Pub Date : 2024-09-24DOI: 10.1016/j.compscitech.2024.110877
Yinfeng Liu , Tong Wang , Jing Wang , Xin Chen , Jianwen Chen , Zunfeng Liu , Yutian Zhu
Strain-insensitive conductive films as stretchable electromagnetic interference (EMI) shielding materials and stretchable electrodes are highly desired in wearable electronics. However, fabricating super strain-insensitive conductive films under a tensile strain higher than 400 % is still a great challenge. Herein, a super-stretchable conductive film based on the crumple-structured Ti3C2Tx nanosheets-single walled carbon nanotubes/stretchable substrate double-layers is designed for the stretchable EMI shielding materials and electrodes. The resulting film exhibits a strain-insensitive electrical conductivity as high as 3.01 × 103 S/m even at a strain up to 500 %, which endows the film with a high and stable electromagnetic interference shielding efficiency (EMI SE) value of ∼45 dB. More interestingly, the EMI SE value of the film remains nearly constant even after 2000 cycles of 500 % tensile strain, indicating the excellent long-term service stability as a stretchable EMI shielding material. Moreover, a capacitive strain sensor with extra-wide sensing range, ultra-high stability, and excellent durability is successfully achieved by employing the as-prepared films as stretchable electrodes. This work proposes a convenient strategy of strain-insensitive conductive film aiming to design stretchable EMI shielding materials and electrodes for wearable electronics.
{"title":"A super-stretchable conductive film with strain-insensitive conductivity for stretchable EMI shielding materials and wearable capacitive strain sensors","authors":"Yinfeng Liu , Tong Wang , Jing Wang , Xin Chen , Jianwen Chen , Zunfeng Liu , Yutian Zhu","doi":"10.1016/j.compscitech.2024.110877","DOIUrl":"10.1016/j.compscitech.2024.110877","url":null,"abstract":"<div><div>Strain-insensitive conductive films as stretchable electromagnetic interference (EMI) shielding materials and stretchable electrodes are highly desired in wearable electronics. However, fabricating super strain-insensitive conductive films under a tensile strain higher than 400 % is still a great challenge. Herein, a super-stretchable conductive film based on the crumple-structured Ti<sub>3</sub>C<sub>2</sub>T<sub>x</sub> nanosheets-single walled carbon nanotubes/stretchable substrate double-layers is designed for the stretchable EMI shielding materials and electrodes. The resulting film exhibits a strain-insensitive electrical conductivity as high as 3.01 × 10<sup>3</sup> S/m even at a strain up to 500 %, which endows the film with a high and stable electromagnetic interference shielding efficiency (EMI SE) value of ∼45 dB. More interestingly, the EMI SE value of the film remains nearly constant even after 2000 cycles of 500 % tensile strain, indicating the excellent long-term service stability as a stretchable EMI shielding material. Moreover, a capacitive strain sensor with extra-wide sensing range, ultra-high stability, and excellent durability is successfully achieved by employing the as-prepared films as stretchable electrodes. This work proposes a convenient strategy of strain-insensitive conductive film aiming to design stretchable EMI shielding materials and electrodes for wearable electronics.</div></div>","PeriodicalId":283,"journal":{"name":"Composites Science and Technology","volume":"258 ","pages":"Article 110877"},"PeriodicalIF":8.3,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142322290","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-23DOI: 10.1016/j.compscitech.2024.110880
Shiyu Li, Xuanxin Tian, Qiubo Li, Shigang Ai
Composite materials have been widely used as critical components in aerospace applications due to their excellent performance characteristics. The real-time accurate identification and quantification of various types of damage within composite material structures pose a significant challenge. This study introduces an innovative damage detection method based on strain fields, which centrally employs deep learning techniques. Utilizing the Res-Mask R–CNN, this study accurately detects and categorizes various forms of damage within composite laminates, including open holes, subsurface holes, and delamination. Moreover, this method also enables precise localization and quantification of damaged areas. A series of experiments and simulations have validated the accuracy and robustness of the network model. Damage inversion experiments demonstrate that the area error of the damaged regions has been reduced to 7.4 %, and the positional error does not exceed 3.31 mm. In simulated scenarios, the shape context distance for complex damage contours does not exceed 0.21, indicating that the critical geometric features of the damage have been successfully preserved. This study provides an effective new approach for damage detection and real-time structural health monitoring of composite laminates.
