COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING
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2022
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IF 9.463
Qiangqiang Ma,Zhenyu Wang,Ting Liang,Yunpeng Su,Junhong Li,Yimin Yao,Xiangliang Zeng,Yunsong Pang,Meng Han,Xiaoliang Zeng,Jianbin Xu,Linlin Ren,Rong Sun
With heat-flux density of electronics drastically increase polymer-based thermal interface materials play a critical role in the performance of electronics. Although surface energy of fillers has been recognized as a crucial parameter, the exploitation of the filler surface energy-dependent properties is still unclear. Herein, we report on unveiling the effect of the surface energy of aluminum on thermal and mechanical properties in thermal interface materials consisted of polydimethylsiloxane and modified aluminum with silane-coupling agents containing varied chain lengths. The results show that reducing the surface energy of aluminum is beneficial to improve the aluminum fillers dispersibility in polydimethylsiloxane, leading to improved macroscopic properties, including rheology, mechanical properties, and thermal properties. Furthermore, based on the thermodynamic prediction, a winding hypothesis was proposed to explain the interaction between the modified aluminum and polydimethylsiloxane. This work provides valuable guidance for rationally designing the surface energy of fillers in thermal interface materials.
研究领域:
材料科学
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热管理技术
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产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
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2022
·Vol. 57
·期 10
·5788-5804
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IF 4.682
Niu Hao,Yang Dan-Lei,Pu Yuan,Wang Dan,Wang Jie-Xin
Nanocomposites have been used in various industries due to their excellent properties. For some of them, high filler content (over 50 wt%) is beneficial to improving their performances. This study aims to explore the network model construction and properties of high filler content dental resin composites (DRCs). An improved multistep dynamic cross-linking procedure was proposed and firstly applied to construct the reasonable molecular model of high filler content DRCs. The predicted elastic modulus and stress–strain results of DRCs with different nanofiller contents show that the DRCs with a 70 wt% filler content have the most excellent mechanical properties. Furthermore, the dynamic property study indicates that the diffusion coefficient of matrices firstly decreased and then increased with the nanofiller content increasing from 0 to 80 wt%, reaching the lowest value at 70 wt%. The migration of resin matrices can be limited by nanofillers at the content within 70 wt%. However, when the filler content is excessively high (80 wt%), the stability of matrices is destroyed and the fractional free volume of DRCs sharply increases, resulting in a decrease of mechanical properties of DRCs. The findings of this study deepen the understanding of structures and properties of DRCs at the atomic/molecular scales. Graphical Abstract
研究领域:
材料科学
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牙医学
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产品关联
DOI
高影响因子
COMPOSITES SCIENCE AND TECHNOLOGY
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2022
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IF 9.879
Zhuyu Ma,Kaiyi Zhang,Shengdu Yang,Yang Zhang,Xianchun Chen,Qiang Fu,Hua Deng
Capacitive sensors have vast application prospects. Their dielectric layer is hardened under high pressure, the sensitivity is reduced and sensing behavior is nonlinear. To tackle this, a novel strategy is used to incorporate voids, dielectric filler and conductive filler into the dielectric layer. Firstly, “root” like dendritic colloid polyurethane (DCPU) is prepared to grasp different content of carbon nanotube (CNT) and barium titanate (BaTiO 3 , BT), before such hybrid filler is coated onto the backbone of PU foam. For capacitive pressure sensors , it is observed that sensitivity increases with increasing filler content . More importantly, the addition of CNT into the inner layer of hybrid filler containing BT in the outer layer leads to linear pressure sensing behavior in a wide pressure range. Furthermore, the overall performance achieves a sensitivity of 2.51 kPa −1 under 0–100 kPa and a linearity of R 2 = 0.9989, and stable signals after 1000 cycles. Finally, it is successfully demonstrated that petals with a weight of 96 mg and the physiological signals of the human body such as heartbeat, swing arm amplitude, and joint bending can be detected. This work provides a new design inspiration for capacitive sensors with high sensitivity and high linearity in realizing medical health monitoring and motion detection.
