EUROPEAN POLYMER JOURNAL
·
2023
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IF 6
Hong Li,Feng Bao,Xiaoqian Lan,Shuanger Li,Haoran Zhu,Yadong Li,Mingliang Wang,Caizhen Zhu,Jian Xu
With the rapid development of 5G communications, the traditional interlayer dielectric material polyimide (PI) requires modification due to its intrinsically high dielectric constant (D k ), high dielectric loss (D f ), and high moisture absorption, which make it difficult to meet the needs of the high-frequency communications industry. In this paper, a new strategy for the preparation of novel PI with intrinsically low D k and D f is proposed from the perspective of molecular structure design, the modification effect of superimposing bulky triphenyl pyridine structures and strong electronegativity groups, combined with long-chain anhydride to reduce the density of the imide structure. Therefore, three bulk diamine monomers (BPAB, PBAB3F, PBAB6F) containing triphenyl pyridine structures were designed in this paper and polymerized with 4,4′-(4,4′-isopropyldiphenoxy) phthalic anhydride (BPADA) to obtain three new PIs (PI-H, PI-CF 3 , PI-2CF 3 ) with different fluorine contents, focusing on the relationship between structure and properties, especially the effect of fluorine content on dielectric properties . The results of the study show that the dielectric and hygroscopic properties of PI improve with increasing fluorine content. Among them, PI-2CF 3 has the best overall performance, showing low dielectric (D k = 2.72@10 GHz & D f = 0.00233@10 GHz), high transparency (Cut-off wavelength (λ 0 ) = 389 nm, Maximum transmittance (T via ) = 89%) and low hygroscopicity (Water absorption (M a ) = 0.246%, Contact angle (C a ) = 111°).
研究领域:
材料科学
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电子工程
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DOI
高影响因子
INORGANIC CHEMISTRY
·
2024
·
IF 4.3
Tingting Tang,Fangqing Ye,Huang Hua,Chaoyang Li,Jian Shen
With the rapid development of 5G communication technology, microwave dielectric ceramics with high dielectric constants are very conducive to the miniaturization of passive devices. Here, Ba3Ti4–x(Ni1/3Nb2/3)xNb4O21 (BTN ∼ NN, 0.03 ≤ x ≤ 0.15) ceramics with hexagonal phases are synthesized via the solid-phase route. The composite (Ni1/3Nb2/3)4+ ion substitution strategy can substantially improve the microwave dielectric properties of the Ba3Ti4Nb4O21 (BTN) ceramic. The εr and Q × f values depend on the ionicity (Nb–O bonds) and lattice energies (Nb(1)–O3 and Nb(1)–O2(1) bonds). The microwave dielectric properties of the BTN ∼ NN (x = 0.09) ceramic sintered at 1250 °C are εr = 60.3, Q × f = 22073 GHz, and τf = 78.1 ppm/°C. A miniaturized all-ceramic radome (@400 mm × 400 mm × 8 mm) for 5G beam-splitting function is designed and demonstrated using this ceramic. Compared to other radomes designed for other work utilizing low εr, the size of this radome has been reduced by 3/7. The reflection coefficients of the beam splitting function are all 0.73, and the phase shifts are all 360°. This work contributes to the development of miniaturized passive devices from a materials point of view.
研究领域:
材料科学
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电子工程
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DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Baolin Guo,Xiaokang Li,Yiwen Wu,Qing Yao
Microwave dielectric ceramics, as a novel electronic material, had been extensively utilized in the fabrication of radio frequency components for communication systems, including filters, dielectric antennas, and radar applications. While dry pressing remained the most prevalent method for filter fabrication, this study proposed an innovative gel casting system for manufacturing ceramic waveguide filters. The developed system employed Hydantion epoxy resin (HER) as the gelling agent, polyethyleneimine (PEI) as the curing agent, and MgTiO 3 -CaTiO 3 (MCT) ceramic powder (exhibiting dielectric properties of ε r = 20.5, Q×f = 55,000 GHz, and τ f = ±10 ppm/°C) as the dielectric material. Experimental results demonstrated that incorporating 13 wt.% Hydantoin epoxy resin with 0.7 wt.% polyacrylic acid (PAA) dispersant yields a well-dispersed ceramic slurry containing 80 wt.% solid loading. After drying, the green body was sintered at 1400 °C for 3 h at air atmosphere. This process resulted in densified samples with homogeneous microstructure and optimized microwave dielectric properties. Building upon this foundation, a fourth-order waveguide filter was designed and fabricated with a center frequency of 3.5 GHz, bandwidth of 300 MHz, and return loss exceeding 15 dB. Compared to conventional dry pressing techniques, the gel casting approach demonstrated distinct advantages in simplified processing and cost-effectiveness. Its superior near-net-shape forming capability for complex geometries proved potential applications in next-generation 5G/6G microwave devices.