{"title":"Advancing structural health monitoring: Deep learning-enhanced quantitative analysis of damage in composite laminates using surface strain field","authors":"Shiyu Li, Xuanxin Tian, Qiubo Li, Shigang Ai","doi":"10.1016/j.compscitech.2024.110880","DOIUrl":"10.1016/j.compscitech.2024.110880","url":null,"abstract":"<div><div>Composite materials have been widely used as critical components in aerospace applications due to their excellent performance characteristics. The real-time accurate identification and quantification of various types of damage within composite material structures pose a significant challenge. This study introduces an innovative damage detection method based on strain fields, which centrally employs deep learning techniques. Utilizing the Res-Mask R–CNN, this study accurately detects and categorizes various forms of damage within composite laminates, including open holes, subsurface holes, and delamination. Moreover, this method also enables precise localization and quantification of damaged areas. A series of experiments and simulations have validated the accuracy and robustness of the network model. Damage inversion experiments demonstrate that the area error of the damaged regions has been reduced to 7.4 %, and the positional error does not exceed 3.31 mm. In simulated scenarios, the shape context distance for complex damage contours does not exceed 0.21, indicating that the critical geometric features of the damage have been successfully preserved. This study provides an effective new approach for damage detection and real-time structural health monitoring of composite laminates.</div></div>","PeriodicalId":283,"journal":{"name":"Composites Science and Technology","volume":"258 ","pages":"Article 110880"},"PeriodicalIF":8.3,"publicationDate":"2024-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142356988","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-23DOI: 10.1016/j.compscitech.2024.110879
Guojie Zhang, Junjie Peng, Hanbing Wang, Yi Lu, Yong Zhang
The recycling of zinc compound from waste tires and the negative impact of zinc oxide on environment have been major challenges in rubber industry. In this study, the components and microstructure of recovered carbon black (rCB) from waste tires pyrolysis are analyzed, in which the content of the ash and zinc element is 20 % and 6.1 %, and zinc sulfide is the main zinc compound. Zinc sulfide and zinc oxide could crosslink brominated butyl rubber (BIIR), and the crosslinking effect becomes more effective in the presence of carbon black N660. BIIR can be crosslinked and reinforced by rCB in the absence of other additives. BIIR/rCB composites have similar curing behavior and mechanical properties to the BIIR composites filled with N660 and cured by zine oxide. Therefore, rCB could replace commercial carbon black N660 and zinc oxide in BIIR, and this replacement will realize the effective use of carbon black and zinc compound in rCB from waste tires and promote the sustainable development of tire industry.
{"title":"Curing and reinforcement effect of recovered carbon black from waste tires on brominated butyl rubber","authors":"Guojie Zhang, Junjie Peng, Hanbing Wang, Yi Lu, Yong Zhang","doi":"10.1016/j.compscitech.2024.110879","DOIUrl":"10.1016/j.compscitech.2024.110879","url":null,"abstract":"<div><div>The recycling of zinc compound from waste tires and the negative impact of zinc oxide on environment have been major challenges in rubber industry. In this study, the components and microstructure of recovered carbon black (rCB) from waste tires pyrolysis are analyzed, in which the content of the ash and zinc element is 20 % and 6.1 %, and zinc sulfide is the main zinc compound. Zinc sulfide and zinc oxide could crosslink brominated butyl rubber (BIIR), and the crosslinking effect becomes more effective in the presence of carbon black N660. BIIR can be crosslinked and reinforced by rCB in the absence of other additives. BIIR/rCB composites have similar curing behavior and mechanical properties to the BIIR composites filled with N660 and cured by zine oxide. Therefore, rCB could replace commercial carbon black N660 and zinc oxide in BIIR, and this replacement will realize the effective use of carbon black and zinc compound in rCB from waste tires and promote the sustainable development of tire industry.</div></div>","PeriodicalId":283,"journal":{"name":"Composites Science and Technology","volume":"258 ","pages":"Article 110879"},"PeriodicalIF":8.3,"publicationDate":"2024-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142320295","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-23DOI: 10.1016/j.compscitech.2024.110882
Jing Chen , Nan Qin , Runlin Fan , Liming Jin , Junsheng Zheng , Pingwen Ming , Cunman Zhang , Jim P. Zheng
Composite bipolar plates (CBP) composed of resin and conductive filler are critical components in proton exchange membrane fuel cell (PEMFC) for achieving mechanical strength and electrical conductivity. The conductive filler entirely enveloped by resin is of significance for the flexibility of the CBP; while connected resin blocks the continued conductive channels and thus weakens the electrical properties of CBP. Herein, we propose a trade-off method between flexibility and conductivity of the CBP by wettability regulations of the resin, in which fumed silica additives are introduced into epoxy as composite adhesives. The abundant hydrogen bonds are demonstrated to be well-formed between epoxy and fumed silica for decreasing surface free energy (SFE) between resin and graphite. As a result, the composite adhesive with 2 % fumed silica delivers moderate wettability enabling much improved CBP, which exhibits high electrical conductivity of 233.33 S cm−1 as well as flexural strength of 66.4 MPa. Moreover, the CBP also delivers improved areal specific resistance (5.34 mΩ cm2), thermal conductivity (10.58 W (m K)−1), and corrosion behaviors (0.0701 A cm−2) which guarantee the operation of the PEMFC. This work provides new insight from the wettability regulation of resins for improved CBP, which is an easy-operating method and has great potential for application in practical CBP fabrication.
