity and while the compressible solid phase case has received attention from researchers, the incompressible case has received less. For the finite strain - incompressible solid phase case there is a fundamental issue with standard material models, in that for some loadings solid skeleton mass conservation is violated and negative Eulerian porosities are predicted. While, to the authors’ best knowledge, acknowledgement of this essential problem has been disregarded in the literature, an elegant solution is presented here, where the constraint on Eulerian porosity can be incorporated into the free energy function for a material. The formulation is explained in detail, soundly grounded in the laws of thermodynamics and validated on a number of illustrative examples.

孔隙力学是连续介质力学的一个成熟领域,旨在为具有多相(通常是坚硬的固相和液体或气体的流体相)的材料建模。其应用非常广泛,尤其是在地质力学中,特尔扎吉有效应力法被广泛用于解决工程土壤力学问题。这种方法假定固相是不可压缩的,这一假定带来了许多优点和简化,但并没有严重丧失对现实世界的忠实性。在有限应变(而非无穷小应变)的假设下,两相或双相材料的孔隙力学变得更加复杂,虽然可压缩固相情况受到了研究人员的关注,但不可压缩情况受到的关注较少。对于有限应变-不可压缩固相情况,标准材料模型存在一个基本问题,即在某些载荷下,固体骨架的质量守恒被违反,欧拉孔隙率被预测为负值。据作者所知,文献中一直忽略了这一基本问题,而本文提出了一个优雅的解决方案,即可以将对欧拉孔隙率的约束纳入材料的自由能函数中。本文详细解释了这一公式,以热力学定律为坚实基础,并通过大量示例进行了验证。


Thin-Walled Structures

EQUIVALENT LAYER-WISE THEORY FOR THE HYGRO-THERMO-MAGNETO-ELECTRO-ELASTIC ANALYSIS OF LAMINATED CURVED SHELLS

Francesco Tornabene, Matteo Viscoti, Rossana Dimitri

doi:10.1016/j.tws.2024.111751

层状曲面壳体的湿热磁电弹性分析等效分层理论

The paper presents a multifield formulation involving five different physical problems under the equilibrium thermodynamic conditions for laminated doubly-curved shell structures. More specifically, the study focuses on the coupling between the mechanical elasticity and the thermo-hygrometric problem, while also considering the magneto-electricity of the solid. The configuration variables are described with a generalized formulation based on the Equivalent Layer Wise (ELW) approach, taking into account higher order polynomial interpolations along the thickness direction. The fundamental relations are derived from the Master Balance principle and solved using the Navier's method. Furthermore, the three-dimensional response of the doubly-curved shell solid in terms of primary and secondary variables is recovered from the two-dimensional solution with a methodology based on the three-dimensional multifield balance equations and the Generalized Differential Quadrature (GDQ) numerical technique. Some examples are then presented in which panels of different curvatures and lamination schemes are investigated. The results are compared with success to those coming from three-dimensional numerical models developed with a commercial software. It is shown that the present analytical solution is a valid tool for modelling multifield problems for the evaluation of the response of doubly-curved shells under generalized external actions and pre-determined values of the configuration variables.

本文提出了一种多场公式,涉及层叠双曲壳结构平衡热力学条件下的五个不同物理问题。更具体地说,研究重点是机械弹性和热-偏振问题之间的耦合,同时还考虑了固体的磁电性。配置变量采用基于等效层智(ELW)方法的通用公式进行描述,并考虑了沿厚度方向的高阶多项式插值。基本关系由主平衡原理导出,并使用纳维法求解。此外,通过基于三维多场平衡方程和广义微分正交(GDQ)数值技术的方法,从二维解法中还原了双曲面壳体实体在主变量和次变量方面的三维响应。随后介绍了一些实例,研究了不同曲率和层压方案的面板。研究结果与使用商业软件开发的三维数值模型得出的结果进行了比较。结果表明,本分析解决方案是一种有效的工具,可用于多场问题建模,以评估双曲面壳体在广义外部作用和预定配置变量值下的响应。


Thermo-mechanical buckling and sound radiation characteristics of 3D graphene porous core curved sandwich panels with composite facings

