Composites Science and Technology最新文献_第2页

Sulfur Co-polymer as a universal adhesive to construct segregated structure in cross-linked rubber toward improved conductive and mechanical properties 硫磺共聚物作为一种通用粘合剂，可在交联橡胶中构建离析结构，从而改善导电性能和机械性能

IF 8.3 1区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composites Science and Technology

Pub Date : 2024-11-20 DOI: 10.1016/j.compscitech.2024.110964

Shu Wang, Zhenghai Tang, Yilin Xiao, Dong Wang, Baochun Guo, Liqun Zhang

Creating segregated structure within composites can significantly improve electrical conductivity but usually compromises mechanical properties. In this contribution, we introduced a straightforward and universal method to fabricate segregated rubber composites with a rare integration of high electrical conductivity and mechanical robustness by utilizing an inverse vulcanized copolymer (SP) as an adhesive to bind the segregated domains. Specifically, sulfur-crosslinked butadiene styrene rubber (SBR) granules were mixed with SP and carbon nanotubes (CNTs), followed by compression molding. CNTs embedded within SP are strategically dispersed along the boundaries of SBR granules, and the reaction of SP with SBR granules creates covalent bonding among the segregated domains and increases their crosslinking density. The segregated skeleton constituted by highly interconnected CNTs is robust, which imparts the composites with high electrical conductivity that is stable upon deformations and is able to heal after damage. In addition, the rigid segregated skeleton preferentially ruptures to dissipate enormous energy, and the cohesive interphase facilitates chain finite extensibility in the highly crosslinked segregated domains, resulting in remarkable enhancements on the tensile strength and modulus of the composites. The universality of this strategy is further demonstrated by using ground waste tyre rubber as matrix and boron nitride sheets as filler.

在复合材料中制造离析结构可显著提高导电性，但通常会影响机械性能。在这篇论文中，我们介绍了一种直接而通用的方法，即利用反硫化共聚物（SP）作为粘合剂来粘合离析畴，从而制造出兼具高导电性和机械坚固性的离析橡胶复合材料。具体来说，硫交联丁苯橡胶（SBR）颗粒与 SP 和碳纳米管（CNT）混合，然后进行压缩成型。嵌入 SP 中的 CNT 沿 SBR 粒料的边界战略性地分散，SP 与 SBR 粒料的反应在分离域之间形成共价键，并增加了其交联密度。由高度相互连接的 CNT 构成的分隔骨架非常坚固，这使得复合材料具有高导电性，在变形时非常稳定，并且在损坏后能够愈合。此外，刚性偏析骨架会优先断裂以耗散巨大能量，而内聚相则会促进高度交联偏析域的链有限延伸性，从而显著提高复合材料的拉伸强度和模量。使用磨碎的废轮胎橡胶作为基体，氮化硼片作为填料，进一步证明了这一策略的普遍性。

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引用次数: 0

Enhance the piezoelectricity of poly(vinylidene fluoride) through co-crystal with polycaprolactone 通过与聚己内酯共晶体增强聚偏氟乙烯的压电性

IF 8.3 1区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composites Science and Technology

Pub Date : 2024-11-19 DOI: 10.1016/j.compscitech.2024.110973

Zhiwei Ye, Juan Yi, Yibo Zhang, Chuanxi Xiong

The strategies of solid solution and doping have been well-established obtaining high piezoelectric ceramics, achieving a significant increase in the piezoelectric coefficient. Nevertheless, there is a paucity of research investigating this strategy in polymer piezoelectric materials. In this work, we present a novel approach to co-crystal formation between polycaprolactone (PCL) and poly(vinylidene fluoride) (PVDF), which markedly enhances the piezoelectricity of PVDF. The formation of a co-crystal results in a notable reduction in the crystal size of PVDF, an increase in the interface between the crystalline and amorphous regions, and the directional arrangement of dipoles under an electric field. The piezoelectric coefficient of the 3 % PCL/PVDF film is approximately twice that of the commercial PVDF film (22.0 pC/N), and the sensor device exhibits favorable linear sensing characteristics. The present study proposes a novel strategy for the development of films with exceptional piezoelectric properties.