{"title":"Fumed silica additives enables tunable wettability of the resin for improved composite bipolar plate","authors":"Jing Chen , Nan Qin , Runlin Fan , Liming Jin , Junsheng Zheng , Pingwen Ming , Cunman Zhang , Jim P. Zheng","doi":"10.1016/j.compscitech.2024.110882","DOIUrl":"10.1016/j.compscitech.2024.110882","url":null,"abstract":"<div><div>Composite bipolar plates (CBP) composed of resin and conductive filler are critical components in proton exchange membrane fuel cell (PEMFC) for achieving mechanical strength and electrical conductivity. The conductive filler entirely enveloped by resin is of significance for the flexibility of the CBP; while connected resin blocks the continued conductive channels and thus weakens the electrical properties of CBP. Herein, we propose a trade-off method between flexibility and conductivity of the CBP by wettability regulations of the resin, in which fumed silica additives are introduced into epoxy as composite adhesives. The abundant hydrogen bonds are demonstrated to be well-formed between epoxy and fumed silica for decreasing surface free energy (SFE) between resin and graphite. As a result, the composite adhesive with 2 % fumed silica delivers moderate wettability enabling much improved CBP, which exhibits high electrical conductivity of 233.33 S cm<sup>−1</sup> as well as flexural strength of 66.4 MPa. Moreover, the CBP also delivers improved areal specific resistance (5.34 mΩ cm<sup>2</sup>), thermal conductivity (10.58 W (m K)<sup>−1</sup>), and corrosion behaviors (0.0701 A cm<sup>−2</sup>) which guarantee the operation of the PEMFC. This work provides new insight from the wettability regulation of resins for improved CBP, which is an easy-operating method and has great potential for application in practical CBP fabrication.</div></div>","PeriodicalId":283,"journal":{"name":"Composites Science and Technology","volume":"258 ","pages":"Article 110882"},"PeriodicalIF":8.3,"publicationDate":"2024-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142322289","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-23DOI: 10.1016/j.compscitech.2024.110883
Hao Zhang , Xiaoyu Ding , Yongjie Yang , Qinfu Liu , Leibo Ji , Kuo Li , Junmin Sun , Zhiming Sun , Qianyi Ma , Ying Wu , Xinyang Liu , Chul B. Park , Naisheng Jiang
This study investigated the structural evolution of synthetic coal-derived graphite (SCG), produced from anthracite through high-temperature treatments ranging from 1000 to 2900 °C, and its reinforcement potential in styrene butadiene rubber (SBR) composites. Upon heating the anthracite to 2000 °C, We observed a gradual structural transformation from an amorphous carbon structure with mixed sp2-sp3 bonding to an ordered sp2-bonded nano-sized graphitic structure. This transformation was accompanied by the evaporation of heteroatom functional groups, an increase in high surface energy site as well as micropore and void structures, and enhanced hydrophobic surface property. Beyond 2000 °C, a flake-like graphite with a larger particle size (average lateral size >10 μm) was gradually formed through lateral and vertical crystalline growth mechanisms. The reinforcing potential of SCG fillers was revealed by incorporating them into SBR and evaluating the properties of the resulting composites. It was found that the tensile strength and 300 % tensile modulus initially enhanced with SCG fillers treated up to 2000 °C, but decreased for fillers treated at 2300 and 2900 °C. On the other hand, storage modulus, tear resistance, and gas permeability consistently improved with fillers treated at higher temperatures. These findings highlight the relationship between the temperature-induced structural evolution of SCG fillers and their reinforcement performance in SBR composites, offering valuable insights for industrial rubber applications, particularly enhancing the performance and sustainability of automotive tire.