研究领域:
材料科学
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传感器技术
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生物医学工程
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING RESEARCH & DESIGN
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2020
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IF 3.35
Yuan-Yuan Zhan,Yong Cai,Guang-Wen Chu,Yong Luo,Liang-Liang Zhang,Jian-Feng Chen
Spent caustic from the desulfurization of liquefied petroleum gas has been proved to be effectively regenerated in a rotating packed bed (RPB) with classic wire mesh packing. However, the influence of the packing’s surface wettability on regeneration performance in the RPB was not clear with this oil-water two-phase system. In this work, the surface-modified packing was proposed to be used in the RPB to estimate the regeneration performance, including oxidation and separation efficiency. Three different surface-modified packings of hydrophilic surface-modified wire mesh packing (ISP), non-surface-modified wire mesh packing (NSP), and hydrophobic surface-modified wire mesh packing (OSP) were prepared and employed in the RPB for regeneration experiments. Results show that regeneration performance is in order of ISP＞NSP＞OSP. Compared with OSP, the NaSR conversion, RSSR removal efficiency, and number of transfer units of ISP increased nearly by 34%, 13%, and 21% at 1000 r/min rotational speed and 25 mm packing thickness, respectively. For the view of different packing combination, not only in the inner layer but also in the outer layer, ISP had noticeable superior regeneration performance, which displays the bright future of advanced surface-modified packing used in the RPB for process intensification of reaction and separation.
研究领域:
化学工程
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环境工程
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DOI
高影响因子
DENTAL MATERIALS
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2021
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IF 5.304
Hao Niu,Dan-Lei Yang,Tianyu Gao,Jie-Xin Wang
Objective The purpose of this study is to develop a mathematical model for efficient prediction of the packing density of different filler formulations in dental resin composites (DRCs), and to study properties of DRCs at the maximum filler loading (MFL), thereby providing an effective guidance for the design of filler formulations in DRCs to obtain excellent properties. Methods The packing density data generated by discrete element model (DEM) simulation were used to re-derive the parameters of 3-parameter model. The modifier effect was also induced to modify the 3-parameter model. DRCs with 10 filler formulations were selected to test properties at the MFL. The packing densities of binary and ternary mixes in DRCs were calculated by 3-parameter model to explore the regularity of composite packing. Results The predicted packing density was validated by simulation and experimental results, and the prediction error is within 1.40 vol%. The optimization of filler compositions to obtain a higher packing density is beneficial to enhancing the mechanical properties and reducing the polymerization shrinkage of DRCs. In binary mixes, the maximum packing density occurs when the volume fraction of small fillers is 0.35−0.45, and becomes higher with the reduction of particle size ratio. In ternary mixes, the packing density can reach the maximum value when the volume fractions of large and small fillers are in the 0.5−0.75 and 0.15−0.4 ranges, respectively. Significance The modified 3-parameter model can provide an effective method to design the multi-level filler formulations of DRCs, thereby improving the performance of the materials.
研究领域:
牙科学
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材料科学
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
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2022
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IF 3.898
Zhiwei Wang,Yu Zhang,Zhi Zhang,Daowei Zhou,Zhikai Cao,Yong Sha
The catalytic packing is the core component of the catalytic distillation, and how the catalyst exists in the packing has significant influence on the process. To investigate the effect of catalyst packings on the catalytic distillation process, the classical ethyl acetate reactive distillation system was utilized, and a supported catalytic packing (SCP) was prepared in comparison with the conventional tea-bag catalytic packing (TBP). Laboratory scale experiments showed that the ethyl acetate conversion of the SCP was superior to the TBP at a low catalyst loading. The effects of reaction kinetics, mass transfer performance and actual catalytic efficiency of the packings on this process were regarded as reasons and studied by combining the experiments and numerical simulation. Results suggested that the relatively immediate “ in-situ separation” caused by the rapid reaction kinetics and better mass transfer performance of SCP may be a main reason for the difference of the conversion.
研究领域:
化学工程
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催化工艺
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产品关联
DOI
高影响因子
RUSSIAN JOURNAL OF APPLIED CHEMISTRY
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2021
·Vol. 94
·期 8
·1066-1071
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IF 0.85
Vorobyova E. V.