R. Kiran Kumar Reddy, A.R. Veerappan, Nivish George, Vinod Bhagat

doi:10.1016/j.tws.2024.111753

带复合面层的三维石墨烯多孔芯曲面夹层板的热机械屈曲和声辐射特性

Buckling and sound radiation characteristics of curved sandwich panels subjected to combined thermo-mechanical loads are presented in the paper. The panel comprises a 3-D functionally graded graphene porous core sandwiched between FG-VΛ CNT reinforced composite face sheets (3DGrF-CF). The governing differential equations of 3DGrF-CF sandwich panels are derived using the parabolic shear deformation theory (PSDT), and the vibration responses are predicted using Navier’s approach. The vibration response thus obtained is fed into the Rayleigh integral to capture the acoustic pressure. The buckling and sound radiation characteristics were found to vary significantly with the core’s porosity coefficient and porosity grading pattern. However, the impact of this influence also depends on the magnitude of thermal & mechanical loading. This implies that selecting a core for acoustic comfort depends on the dominance of loading conditions and is illustrated using octave band analysis.

本文介绍了曲面夹层板在承受热机械综合载荷时的屈曲和声辐射特性。该夹芯板由三维功能分级石墨烯多孔夹芯和 FG-VΛ CNT 增强复合材料面片(3DGrF-CF)组成。利用抛物线剪切变形理论(PSDT)推导出了 3DGrF-CF 夹层板的控制微分方程,并利用纳维方法预测了振动响应。由此获得的振动响应被送入瑞利积分,以捕捉声压。研究发现,屈曲和声辐射特性随岩心的孔隙度系数和孔隙度分级模式的变化而显著不同。然而,这种影响也取决于热负荷和机械负荷的大小。这就意味着,要选择声学舒适度高的芯材,取决于加载条件的主导地位,并通过倍频程带分析加以说明。



来源:复合材料力学仿真Composites FEM
ACTMechanicalSystemInspireMarc振动复合材料通用声学理论材料控制曲面
著作权归作者所有,欢迎分享,未经许可,不得转载
首次发布时间:2024-11-06
最近编辑:2天前
Tansu
签名征集中
获赞 3粉丝 0文章 351课程 0
点赞
收藏
作者推荐