{"title":"Temperature-dependent evolution of synthetic coal-derived graphite fillers and their reinforcement in styrene butadiene rubber composites","authors":"Hao Zhang , Xiaoyu Ding , Yongjie Yang , Qinfu Liu , Leibo Ji , Kuo Li , Junmin Sun , Zhiming Sun , Qianyi Ma , Ying Wu , Xinyang Liu , Chul B. Park , Naisheng Jiang","doi":"10.1016/j.compscitech.2024.110883","DOIUrl":"10.1016/j.compscitech.2024.110883","url":null,"abstract":"<div><div>This study investigated the structural evolution of synthetic coal-derived graphite (SCG), produced from anthracite through high-temperature treatments ranging from 1000 to 2900 °C, and its reinforcement potential in styrene butadiene rubber (SBR) composites. Upon heating the anthracite to 2000 °C, We observed a gradual structural transformation from an amorphous carbon structure with mixed <em>sp</em><sup><em>2</em></sup>-<em>sp</em><sup><em>3</em></sup> bonding to an ordered <em>sp</em><sup><em>2</em></sup>-bonded nano-sized graphitic structure. This transformation was accompanied by the evaporation of heteroatom functional groups, an increase in high surface energy site as well as micropore and void structures, and enhanced hydrophobic surface property. Beyond 2000 °C, a flake-like graphite with a larger particle size (average lateral size >10 μm) was gradually formed through lateral and vertical crystalline growth mechanisms. The reinforcing potential of SCG fillers was revealed by incorporating them into SBR and evaluating the properties of the resulting composites. It was found that the tensile strength and 300 % tensile modulus initially enhanced with SCG fillers treated up to 2000 °C, but decreased for fillers treated at 2300 and 2900 °C. On the other hand, storage modulus, tear resistance, and gas permeability consistently improved with fillers treated at higher temperatures. These findings highlight the relationship between the temperature-induced structural evolution of SCG fillers and their reinforcement performance in SBR composites, offering valuable insights for industrial rubber applications, particularly enhancing the performance and sustainability of automotive tire.</div></div>","PeriodicalId":283,"journal":{"name":"Composites Science and Technology","volume":"258 ","pages":"Article 110883"},"PeriodicalIF":8.3,"publicationDate":"2024-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142417681","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-21DOI: 10.1016/j.compscitech.2024.110875
Ping Wang , Caiqing Mo , Yanqing Liu , Ying Jiang , Zhicheng Zhang , Huajun Wu , Guiyu Luo , Yu She , En-Tang Kang , Kai Zhang , Liqun Xu
If not removed in a timely manner, the large amount of sweat produced by overheated human skin can cause thermal discomfort and health problems. Development of fabrics with cooling and dehumidifying capabilities is advantageous to improving the quality of human life. In this work, a natural leather-based Zn-monoethanolamine@lignin (Zn-MEA@lignin-leather) composite fabric with personal hygrothermal management properties was fabricated by infiltrating the permeable 3D network microstructure of the natural leather collagen fiber bundles with adhering moisture-absorbent hydrogel containing photothermal lignin. Due to the efficiency of the composite hydrogel in trapping water molecules, the fabric can promote evaporation of sweat from overheated skin surfaces. Compared to the conventional textiles, the composite leather fabric can reduce the humidity of simulated skin surface by about 40 % and accelerate the evaporation of sweat from the skin surface to promote reduction in temperature of the overheated body. Thanks to the good photothermal conversion efficiency of lignin, the hydrated composite fabric exhibits a favorable evaporation regeneration rate (0.498 kg m−2 h−1). In addition, the presence of zinc ions in the coordination complex imparts good antimicrobial efficiency to the composite fabric, with inactivation rates approaching 99.99 % for both Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). Thus, the composite leather fabric holds great promise to personal hygrothermal management and healthcare.