固溶和掺杂策略在获得高压电陶瓷方面已得到广泛应用，可显著提高压电系数。然而，在聚合物压电材料中采用这种策略的研究还很少。在这项工作中，我们提出了一种在聚己内酯（PCL）和聚偏二氟乙烯（PVDF）之间形成共晶体的新方法，这种方法显著增强了 PVDF 的压电性。共晶体的形成明显减小了 PVDF 的晶体尺寸，增加了晶体区和无定形区之间的界面，并使偶极子在电场作用下定向排列。3 % PCL/PVDF 薄膜的压电系数约为商用 PVDF 薄膜的两倍（22.0 pC/N），传感器装置表现出良好的线性传感特性。本研究为开发具有优异压电特性的薄膜提出了一种新策略。

引用次数: 0

Vertically aligned liquid metal thermal pad with excellent electromagnetic shielding and ultra-high compressibility 垂直排列的液态金属导热垫具有出色的电磁屏蔽和超高的可压缩性

IF 8.3 1区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composites Science and Technology

Pub Date : 2024-11-19 DOI: 10.1016/j.compscitech.2024.110974

Yisimayili Tuersun , Pingjun Luo , Xu Huang , Mingdeng Huang , Yilimiranmu Rouzhahong , Chu Sheng

With the increasing integration level of modern electronics, flexible highly thermally conductive and electromagnetic interference shielding (EMI) materials were urgently demanded in electronic devices. Traditionally carbon or solid metal fillers are widely used as a reinforcement to fabricate a flexible thermally conductive and EMI shielding materials. However Due to the trade-off between mechanical and thermal properties, it is difficult to further improve the performance of solid filler/polymer composites. Here in this work based on the intrinsic excellent electrical and thermal conductivity of liquid metal (LM), we embedded the LM network structure vertically in the silicone gel and fabricated a vertically aligned LM(VALM) composites. Compared to the randomly dispersed LM composites, VALM composite exhibits high through plane thermal conductivity (κ_⊥: 6.08 W/m·K) and excellent EMI shielding efficiency (SE) (minimum and maximum EMI SE for VALM2 were 33.2 dB and 39.5 dB). In addition, due to the fluidic nature of LM, composite materials exhibit excellent softness and flexibility (compression modulus of 0.56 MPa). Practical heat dissipation test results and EMIS efficiencies demonstrate usefulness of VALM composite in next-generation electronics.

随着现代电子产品集成度的不断提高，电子设备迫切需要柔性高导热和电磁干扰屏蔽（EMI）材料。传统上，碳或固体金属填料被广泛用作制造柔性导热和电磁干扰屏蔽材料的增强材料。然而，由于机械性能和热性能之间的权衡，很难进一步提高固体填料/聚合物复合材料的性能。在这项工作中，我们基于液态金属（LM）固有的优异导电性和导热性，将 LM 网络结构垂直嵌入硅凝胶中，制备出垂直排列的 LM（VALM）复合材料。与随机分散的 LM 复合材料相比，VALM 复合材料具有较高的通平面热导率（κ⊥：6.08 W/m-K）和出色的 EMI 屏蔽效率（SE）（VALM2 的最小和最大 EMI SE 分别为 33.2 dB 和 39.5 dB）。此外，由于 LM 的流体性质，复合材料表现出卓越的柔软性和灵活性（压缩模量为 0.56 兆帕）。实际散热测试结果和 EMIS 效率证明了 VALM 复合材料在下一代电子产品中的实用性。

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引用次数: 0

3D printing lignin carbonized nanotube and cellulose nano fiber aerogel for wearable pressure sensors 用于可穿戴压力传感器的 3D 打印木质素碳化纳米管和纤维素纳米纤维气凝胶

IF 8.3 1区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composites Science and Technology

Pub Date : 2024-11-19 DOI: 10.1016/j.compscitech.2024.110976

Xiaoqing Du , Qi Chen , Qiqi Zhou , Yufan Zhou , Feng Wang , Wangjie Xu , Yulin Zhan , Man Jiang

The nanocellulose represents an important sustainability and chemical stability candidate for conductive 3D aerogel sensors, while introducing additional conductive additives is necessary. Herein, the as developed lignin derived carbonized nanotube (LCNT) in our lab was adopted as conductive ingredient to fabricate cellulose nanofiber (CNF) based composite aerogel by 3D printing. Specifically, the as-prepared LCNT/CNF composite aerogel with ratio of 85:15 in weight presented homogeneous porous morphology with well dispersed and penetrated LCNT in CNF porous matrix, providing a piezoresistive type pressure sensor. Stable signals were achieved under testing range from 0.2 to 9.8 kPa, with response time between 100 and 200 ms, related to the testing accuracy. The mechanical property of the as-prepared composite aerogel was found to be satisfactory. Under a constant 30 % compression strain for 1000 cycles, 92.5 % stress retention was maintained, and the ultimate stress was tested to be 16.64 kPa. This work provided a customized wearable pressure sensor with satisfactory comprehensive performance made completely from cellulose and lignin renewable natural polymers.