【新文速递】2024年3月3日复合材料SCI期刊最新文章

今日更新:Composite Structures 1 篇,Composites Part A: Applied Science and Manufacturing 1 篇,Composites Part B: Engineering 2 篇,Composites Science and Technology 1 篇Composite StructuresThermo-Mechanical analysis of laminated Doubly-Curved Shells: Higher order Equivalent Layer-Wise formulationFrancesco Tornabene, Matteo Viscoti, Rossana Dimitridoi:10.1016/j.compstruct.2024.117995层叠双曲面壳体的热力学分析:高阶等效层智公式The paper presents a refined two-dimensional formulation for the thermo-mechanical analysis of laminated doubly-curved shell structures under thermodynamic equilibrium conditions. Both the kinematic configuration variables and the temperature variation with respect to the natural equilibrium state are described with a generalized formulation, following the Equivalent Layer-Wise (ELW) approach employing higher order polynomials, along with some proper zigzag functions. The governing equations are derived from the stationary configuration of the Helmholtz free energy of the system, and a semi-analytical solution is found. In the post-processing phase, the Fourier-based Generalized Differential Quadrature (F-GDQ) is applied to recover the actual three-dimensional response of the doubly-curved shell solid, and very accurate results are obtained for the quantities of both mechanical and heat conduction problems. In addition, the integrals occurring in the theory are performed numerically with the Taylor-based Generalized Integral Quadrature (GTIQ), showing a high level of accuracy with a reduced number of sample points. The model is validated in some case studies where the accuracy of the model is shown, and the numerical predictions are successfully compared with those of refined three-dimensional numerical simulations. After that, an extensive set of parametric investigations is reported, pointing out the effects of the panel’s curvature, lamination schemes and different levels of coupling on the thermo-mechanical structural behavior of the investigated panels.本文针对热力学平衡条件下的层叠双曲面壳体结构的热机械分析,提出了一种改进的二维公式。运动构型变量和相对于自然平衡状态的温度变化均采用通用公式进行描述,该公式采用了高阶多项式和一些适当的之字形函数的 "等效分层"(ELW)方法。根据系统的亥姆霍兹自由能的静态配置推导出控制方程,并找到半解析解。在后处理阶段,应用基于傅立叶的广义微分正交(F-GDQ)来恢复双曲面壳体固体的实际三维响应,并获得了机械和热传导问题的非常精确的结果。此外,理论中出现的积分采用基于泰勒的广义积分正交(GTIQ)进行数值计算,在样本点数量减少的情况下显示出很高的精度。该模型在一些案例研究中得到了验证,证明了模型的准确性,并成功地将数值预测与精细的三维数值模拟进行了比较。随后,报告了一系列广泛的参数研究,指出了面板的曲率、层压方案和不同程度的耦合对所研究面板的热机械结构行为的影响。Composites Part A: Applied Science and ManufacturingLightweight zirconium modified carbon–carbon composites with excellent microwave absorption and mechanical propertiesWeikang Tang, Shun Dong, Tangyin Cui, Jianqiang Xin, Yongshuai Xie, Guiqing Chen, Changqing Hong, Xinghong Zhangdoi:10.1016/j.compositesa.2024.108102具有优异微波吸收能力和机械性能的轻质锆改性碳-碳复合材料With the rapid development of space technology, multi-functional materials with advantages such as heat insulation, lightweight, and electromagnetic (EM) wave absorption have gained broad application prospects. Since porous carbon fiber reinforced carbon (C/C) composites often have lightweight and high heat insulation properties, improving their mechanical and electromagnetic wave absorbing properties will significantly expand their application. In this study, a new kind of zirconium-modified C/C (Zr-C/C) composites prepared by polymer infiltration and pyrolysis using zirconium-modified phenolic resin is presented. By adjusting the content of Zr, the compressive strengths of the composites are increased up to 48% compared with the composites without Zr, while the thermal insulation properties are little changed. The incorporation of zirconium can make the composites exhibit better microwave absorption performance to some