人体皮肤过热产生的大量汗液如不及时排出，会引起热不适和健康问题。开发具有降温和除湿功能的织物有利于提高人类的生活质量。在这项研究中，通过在天然皮革胶原纤维束的渗透性三维网络微结构中渗入含有光热木质素的吸湿水凝胶，制备了一种具有个人湿热管理特性的天然皮革基 Zn- 单乙醇胺@木质素（Zn-MEA@木质素-皮革）复合织物。由于复合水凝胶能有效吸附水分子，因此织物能促进过热皮肤表面的汗液蒸发。与传统纺织品相比，复合皮革织物可将模拟皮肤表面的湿度降低约 40%，并加速皮肤表面汗液的蒸发，从而促进过热体温的降低。由于木质素具有良好的光热转换效率，水合复合织物显示出良好的蒸发再生率（0.498 kg m-2 h-1）。此外，配位复合物中锌离子的存在为复合织物带来了良好的抗菌效率，对金黄色葡萄球菌（S. aureus）和大肠杆菌（E. coli）的灭活率接近 99.99%。因此，复合皮革织物在个人温湿度管理和医疗保健方面大有可为。
{"title":"A multifunctional leather composite with good antibacterial and hygrothermal management capabilities","authors":"Ping Wang , Caiqing Mo , Yanqing Liu , Ying Jiang , Zhicheng Zhang , Huajun Wu , Guiyu Luo , Yu She , En-Tang Kang , Kai Zhang , Liqun Xu","doi":"10.1016/j.compscitech.2024.110875","DOIUrl":"10.1016/j.compscitech.2024.110875","url":null,"abstract":"<div><div>If not removed in a timely manner, the large amount of sweat produced by overheated human skin can cause thermal discomfort and health problems. Development of fabrics with cooling and dehumidifying capabilities is advantageous to improving the quality of human life. In this work, a natural leather-based Zn-monoethanolamine@lignin (Zn-MEA@lignin-leather) composite fabric with personal hygrothermal management properties was fabricated by infiltrating the permeable 3D network microstructure of the natural leather collagen fiber bundles with adhering moisture-absorbent hydrogel containing photothermal lignin. Due to the efficiency of the composite hydrogel in trapping water molecules, the fabric can promote evaporation of sweat from overheated skin surfaces. Compared to the conventional textiles, the composite leather fabric can reduce the humidity of simulated skin surface by about 40 % and accelerate the evaporation of sweat from the skin surface to promote reduction in temperature of the overheated body. Thanks to the good photothermal conversion efficiency of lignin, the hydrated composite fabric exhibits a favorable evaporation regeneration rate (0.498 kg m<sup>−2</sup> h<sup>−1</sup>). In addition, the presence of zinc ions in the coordination complex imparts good antimicrobial efficiency to the composite fabric, with inactivation rates approaching 99.99 % for both <em>Staphylococcus aureus</em> (<em>S. aureus</em>) and <em>Escherichia coli</em> (<em>E. coli</em>). Thus, the composite leather fabric holds great promise to personal hygrothermal management and healthcare.</div></div>","PeriodicalId":283,"journal":{"name":"Composites Science and Technology","volume":"258 ","pages":"Article 110875"},"PeriodicalIF":8.3,"publicationDate":"2024-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142320293","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-21DOI: 10.1016/j.compscitech.2024.110869
Jiangang Zhou, Congzhen Xie, Huasong Xu, Bin Gou, An Zhong, Daoming Zhang, Hangchuan Cai, Chunhui Bi, Licheng Li, Rui Wang
The lagging development of thermally conductive but electrically insulating materials has become a bottleneck problem for the next generation of advanced high-power density electronic devices. Although second-phase reinforced composites are promising materials for addressing thermal management issues, the inherent mechanism of severe phonon scattering at the interphase results in actual thermal conductivity enhancement efficiency far below expectations. Here, we report a high-performance polymer composite with a nest-like interconnected boron nitride skeleton. This nest-like interconnected BN skeleton without mechanical contact can provide high-efficiency and long-distance phonon transport channel, realizing high thermal conductivity of 1.827 W m−1 K−1 in polymer composite with ultra-low content (4.7 vol%). Meanwhile, the EP/nest-like BS composites possess ideal electrical properties and dimensional stability. In the actual heat dissipation process of LED chips, the optimal composite material as the thermal interface material can display a temperature drop of more than 34.8 % compared to neat epoxy, which proves the broad application prospects of this strategy in advanced electronic devices.
导热但绝缘材料的发展滞后已成为下一代先进高功率密度电子设备的瓶颈问题。尽管第二相增强复合材料是解决热管理问题的有前途的材料，但由于相间存在严重的声子散射，其固有机制导致实际热导增强效率远低于预期。在此，我们报告了一种具有巢状互连氮化硼骨架的高性能聚合物复合材料。这种无机械接触的巢状互连氮化硼骨架可提供高效的长距离声子传输通道，在超低含量（4.7 vol%）的聚合物复合材料中实现了 1.827 W m-1 K-1 的高热导率。同时，EP/nest-like BS 复合材料具有理想的电气性能和尺寸稳定性。在 LED 芯片的实际散热过程中，作为热界面材料的最佳复合材料与纯环氧树脂相比，温度下降超过 34.8%，这证明了该策略在先进电子设备中的广阔应用前景。