纳米纤维素是导电三维气凝胶传感器的重要可持续性和化学稳定性候选材料，而引入额外的导电添加剂则是必要的。在此，我们采用实验室开发的木质素衍生碳化纳米管（LCNT）作为导电成分，通过三维打印技术制备了基于纤维素纳米纤维（CNF）的复合气凝胶。具体而言，制备出的 LCNT/CNF 复合气凝胶的重量比为 85:15，呈现出均匀的多孔形态，LCNT 在 CNF 多孔基质中充分分散和渗透，提供了一种压阻式压力传感器。在 0.2 至 9.8 kPa 的测试范围内均可获得稳定的信号，响应时间在 100 至 200 ms 之间，这与测试精度有关。所制备的复合气凝胶的机械性能令人满意。在 30% 的恒定压缩应变下循环 1000 次，应力保持率为 92.5%，极限应力为 16.64 kPa。这项研究提供了一种完全由纤维素和木质素可再生天然聚合物制成的定制可穿戴压力传感器，其综合性能令人满意。

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引用次数: 0

Designable alignment of reclaimed carbon fiber by soft-lock pressing for remanufacturing multifunctional flexible heater 通过软锁压制对再生碳纤维进行可设计的排列，用于再制造多功能柔性加热器

IF 8.3 1区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composites Science and Technology

Pub Date : 2024-11-18 DOI: 10.1016/j.compscitech.2024.110966

Yu Tian , Shuran Li , Weidong Zhu , Keping Yan , Yinglin Ke

The utilization of reclaimed carbon fiber (rCF) in remanufacturing processes presents a sustainable solution for reducing carbon footprint and promoting circular economy principles. In this study, we propose a simple and direct universal soft-lock pressing method to achieve the controlled formation and strategic arrangement of highly ordered fiber arrays. Experimental results demonstrate that the aligned rCF array exhibits hydrophobic properties due to its continuous micro-rounded arch morphology on the surface. Combined with rapid and uniform Joule heating, the multifunctional flexible heater remanufactured based on rCF arrays shows promising prospects for preventing ice formation and facilitating rapid de-icing in low-temperature environments. Notably, this method can effectively utilize the directional properties of rCF to construct temperature gradients, enhancing heat distribution and overall performance in heating and de-icing applications. Overall, using soft-lock pressing for the remanufacturing of rCF multifunctional flexible heaters represents a convergence of sustainability, advanced materials, and functional design, and is an important exploration and leadership in closing the recycling loop through various innovative pathways.

在再制造过程中利用再生碳纤维（rCF）是减少碳足迹和促进循环经济原则的可持续解决方案。在本研究中，我们提出了一种简单直接的通用软锁压制方法，以实现高度有序的纤维阵列的可控形成和策略排列。实验结果表明，排列有序的 rCF 阵列表面具有连续的微圆拱形形态，因而具有疏水特性。结合快速均匀的焦耳加热，基于 rCF 阵列再制造的多功能柔性加热器在防止结冰和促进低温环境下的快速除冰方面显示出广阔的前景。值得注意的是，这种方法能有效利用 rCF 的定向特性来构建温度梯度，从而增强热量分布，提高加热和除冰应用的整体性能。总之，利用软锁压制技术再制造 rCF 多功能柔性加热器代表了可持续发展、先进材料和功能设计的融合，是通过各种创新途径实现循环利用闭环的重要探索和引领。

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引用次数: 0

Safe and negligible-loss overcurrent protection: A novel macromolecular voltage stabilizer for conductive polymer composites 安全且损耗可忽略不计的过流保护：用于导电聚合物复合材料的新型大分子稳压器

IF 8.3 1区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composites Science and Technology