extent, and Zr-C/C composites with 10% zirconium have the best microwave absorption performance among all the samples. The excellent electromagnetic wave absorption performance of Zr-C/C composites is attributed to the enhanced interfacial polarization effect and the improved electrical conductivities of the material due to its internal carbon microsphere structure. Multi-functional Zr-C/C composites that combine lightweight, high thermal insulation, high compressive strength, and high electromagnetic wave absorption have obvious applications in fields such as stealth aircraft. Therefore, this work provides a new way to prepare multi-functional materials.随着航天技术的飞速发展,具有隔热、轻质和吸收电磁波等优点的多功能材料获得了广阔的应用前景。由于多孔碳纤维增强碳(C/C)复合材料通常具有轻质和高隔热性能,因此改善其机械性能和电磁波吸收性能将大大拓展其应用领域。本研究利用锆改性酚醛树脂,通过聚合物浸渗和热解制备了一种新型锆改性碳纤维增强碳(C/C)复合材料(Zr-C/C)。与不含锆的复合材料相比,通过调整锆的含量,复合材料的抗压强度提高了 48%,而隔热性能变化不大。锆的加入能在一定程度上使复合材料表现出更好的微波吸收性能,其中含 10%锆的 Zr-C/C 复合材料的微波吸收性能是所有样品中最好的。Zr-C/C 复合材料优异的电磁波吸收性能得益于界面极化效应的增强以及材料内部碳微球结构带来的导电性能的改善。集轻质、高隔热、高抗压强度和高电磁波吸收能力于一身的多功能 Zr-C/C 复合材料在隐形飞机等领域具有明显的应用前景。因此,这项工作为制备多功能材料提供了一条新途径。Composites Part B: EngineeringThe role of nanoclay in processing immiscible polypropylene and poly (ethylene terephthalate) waste blends using twin screw extrusionShawn Martey, Mansoureh Jamalzadeh, Wan-Ting Chen, Margaret J. Sobkowiczdoi:10.1016/j.compositesb.2024.111320 纳米粘土在使用双螺杆挤出机加工不相溶聚丙烯和聚(乙烯对苯二甲酸乙二酯)废料混合物中的作用Polypropylene and poly(ethylene terephthalate) waste were blended with different types of nanoclay (cloisite Na+, cloisite 20A and CT4270) to understand the role of nanoclay in immiscible polymer blends. The blend morphology was investigated using scanning electron microscopy, the dispersion of the nanoclay was characterized using wide angle x-ray diffraction (WAXD) and rheology. WAXD results showed partial exfoliation for cloisite Na+ and intercalation for cloisite 20A and CT4270. It was predicted that cloisite Na + settled in the PET phase while cloisite 20A settled at the interface of PP and PET. Morphology analysis showed that increasing the concentration of nanoclay in the blend decreased the droplet size. The nanoclay was shown to inhibit coalescence of the droplets causing a decrease due to its rigidity.将聚丙烯和聚对苯二甲酸乙二酯废料与不同类型的纳米土(cloisite Na+、cloisite 20A 和 CT4270)混合,以了解纳米土在不相溶聚合物共混物中的作用。使用扫描电子显微镜研究了共混物的形态,使用广角 X 射线衍射(WAXD)和流变学表征了纳米土的分散性。WAXD 结果显示,钙钛矿 Na+ 部分剥离,而钙钛矿 20A 和 CT4270 则发生了插层。据预测,loisite Na + 沉淀在 PET 相中,而 cloisite 20A 沉淀在 PP 和 PET 的界面上。形态分析表明,增加混合物中纳米土的浓度会减小液滴尺寸。纳米粘土可抑制液滴的凝聚,从而降低液滴的硬度。Influence of unidirectional composite failure envelope shape on predicting compressive failure of a laminate with a filled holeIvan R. Cózar, José M. Guerrero, Pere Maimí, Albertino Arteiro, Santiago García-Rodríguez, Mélanie Herman, Albert Turondoi:10.1016/j.compositesb.2024.111352单向复合材料破坏包络线形状对带填充孔层压破坏预测的影响In recent decades, several computational models have emerged at the mesoscale for predicting the failure development and strength of composite materials. Nevertheless, the intricate failure mechanisms of composites pose a formidable challenge in developing models capable of consistently reproducing diverse sets of experimental data. Furthermore, the absence of standardised multiaxial tests has hindered consensus on failure envelopes and criteria for composites. In this work, an in-house constitutive model implemented in a finite element code is employed to predict the failure strength of several filled hole compressive carbon/epoxy experimental tests, varying in stacking sequences, sizes, bolt preloads, and other parameters. The influence the selected failure criterion has on the predictions is analysed. The findings indicate a large impact of the failure envelope on both the ultimate compressive strength and developed failure mechanisms. Therefore, the correct adjustment of the failure criteria can be as relevant as defining accurately the material input parameters. These results emphasise the importance of accurately establishing failure envelopes, rather than overemphasising the development of complex models.