研究领域:
材料科学
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电气工程
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微波技术
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通信系统
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陶瓷工艺
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DOI
高影响因子
POLYMER COMPOSITES
·
2024
·
IF 4.8
Lingyuan Liao,Wenhong Ruan,Mingqiu Zhang,Weihao Li,Musong Lin
Incorporation of boron nitride (BN) into polymers is a promising method to obtain composites with high thermal conductivity, low dielectric constant ( D k ), and dielectric loss ( D f ), while the practical applications are limited by the poor interface between BN and polymer because of surface energy mismatch and absence of covalent bond connection between them. Herein, polydopamine (PDA) with good adhesion is deposited onto the BN. Then, a different amount of silane coupling agent containing vinyl reactive groups is grafted onto PDA-coated BN. In this way, the surface energy of modified BN (m-BN) can be adjusted to ensure BN contacts well with polymers. Moreover, reactive groups were introduced on BN for further reaction. Subsequently, covalent bonds between the m-BN and the polyphenylene oxide (PPO) were established in situ during the curing process. The effects of the m-BN surface energy on interface quality and thermal conductivity of composites are investigated. The m-BN/PPO composite achieves a through-plane thermal conductivity of 5.87 W/m · K and a low D f value of 1.53 × 10 −3 , as well as a low coefficient of thermal expansion (CTE) value (7.8 ppm/K) when the m-BN loading is 32.6 vol%. This research provides a simple and efficient strategy for fabricating high-performance composites for high-frequency applications. Highlights Hexagonal boron nitride was modified successfully by combining non-covalent and covalent modifications. Regulating surface energy and establishing covalent bonds enhances interface interaction between BN and polyphenylene oxide. Modified BN/polyphenylene oxide composites display improvements in thermal conductivity and dimensional stability as well as dielectric loss. Provides a feasible strategy for designing polymer composites with high thermal conductivity, dimensional stability, and low dielectric loss for 5G applications.
研究领域:
材料科学
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高分子化学
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电子材料
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产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
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2025
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IF 2.8
Ying Lei,Jianyang Zhang,Haoquan Zhuang,Tao Yin,Pengcheng Lin
High-power consumption causes excessive heat of 5G devices, compromising performance and lifespan. Phase change materials (PCMs) enable passive, constant-temperature thermal management but suffer from leakage and low thermal conductivity, limiting their application. In this work, a strategy of heat transfer enhancement in thermal energy storage gels by size engineering of boron nitride (BN) towards 5G thermal management is proposed. Specifically, tetradecanol (TD), whose thermal storage temperature is close to the thermal management temperature of electronic devices, is selected as the working medium. Based on the van der Waals force and hydrogen bond between TD and styrene-ethylene-butylene-styrene (SEBS), TD@SEBS@BN gels (TSBGs) with suppressed leakage are formed. The enthalpy of the TSBG is as high as 128.12 J g −1 , stably storing heat at around 35.84°C. The synergistic enhancement of heat transfer of TSBGs by large/small-sized BN is studied. An efficient heat transfer network has been established by coupling large-sized BN (average 30 μm) and small-sized BN (average 1 μm). The thermal conductivity of TSBG is increased from 0.304 W m −1 K −1 to a high value of 0.966 W m −1 K −1 (an increase of 317.76%). The efficient thermal management of 5G electronic components is finally realized using TSBGs.