Abstract The effect of fillers, metal oxide nanoparticles (Fe 3 O 4 , ZnO), on the thermal oxidation resistance of polyethylene inhibited by the phenolic antioxidant Irganox 1010 was studied. The distribution of nanoparticles in the polymer matrix was carried out by ultrasound, and the samples were formed by thermal pressing. Thermal oxidation resistance was determined by the duration of the induction oxidation period of film samples. It is shown that the pressure of the press during the formation of the material has a significant effect on the thermal oxidation resistance of the inhibited composite, both filled with nanoparticles of Fe 3 O 4 , ZnO, and unfilled. The nature of the effect of the concentration of the nanofiller on the thermal oxidation resistance of the samples depends on the metal oxide used. An increase in the concentration of the filler Fe 3 O 4 leads to a decrease in the thermal oxidation resistance of the polymer; when using ZnO, this dependence is inverse. The oxidation of the prepared nanocomposite film samples formed under high pressure conditions revealed synergistic effects of nanofillers and antioxidants.
研究领域:
材料科学
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高分子化学
✓ 已验证
DOI
高影响因子
APPLIED THERMAL ENGINEERING
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2014
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IF 2.624
Yuan-Xiang Fu,Zhuo-Xian He,Dong-Chuan Mo,Shu-Shen Lu
Heat dissipation is an important issue for electronic devices. In the present work, we prepared eight kinds of thermal adhesives by filling the epoxy resin with natural graphite, copper, aluminum , zinc oxide , boron nitride , aluminum oxide, diamond and silver powders, and measured the thermal conductivity of all samples. The results show the eight fillers can efficiently improve the thermal conductivity of the epoxy resin. Meanwhile, we found the layer-shape filler is more favorable than the ball-shape filler and the sharp-corner-shape filler to enhance the thermal conductivity of epoxy resin, and the low price layer-shape natural graphite-epoxy adhesive had the highest thermal conductivity up to 1.68 W m −1 K −1 at weight 44.3% of the eight thermal adhesives. All the fillers and the cross sections of thermal adhesives morphologies images were characterized by scanning electron microscopy, and the thermal conductivities of all the samples were measured by Hot Disk TPS-2500 thermal constants analyzer.
研究领域:
材料科学
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热管理技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2015
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IF 2.999
Biao Zhang,Feng Ye,Shichao Liu,Haoqian Zhang,Qiang Liu,Ye Gao,Jie Ma
In this study, we developed a new route to fabricate polymer/ceramic composites. This method mainly involves tape casting and vacuum assist infiltration (called TC-VI). Composites, using Bisphenol-A cyanate ester resin (BADCy) as matrix and mixed dielectric ceramic powders (1− x ) Ni 0.5 Ti 0.5 NbO 4 + x ZnNb 2 O 6 ( x = 0–100 vol. %) as fillers, were prepared successfully by this route. Dielectric properties and thermal conductivity of the composites were tested. Furthermore, the migration of silver (Ag) electrodes in the composites was investigated. Results show that the composites exhibit excellent dielectric properties. Dielectric constant of the composites can be adjusted continuously from 13.49 to 22.46 (at 9045 MHz). Dielectric loss is lower than 3.68 × 10 −3 (at 7320 MHz). The addition of ceramic fillers can significantly enhance the thermal conductivity of BADCy resin. Moreover, no obvious Ag element migration can be detected in the composites. Due to the good performances of the composites, this method could be widely used in the fabrication of multilayer devices.