近几十年来,在中尺度上出现了一些用于预测复合材料失效发展和强度的计算模型。然而,复合材料的失效机理错综复杂,这对开发能够持续再现各种实验数据的模型提出了严峻的挑战。此外,标准化多轴测试的缺乏也阻碍了对复合材料失效包络和标准达成共识。在这项工作中,采用了一个在有限元代码中实施的内部构成模型来预测多个填充孔压缩碳/环氧实验测试的破坏强度,这些测试在堆叠顺序、尺寸、螺栓预紧力和其他参数方面各不相同。分析了所选失效准则对预测结果的影响。研究结果表明,失效包络线对极限抗压强度和失效机理都有很大影响。因此,正确调整失效标准与准确定义材料输入参数同样重要。这些结果强调了准确确定破坏包络的重要性,而不是过分强调复杂模型的开发。Composites Science and TechnologyA honeycomb-inspired carboxymethyl chitosan-covalently link NH2-black phosphorene biobased cellulose green nanocomposites with tremendously enhancement fire safety and thermal conductivityKunxin Wang, Zhencai Qu, Hui Yang, Guoming Yuan, Xiu-e Li, Zhijun Liu, Yanhan Tao, Yang Li, Kun Wu, Jun Shidoi:10.1016/j.compscitech.2024.110535 一种蜂窝状羧甲基壳聚糖共价连接 NH2-黑磷烯生物基纤维素绿色纳米复合材料,可大幅提高防火安全性和导热性能Biobased carboxymethyl chitosan-modified black phosphorene (BP-CMC) was prepared through an amidation reaction between amino group functionalized black phosphorene (NH2-BP) and CMC. Density functional theory (DTF) express that the adsorption energy between urea and phosphene is −6.28 eV, indicating a strong interaction. The resulting BP-CMC was further applied to reinforce the mechanical, flame-retardant and thermal conductivity performance of honeycomb cellulose nanofiber (CNF) film via vacuum filtration. Cone calorimetry test (CCT) result exhibits that the introduction of 30 wt% BP-CMC significantly promoted the fire safety of CNF. For instance, a 98.41% reduction in smoke production rate (SPR), 92.00 % decline in CO release and a 61.31% decrease in heat release rate (HRR) were observed compared to neat CNF. Furthermore, Thermogravimetric infrared (TG-IR) indicates a significant decrease in the release of flammable gases. Raman spectra verify that the incorporation of 30 wt% BP-CMC improves the graphitization degree of residual chars, thus limiting the transfer of heat and oxygen. The improvement in fire safety is attributed to the formation of an intumescent flame-retardant system, which is rich in carbon source (CMC), acid source (BP) and gas source (amino). Simultaneously, the introduction of 30 wt% BP-CMC into CNF leads to considerable enhancement in thermal conductivity (up to 17.49 %), thermal diffusion (utmost to 43.45 %) and heat capacity (increased by 19.23 %). Moreover, the 30 wt % addition of BP-CMC into CNF possesses excellent mechanical properties with the improvement of toughness (increased by 143.50 %) and tensile strength (increased by 140.90 %). This strategy not only provides a new strategy for functionalizing BP but also upgrades the application potential of BP nanosheets in the fire safety of polymer composite films.通过氨基官能化黑磷烯(NH2-BP)与 CMC 的酰胺化反应制备了生物基羧甲基壳聚糖改性黑磷烯(BP-CMC)。密度泛函理论(DTF)表明,脲与磷烯之间的吸附能为 -6.28 eV,表明存在很强的相互作用。通过真空过滤,得到的 BP-CMC 进一步用于增强蜂窝纤维素纳米纤维(CNF)薄膜的机械、阻燃和导热性能。锥形量热试验(CCT)结果表明,30 wt% BP-CMC 的引入显著提高了 CNF 的防火安全性。例如,与纯 CNF 相比,产烟率(SPR)降低了 98.41%,一氧化碳释放量减少了 92.00%,热释放率(HRR)降低了 61.31%。此外,热重红外(TG-IR)显示可燃气体的释放量显著减少。拉曼光谱验证了 30 wt% BP-CMC 的加入提高了残留炭的石墨化程度,从而限制了热量和氧气的传递。防火安全性的提高归功于富含碳源(CMC)、酸源(BP)和气源(氨基)的膨胀阻燃体系的形成。同时,在 CNF 中引入 30 wt%的 BP-CMC 可显著提高导热率(高达 17.49%)、热扩散率(高达 43.45%)和热容量(提高 19.23%)。此外,在氯化萘纤维中添加 30 wt % 的 BP-CMC 可提高韧性(提高 143.50 %)和拉伸强度(提高 140.90 %),从而具有优异的机械性能。这种策略不仅为 BP 功能化提供了一种新策略,还提升了 BP 纳米片在聚合物复合薄膜防火安全方面的应用潜力。来源:复合材料力学仿真Composites FEM

未登录
还没有评论
课程
培训
服务
行家
VIP会员 学习 福利任务 兑换礼品
下载APP
联系我们
帮助与反馈