Pub Date : 2024-11-16 DOI: 10.1016/j.compscitech.2024.110965

Xuhuang Chen , Jiaqi Gao , Yinghao Qi , Chuanchuan Dai , Zhaoxin Li , Yu Wu , Peng Yu , Siwen Bi

The balance between safety issues and low loads remains a major obstacle toward large-scale applications of conductive polymer composites (CPCs) based over-current protection. Elevating the conductive filler concentration in CPCs is a potential strategy to reduce initial resistivity for decreased load, but compromise positive temperature coefficient (PTC) performance and voltage breakdown strength. Here, a novel type of macromolecular voltage stabilizer is synthesized by fluorine rubber and ferrocene to optimize the comprehensive properties of CPCs with low resistivity. The voltage stabilizer provides CPCs with a high voltage breakdown strength of up to 54V with maintaining an extremely low initial resistivity. Such CPCs also have an enhanced PTC intensity, improved instability voltage threshold, suppressed NTC effect, and good reproducibility up on/off switching. Based on tunnel effect, these improved properties can be interpreted by the reduction of charge transfer impact on the degradation of the polymer matrix. This work suggests the great potential of using these unique additives and theoretical investigations for overcurrent protection or insulating material.

安全问题与低负载之间的平衡仍然是大规模应用基于过流保护的导电聚合物复合材料（CPC）的主要障碍。提高 CPC 中导电填料的浓度是降低初始电阻率以减少负载的潜在策略，但会影响正温度系数（PTC）性能和电压击穿强度。本文通过氟橡胶和二茂铁合成了一种新型高分子电压稳定剂，以优化低电阻率 CPC 的综合性能。这种电压稳定剂使 CPC 在保持极低初始电阻率的同时，还具有高达 54V 的高电压击穿强度。这种 CPC 还具有增强的 PTC 强度、改善的不稳定电压阈值、抑制的 NTC 效应以及良好的开关再现性。基于隧道效应，电荷转移对聚合物基质降解的影响减小，从而解释了这些改进的特性。这项研究表明，将这些独特的添加剂和理论研究用于过流保护或绝缘材料具有巨大的潜力。

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引用次数: 0

RVE Simulations of short fiber reinforced polyamide: Direct and inverse matrix parameter identification in view of the semi-crystalline polymer structure 短纤维增强聚酰胺的 RVE 模拟：根据半结晶聚合物结构确定直接和反向基体参数

IF 8.3 1区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composites Science and Technology

Pub Date : 2024-11-16 DOI: 10.1016/j.compscitech.2024.110961

Paul Wetzel , Benjamin Schneider , Anna Katharina Sambale , Markus Stommel , Jan-Martin Kaiser

This paper investigates the modeling capabilities of computational homogenization for the mechanical behavior of short fiber reinforced polyamide. Simulations on a representative volume element (RVE) with elastic fibers and an elastic–plastic matrix are compared to tensile experiments on specimens taken in parallel and transversal direction from injection molded plates. In view of the semi-crystalline polymer structure, focus is put on identifying the matrix parameters through two alternative methods:

First, the matrix parameters are identified directly using tensile experiments on a non-nucleated and a nucleated unreinforced polyamide. In the RVE computations based on the non-nucleated grade, the composite stress–strain behavior is somewhat underestimated, and with the nucleated grade, the behavior is slightly overestimated. To explain this, the semi-crystalline polymer structure is studied. Polarized light microscopy images reveal that the non-nucleated grade has a coarser and the nucleated grade a finer spherulite structure, compared to the matrix present in the composite. However, the degree of crystallinity measured by differential scanning calorimetry is in a similar range.

As an alternative, the matrix parameters are identified inversely by fitting the RVE model to the composite tensile experiments. As uncertainties with respect to the matrix material as well as possibly remaining simplifications in the micromechanical model are compensated for, this reverse engineering approach allows for a very good fit.