{"title":"Self-assembled nest-like BN skeletons enable polymer composites with high thermal management capacity","authors":"Jiangang Zhou, Congzhen Xie, Huasong Xu, Bin Gou, An Zhong, Daoming Zhang, Hangchuan Cai, Chunhui Bi, Licheng Li, Rui Wang","doi":"10.1016/j.compscitech.2024.110869","DOIUrl":"10.1016/j.compscitech.2024.110869","url":null,"abstract":"<div><div>The lagging development of thermally conductive but electrically insulating materials has become a bottleneck problem for the next generation of advanced high-power density electronic devices. Although second-phase reinforced composites are promising materials for addressing thermal management issues, the inherent mechanism of severe phonon scattering at the interphase results in actual thermal conductivity enhancement efficiency far below expectations. Here, we report a high-performance polymer composite with a nest-like interconnected boron nitride skeleton. This nest-like interconnected BN skeleton without mechanical contact can provide high-efficiency and long-distance phonon transport channel, realizing high thermal conductivity of 1.827 W m<sup>−1</sup> K<sup>−1</sup> in polymer composite with ultra-low content (4.7 vol%). Meanwhile, the EP/nest-like BS composites possess ideal electrical properties and dimensional stability. In the actual heat dissipation process of LED chips, the optimal composite material as the thermal interface material can display a temperature drop of more than 34.8 % compared to neat epoxy, which proves the broad application prospects of this strategy in advanced electronic devices.</div></div>","PeriodicalId":283,"journal":{"name":"Composites Science and Technology","volume":"258 ","pages":"Article 110869"},"PeriodicalIF":8.3,"publicationDate":"2024-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142310721","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-21DOI: 10.1016/j.compscitech.2024.110874
Tian Yang , Qing Qi , Li Ma , Tian Li , Jiatong Li , Qian Yang , Fanbin Meng
A novel strategy has been developed for preparing porous carbon materials derived from taro stems, aimed at enhancing electromagnetic wave (EMW) attenuation and thermal energy storage. The materials were synthesized through the carbonization of taro stems to form a porous carbon structure, subsequently enhanced with polyethylene glycol (PEG) containing carbon nanotubes (CNTs) and nickel (Ni) nanoparticles. By adjusting the carbonization temperature and the loading of CNTs and Ni, the resulting carbon materials exhibited exceptional EMW attenuation performance. Specifically, the PC-800 sample demonstrated a remarkable minimum reflection loss of −61.4 dB across the frequency range of 8.2–11 GHz, with a low density of 0.054 g/cm³. The PC-1200 sample exhibited EMI SE values of 23.6 dB axially and 21.5 dB radially in the X-band, with an ultra-low density of 0.033 g/cm³. Further enhancements were observed in the PC/CNT2 and PC/CNT2-Ni15 composites, achieving EMI SE values of 26.3 dB and 26.8 dB, respectively. Additionally, these composites exhibited effective thermal energy storage and release, as confirmed by heating experiments. This study not only introduces a method for creating absorption-dominated biomass electromagnetic shielding materials but also provides a dual-functional solution for enhancing the performance of electronic devices.
研究人员开发了一种新型战略，用于制备从芋头茎中提取的多孔碳材料，旨在增强电磁波（EMW）衰减和热能存储。这种材料是通过碳化芋头茎形成多孔碳结构，然后用含有碳纳米管（CNTs）和镍（Ni）纳米颗粒的聚乙二醇（PEG）进行增强而合成的。通过调整碳化温度以及碳纳米管和镍的负载量，所得到的碳材料表现出卓越的电磁波衰减性能。具体来说，PC-800 样品在 8.2-11 GHz 频率范围内的最小反射损耗为 -61.4 dB，密度低至 0.054 g/cm³。PC-1200 样品在 X 波段的轴向 EMI SE 值为 23.6 dB，径向 EMI SE 值为 21.5 dB，密度超低，仅为 0.033 g/cm³。PC/CNT2 和 PC/CNT2-Ni15 复合材料的 EMI SE 值进一步提高，分别达到 26.3 dB 和 26.8 dB。此外，这些复合材料还表现出有效的热能存储和释放，这一点已通过加热实验得到证实。这项研究不仅介绍了一种制造以吸收为主的生物质电磁屏蔽材料的方法，还为提高电子设备的性能提供了一种双功能解决方案。