研究领域:
材料科学
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电子工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
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2025
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IF 3.9
Luo Yang,Guo Huangying,Wan Wenyu,Deng Pengcheng,Zhang Haiwei,Zhou Xing
With the development of information technology, electromagnetic pollution has become a new source of pollution. Efficient EMI shielding materials are urgently needed to deal with this problem, and conductivity is the key to achieving efficient shielding. Impedance mismatch makes the composite shielding material obtain electromagnetic wave reflection dissipation ability, but excessive reflection loss will lead to secondary pollution of the environment. In this paper, polyaniline-modified graphene nanosheets (GNS@PANI) were used as conductive fillers, and tin oxide-coated ferric oxide (Fe 3 O 4 @SnO 2 ) with a shell–core structure was added to self-healing polyurethane (PU) as a magnetic conductive filler. The magnetic nanofiller with high permeability was used to improve the absorbing ability of the composite shielding material. When the addition amount of Fe 3 O 4 @SnO 2 is only 7 wt%, the composite film exhibits a high tensile strength of 5.22 MPa and an ultra-high self-healing efficiency of 89.66%, and the maximum EMI SE can reach 29 dB. Meanwhile, the SE A in the EMI SE is as high as 17 dB, and the SE R is only 12 dB, which is much lower than the SE A . To further enhance the electromagnetic wave absorption loss, we prepared a “sandwich” structure layered fabric using layer-by-layer assembly technology. This composite film has excellent electromagnetic absorption loss ability and has broad application prospects in the fields of medical devices, communication networks and flexible wearable electronics. Graphical abstract
研究领域:
材料科学
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电磁兼容性
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纳米技术
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聚合物复合材料
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柔性电子
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
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2024
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IF 10.7
Miao Wang,Yijin He,Xiaoyu Yang,Xuhui Hou,Wenxuan Li,Shaobo Tan,Zhicheng Zhang
With the increasing demand for dielectric materials in high-frequency microwave applications, fluoropolymer-based dielectric materials have been widely utilized due to their excellent dielectric and insulation properties. However, the low thermal conductivity limits their ability to meet the thermal dissipation requirements during high-frequency and high-speed signal transmission. The present study introduces a pioneering interface engineering strategy wherein C–F bonds on the surface of ethylene-tetrafluoroethylene copolymer (ETFE) are photo-catalytically activated, enabling successful grafting of poly(glycidyl methacrylate) (PGMA) chain segments. Subsequently, the resulting graft copolymers are blended with thermally conductive h-BN filler to prepare composite dielectric materials. The results demonstrate that the incorporation of PGMA segments significantly enhances the interfacial compatibility between the ETFE matrix and h-BN filler, resulting in composites with a dense microstructure and outstanding dielectric and thermal properties. At a filler content of 30 vol%, the ETFE-g-PGMA@BN composite achieves an in-plane thermal conductivity of 4.2 W (m K)−1 and a through-plane thermal conductivity of 0.77 W (m K)−1. Moreover, at 1 GHz, the composite exhibits a dielectric constant of 2.2 and a dielectric loss of 0.004. This work presents a novel interface design strategy for surface modification of PTFE-based fluoropolymers, expanding their potential applications in printed circuit boards (PCBs) and providing a new direction for the design of polymer-based dielectric materials.
研究领域:
材料科学
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高分子化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
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2024
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IF 6.3
Li Liu,Tao Chen,Liping Han,Zhuo Qian,Junpeng Li,Guoyou Gan
The Thermal Conductive Silver Adhesive (TCSA) efficiently transfers heat from electronic components to heat dissipation components, preventing overheating and extending device lifespan. Despite the effectiveness of commercial sintered nano TCSA, high production costs necessitate a more affordable, high-performance preparation method. This study presents a strategy for preparing ultra-high thermal conductivity (TC) TCSA using multidimensional thermal conductive fillers and low-temperature sintering of silver nanoparticles (AgNPs). MXene@AgNPs particles are synthesized via in-situ reduction of AgNPs on MXene surfaces. These particles, combined with silver microflakes (AgMFs) as primary fillers and epoxy (EP), undergo low-temperature heat treatment to form the AgMFs-MXene@AgNPs/EP composite. Characterization and computational models show that filler-filler interface thermal resistance (ITR f-f ) is critical for TC. Adding MXene alone is insufficient, but using MXene@AgNPs particles as secondary fillers allows AgNPs to interconnect fillers, effectively reducing the ITR f-f . The resulting composite achieves an ultra-high TC of 65.51 Wm −1 K −1 with 63 wt% total filler content (60 wt% AgMFs, 3 wt% MXene@AgNPs). This study advances the development of low-cost, high-performance TCSA for thermal management applications.
研究领域:
材料科学
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热传导工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）