本文研究了短纤维增强聚酰胺机械行为的计算均质化建模能力。将具有弹性纤维和弹塑性基体的代表性体积元素（RVE）模拟与注塑板平行和横向试样的拉伸实验进行了比较。鉴于半结晶聚合物结构，重点放在通过两种替代方法确定基体参数上：首先，直接使用无核和有核非增强聚酰胺的拉伸实验确定基体参数。在基于无核牌号的 RVE 计算中，复合材料的应力-应变行为被低估了一些，而在有核牌号中，复合材料的应力-应变行为被高估了一些。为了解释这一现象，我们对半结晶聚合物结构进行了研究。偏光显微镜图像显示，与复合材料中存在的基体相比，无核级具有较粗的球状结构，而有核级则具有较细的球状结构。然而，通过差示扫描量热法测量的结晶度范围相似。作为替代方法，基体参数是通过将 RVE 模型拟合到复合材料拉伸实验中反向确定的。由于补偿了基体材料的不确定性以及微机械模型中可能存在的简化，这种逆向工程方法可以获得非常好的拟合效果。

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引用次数: 0

Egg white-derived nanocomposite microspheres for alveolar bone defects management 用于牙槽骨缺损管理的蛋清纳米复合微球

IF 8.3 1区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composites Science and Technology

Pub Date : 2024-11-10 DOI: 10.1016/j.compscitech.2024.110962

Yi Hou , Mengmeng Jin , Dan Sun , Songsong Zhu

In this study, we developed a new class of nanocomposite microspheres comprising of Ca²⁺ crosslinked chicken egg white (EW) and Zn-doped mesoporous silica nanoparticles (Zn–SiO₂), targeting the challenging alveolar defect repair applications. We drew inspiration from the “Chinese century egg” preservation techniques to crosslink the EW protein using Ca²⁺ ions under alkali conditions and this has led to a novel alkali-ionic (ai) cross-linked EW network with enhanced mechanical stability. Molecular dynamic simulation was deployed to elucidate the protein crosslinking mechanisms within the microspheres. Zn-doped mesoporous silica nanoparticles (Zn–SiO₂) were introduced as degradable functional nanofillers. Results show that the unique Zn–SiO₂/ai-EW nanocomposite microspheres have enhanced mechanical strength, desirable degradation profile and biomineralization capabilities. In vitro and in vivo studies show that with the gradual released Ca²⁺ from the EW matrix can promote osteogenic differentiation; Si⁴⁺ and Zn²⁺ can modulate the immune microenvironment and enhanced angiogenesis. The promising results have demonstrated the strong potential of Zn–SiO₂/ai-EW composite microspheres for alveolar bone repair applications.

在这项研究中，我们针对具有挑战性的肺泡缺损修复应用，开发了一种由 Ca2+ 交联鸡蛋白（EW）和掺锌介孔二氧化硅纳米颗粒（Zn-SiO2）组成的新型纳米复合微球。我们从 "中华世纪坛蛋 "的保存技术中汲取灵感，利用 Ca2+ 离子在碱性条件下交联 EW 蛋白，从而形成了一种新型的碱-离子（ai）交联 EW 网络，并增强了其机械稳定性。分子动力学模拟用于阐明微球内的蛋白质交联机制。此外，还引入了掺锌介孔二氧化硅纳米粒子（Zn-SiO2）作为可降解的功能性纳米填料。结果表明，独特的 Zn-SiO2/ai-EW 纳米复合微球具有更高的机械强度、理想的降解特性和生物矿化能力。体外和体内研究表明，随着 EW 基质中 Ca2+ 的逐渐释放，可促进成骨分化；Si4+ 和 Zn2+ 可调节免疫微环境并增强血管生成。这些可喜的结果证明了 Zn-SiO2/ai-EW 复合微球在牙槽骨修复方面的巨大应用潜力。

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引用次数: 0

Anti-interference flexible temperature-sensitive/strain-sensing aerogel fiber for cooperative monitoring of human body temperature and movement information 用于协同监测人体温度和运动信息的抗干扰柔性温敏/应变传感气凝胶纤维

IF 8.3 1区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composites Science and Technology

Pub Date : 2024-11-09 DOI: 10.1016/j.compscitech.2024.110955

Jiayi Fu , Jian Tang , Shidong Ma , Zhijuan Pan , Ruoxin Li , Yuting Wu , Tao Yan