{"title":"Lightweight composites derived from carbonized taro stems for microwave energy attenuation and thermal energy storage","authors":"Tian Yang , Qing Qi , Li Ma , Tian Li , Jiatong Li , Qian Yang , Fanbin Meng","doi":"10.1016/j.compscitech.2024.110874","DOIUrl":"10.1016/j.compscitech.2024.110874","url":null,"abstract":"<div><div>A novel strategy has been developed for preparing porous carbon materials derived from taro stems, aimed at enhancing electromagnetic wave (EMW) attenuation and thermal energy storage. The materials were synthesized through the carbonization of taro stems to form a porous carbon structure, subsequently enhanced with polyethylene glycol (PEG) containing carbon nanotubes (CNTs) and nickel (Ni) nanoparticles. By adjusting the carbonization temperature and the loading of CNTs and Ni, the resulting carbon materials exhibited exceptional EMW attenuation performance. Specifically, the PC-800 sample demonstrated a remarkable minimum reflection loss of −61.4 dB across the frequency range of 8.2–11 GHz, with a low density of 0.054 g/cm³. The PC-1200 sample exhibited EMI SE values of 23.6 dB axially and 21.5 dB radially in the X-band, with an ultra-low density of 0.033 g/cm³. Further enhancements were observed in the PC/CNT2 and PC/CNT2-Ni15 composites, achieving EMI SE values of 26.3 dB and 26.8 dB, respectively. Additionally, these composites exhibited effective thermal energy storage and release, as confirmed by heating experiments. This study not only introduces a method for creating absorption-dominated biomass electromagnetic shielding materials but also provides a dual-functional solution for enhancing the performance of electronic devices.</div></div>","PeriodicalId":283,"journal":{"name":"Composites Science and Technology","volume":"258 ","pages":"Article 110874"},"PeriodicalIF":8.3,"publicationDate":"2024-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142310723","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Deployable components and structures are a crucial part of space exploration. Due to fewer parts, low weight and cost, shape memory polymers (SMPs) and their composites (SMPCs) are considered ideal candidates for this. However, lower thermal stability and poor durability in the space environment have limited their applicability. This research work details the development of Graphene Nanoplatelets (GNP) filled Glass Fibre (GF) reinforced cyanate ester-based SMPC with 0/90° and ±45° sandwich fibre lay-up configuration capable of multidirectional shape programming. The SMP matrix was synthesised by mixing Cyanate Ester and Polyethylene Glycol (PEG) with added GNP. SMPC was fabricated by pouring the SMP mixture into a pre-prepared glass mould with the added GF layers. The synthesised SMPC showed shape programming and recovery at 169.01 ± 0.62 °C and stable thermomechanical properties at the temperature of 130 °C. Durability tests at extreme environmental conditions including Atomic Oxygen exposure, thermal vacuum aging, and elevated-temperature behaviour tests were conducted as these tests evaluate the durability and applicability of the SMPC for use in Earth's orbits and lunar environments. The performances of the samples before and after durability tests were measured through mechanical tests, shape memory effect tests and a series of characterisation methods such as microscopic image analysis, FTIR and dynamic mechanical analysis. According to the results, AO exposure affected the SMPCs by eroding their surface. There were no changes in the chemical structure of the SMPC yet the thermomechanical, mechanical and shape memory properties were decreased without compromising their safe operational levels such as storage onset temperatures (128.79 ± 3.08 °C), maximum tensile stress (114.99 ± 21.52 MPa), shape fixity (100 %) and recovery ratios (100 %). The erosion resistance of the GNP-filled SMPCs was improved with ∼54.35 % less erosion than the SMPC without GNP. The vacuum thermal aging slightly slowed shape recovery from 31.17 % to 8.32 % at 160 °C due to PEG crosslink degradation, however, 100 % shape recovery was achieved at the end. Further durability tests under cryogenic temperatures and effects after vacuum thermal cycles are warranted to observe the synergistic effect on the SMPC for future developments. Exploring the scalability and additive manufacturability of the developed SMPC can be advantageous in the future while mitigating challenges such as complex shape programming, long-term materials degradation, resource efficiency and compliance with safety standards.
{"title":"Effect of atomic oxygen and vacuum thermal aging on graphene and glass fibre reinforced cyanate ester-based shape memory polymer composite for deployable thin wall structures","authors":"Sandaruwan Jayalath , Eduardo Trifoni , Jayantha Epaarachchi , Madhubhashitha Herath , Eleftherios E. Gdoutos , Bandu Samarasekara","doi":"10.1016/j.compscitech.2024.110870","DOIUrl":"10.1016/j.compscitech.2024.110870","url":null,"abstract":"<div><div>Deployable components and structures are a crucial part of space exploration. Due to fewer parts, low weight and cost, shape memory polymers (SMPs) and their composites (SMPCs) are considered ideal candidates for this. However, lower thermal stability and poor durability in the space environment have limited their applicability. This research work details the development of Graphene Nanoplatelets (GNP) filled Glass Fibre (GF) reinforced cyanate ester-based SMPC with 0/90° and ±45° sandwich fibre lay-up configuration capable of multidirectional shape programming. The SMP matrix was synthesised by mixing Cyanate Ester and Polyethylene Glycol (PEG) with added GNP. SMPC was fabricated by pouring the SMP mixture into a pre-prepared glass mould with the added GF layers. The synthesised SMPC showed shape programming and recovery at 169.01 ± 0.62 °C and stable thermomechanical properties at the temperature of 130 °C. Durability tests at extreme environmental conditions including Atomic Oxygen exposure, thermal vacuum aging, and elevated-temperature behaviour tests were conducted as these tests evaluate the durability and applicability of the SMPC for use in Earth's orbits and lunar environments. The performances of the samples before and after durability tests were measured through mechanical tests, shape memory effect tests and a series of characterisation methods such as microscopic image analysis, FTIR and dynamic mechanical analysis. According to the results, AO exposure affected the SMPCs by eroding their surface. There were no changes in the chemical structure of the SMPC yet the thermomechanical, mechanical and shape memory properties were decreased without compromising their safe operational levels such as storage onset temperatures (128.79 ± 3.08 °C), maximum tensile stress (114.99 ± 21.52 MPa), shape fixity (100 %) and recovery ratios (100 %). The erosion resistance of the GNP-filled SMPCs was improved with ∼54.35 % less erosion than the SMPC without GNP. The vacuum thermal aging slightly slowed shape recovery from 31.17 % to 8.32 % at 160 °C due to PEG crosslink degradation, however, 100 % shape recovery was achieved at the end. Further durability tests under cryogenic temperatures and effects after vacuum thermal cycles are warranted to observe the synergistic effect on the SMPC for future developments. Exploring the scalability and additive manufacturability of the developed SMPC can be advantageous in the future while mitigating challenges such as complex shape programming, long-term materials degradation, resource efficiency and compliance with safety standards.</div></div>","PeriodicalId":283,"journal":{"name":"Composites Science and Technology","volume":"258 ","pages":"Article 110870"},"PeriodicalIF":8.3,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0266353824004408/pdfft?md5=cf157681a76f26bb6a51b08259c2e02e&pid=1-s2.0-S0266353824004408-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142310717","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
High-energy laser is widely used for machining carbon fiber reinforced polymer (CFRP) composites because of their high precision and fine quality. However, the mechanism by which CFRPs are damaged by high-energy laser in processing is unclear. In this article, the coupled mechanism of laser-ablated CFRPs is investigated experimentally and theoretically. The three-dimensional morphology of laser-damaged CFRPs is captured by computed tomography (CT), which quantitatively characterizes the degree of pyrolytic charring and internal delamination. Accordingly, a thermal-mechanical-chemical coupled model is established considering the matrix pyrolysis, pyrolysis gases flow, sublimation of the charring layer and mechanical failure. The progressive loss of solid media and the inhomogeneous deformation of CFRPs are incorporated into the traditional ablation kinetic model, making it possible to describe the damage to CFRPs caused by both chemical reactions and thermal stress. The predicted damage morphology is consistent with the experimental results, revealing the generation of internal defects due to the synergistic effects of interlaminar tensile stress and matrix pyrolysis. Additionally, the effects of charring layer sublimation, laser power and process time on damage responses are analyzed, and the real-time evolution of damage degree is investigated.
{"title":"Thermal-mechanical-chemical coupled model and three-dimensional damage evaluation based on computed tomography for high-energy laser-ablated CFRP","authors":"Yaoran Li, Jiawei Chen, Shengyu Duan, Panding Wang, Hongshuai Lei, Zeang Zhao, Daining Fang","doi":"10.1016/j.compscitech.2024.110867","DOIUrl":"10.1016/j.compscitech.2024.110867","url":null,"abstract":"<div><div>High-energy laser is widely used for machining carbon fiber reinforced polymer (CFRP) composites because of their high precision and fine quality. However, the mechanism by which CFRPs are damaged by high-energy laser in processing is unclear. In this article, the coupled mechanism of laser-ablated CFRPs is investigated experimentally and theoretically. The three-dimensional morphology of laser-damaged CFRPs is captured by computed tomography (CT), which quantitatively characterizes the degree of pyrolytic charring and internal delamination. Accordingly, a thermal-mechanical-chemical coupled model is established considering the matrix pyrolysis, pyrolysis gases flow, sublimation of the charring layer and mechanical failure. The progressive loss of solid media and the inhomogeneous deformation of CFRPs are incorporated into the traditional ablation kinetic model, making it possible to describe the damage to CFRPs caused by both chemical reactions and thermal stress. The predicted damage morphology is consistent with the experimental results, revealing the generation of internal defects due to the synergistic effects of interlaminar tensile stress and matrix pyrolysis. Additionally, the effects of charring layer sublimation, laser power and process time on damage responses are analyzed, and the real-time evolution of damage degree is investigated.</div></div>","PeriodicalId":283,"journal":{"name":"Composites Science and Technology","volume":"258 ","pages":"Article 110867"},"PeriodicalIF":8.3,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142315742","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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