In recent years, multi-functional flexible sensing fibers capable of detecting various physical and chemical stimuli capabilities have made significant advancements. However, the cross-sensitivity of the sensing materials to other stimuli can considerably reduce their sensitivity and accuracy of these multifunctional fibers. In this study, we initially fabricated a blending type (BAF) and a core-sheath type (CAF) strain-sensing aerogel fiber using an optimized one-step wet spinning process. Then, we coated the aerogel fiber with cholesteric liquid crystal as the middle layer and waterborne polyurethane as the outer layer to obtain a temperature-sensitive/strain-sensing aerogel fiber (TSAF). TSAF demonstrates distinct multi-model strain sensing performance, enabling the detection of tensile strains (0.1–111.5 %), bending strains (40°–160°), and compression strains. Moreover, within the ultra-narrow temperature range of 34 °C–38 °C, TSAF undergoes reversible color transformations from yellow-green-blue-purple, against both bright and dark backgrounds. This unique feature offered high sensitivity, rapid response time, and diverse color variations. By integrating fibers into clothing, a collaborative sensing system can be established to simultaneously monitor human physiology and movement information. These advancements hold significant potential for applications in smart clothing, medical care, and other fields.

近年来，能够检测各种物理和化学刺激的多功能柔性传感纤维取得了重大进展。然而，传感材料对其他刺激的交叉敏感性会大大降低这些多功能纤维的灵敏度和准确性。在本研究中，我们采用优化的一步湿法纺丝工艺，初步制备了一种混合型（BAF）和一种芯鞘型（CAF）应变传感气凝胶纤维。然后，我们在气凝胶纤维的中间层涂覆了胆甾液晶，在外层涂覆了水性聚氨酯，从而获得了温敏/应变传感气凝胶纤维（TSAF）。TSAF 具有独特的多模式应变传感性能，可检测拉伸应变（0.1-111.5 %）、弯曲应变（40°-160°）和压缩应变。此外，在 34 ℃-38 ℃ 的超窄温度范围内，TSAF 可在明亮和昏暗的背景下发生黄绿-蓝紫色的可逆颜色转换。这一独特功能具有灵敏度高、响应速度快和色彩变化多样等特点。通过将纤维集成到服装中，可以建立一个协同传感系统，同时监测人体生理和运动信息。这些进步为智能服装、医疗保健和其他领域的应用带来了巨大潜力。

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引用次数: 0

Dual covalent bond induced high thermally conductive polyimide composite films based on CNT@CN complex filler 基于 CNT@CN 复合填料的双共价键诱导型高导热聚酰亚胺复合薄膜

IF 8.3 1区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composites Science and Technology

Pub Date : 2024-11-09 DOI: 10.1016/j.compscitech.2024.110963

Fan Wang , Xiaodi Dong , Guangyi Liu , Jing-Hui Gao , Xu Wang , Jun-Wei Zha

Polyimide (PI) possesses excellent high-temperature resistance, insulation properties, and mechanical properties, making it widely used as a flexible printed circuit board substrate and high-temperature electrical insulation material. However, the irregular arrangement of PI molecules results in a relatively low thermal conductivity. This work utilizes the active groups on the surface of carboxylated multi-walled carbon nanotubes (MWCNTs) and carbon nitride nanosheets (CNNS) to obtain CNTs@CN complex fillers containing covalent bonds. The thermal conductivity of CNTs@CN/PI with double covalent bonds can be up to 6.63 W m⁻¹ K⁻¹. The covalent bonds between fillers and fillers as well as between fillers and the matrix provide efficient and continuous pathways for phonon transmission. Additionally, finite element analysis further reveals the heat transfer mechanism of the CNTs@CN/PI composite film. Therefore, this will provide a feasible solution to enhance the thermal conductivity of PI, making it more promising for applications in electronic devices.

聚酰亚胺（PI）具有优异的耐高温性能、绝缘性能和机械性能，因此被广泛用作柔性印刷电路板基材和高温电气绝缘材料。然而，PI 分子的不规则排列导致其热导率相对较低。本研究利用羧化多壁碳纳米管（MWCNTs）和氮化碳纳米片（CNNS）表面的活性基团，获得了含有共价键的 CNTs@CN 复合填料。具有双共价键的 CNTs@CN/PI 的导热系数可达 6.63 W m-1 K-1。填料与填料之间以及填料与基体之间的共价键为声子传输提供了高效、连续的途径。此外，有限元分析进一步揭示了 CNTs@CN/PI 复合薄膜的传热机制。因此，这将为增强 PI 的导热性提供一个可行的解决方案，使其在电子设备中的应用前景更加广阔。

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引用次数: 0