研究领域:
热管理
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材料科学
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电子器件
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纳米技术
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传热
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DOI
高影响因子
ANALYST
·
2021
·Vol. 146
·期 24
·7702-7709
·
IF 4.616
Lei Huang,Shulin Tian,Wenhao Zhao,Ke Liu,Xing Ma,Jinhong Guo,Ming Yin
Acute myocardial infarction (AMI) has become a worldwide health problem because of its rapid onset and high mortality. Cardiac troponin I (cTnI) is the gold standard for diagnosis of AMI, and its rapid and accurate detection is critical for early diagnosis and management of AMI. Using a lateral flow immunoassay with upconverting nanoparticles as fluorescent probes, we developed an up-conversion fluorescence reader capable of rapidly quantifying the cTnI concentration in serum based upon the fluorescence intensity of the test and control lines on the test strip. Reliable detection of cTnI in the range 0.1–50 ng mL−1 could be achieved in 15 min, with a lower detection limit of 0.1 ng mL−1. The reader was also adapted for use on a 5th generation (5G) mobile network enabled intelligent chest pain center. Through Bluetooth wireless communication, the results achieved using the reader on an ambulance heading to a central hospital could be transmitted to a 5G smartphone and uploaded for real-time edge computing and cloud storage. An application in the 5G smartphone allows users to upload their medical information to establish dedicated electronic health records and doctors to monitor patients’ health status and provide remote medical services. Combined with mobile internet and big data, the 5G-enabled intelligent chest pain center with up-conversion lateral flow immunoassay may predict the onset of AMI and save valuable time for patients suffering an AMI.
研究领域:
远程医疗
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医学信息学
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心脏病学
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生物医学工程
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纳米技术
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移动健康
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DOI
PubMed
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
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2021
·
IF 5.302
Bing Liu,Ke Sha,Meng Fei Zhou,Kai Xin Song,Yu Hui Huang,Cheng Chao Hu
Two novel low- ε r gallates MGa 2 O 4 (M = Ca, Sr) have been synthesized via a standard solid-state reaction method. According to the X-ray diffraction results, CaGa 2 O 4 crystallizes in space group Pna2 1 with an orthorhombic symmetry, while SrGa 2 O 4 belongs to the monoclinic P2 1 / c system. Both ceramics show ever-improving microstructures with the increasing sintering temperature . The optimal microwave dielectric properties ( ε r = 9.2, Qf = 66,000 GHz, τ f =–85 ppm/°C for SrGa 2 O 4 and ε r = 10.6, Qf = 15,400 GHz, τ f =–58 ppm/°C for CaGa 2 O 4 ) are obtained when sintered at 1275 °C. A patch antenna is fabricated using SrGa 2 O 4 ceramics as the substrate, which realizes a return loss of –19.94 dB and total efficiency of –1.38 dB (72.8 % in power ratio) at 4.84 GHz. The exceptional performances indicate that SrGa 2 O 4 ceramics are promising candidates for antenna applications at the Sub-6 GHz band.
研究领域:
材料科学
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电子工程
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产品关联
DOI
高影响因子
CHINESE JOURNAL OF POLYMER SCIENCE
·
2022
·Vol. 41
·期 2
·288-296
·
IF 3.815
Tan Wan-Yi,Jian Ling-Feng,Chen Wei-Peng,Zhang Yong-Wen,Lu Xiao-Chuang,Huang Wan-Jun,Zhang Ji-Sheng,Wu Jing-Wu,Feng Jun-Li,Liu Yi-Dong,Cui Ting-Ting,Min Yong-Gang
Modified polyimides (MPIs) show great potential towards 5G communication applications, due to its excellent thermal stability, mechanical property and chemical stability as compared to most of polymers. Introducing fluoride groups or porous structure is favorable to ultra-low dielectric constant ( D k ) and dielectric loss ( D f ). However, the cost of the fluorinated MPIs is high and their synthetic processes are complicated, and porous MPIs suffer poor mechanical properties. Also, increasing the fraction of free volume is a very effective way to lower D k through introducing more ultra-low- D k air component. However, most of this kind of MPIs lag far behind the fluorinated MPIs and the porous MPIs in terms of ultra-low D f , hindering the application of MPIs in high-speed communication devices. Thus, it is highly desirable to develop intrinsic ultra-low- D k / D f MPIs at high frequency with less fluoric groups and nonporous structure. Herein, we introduce a facile and effective strategy to lower D k and D f through introducing rigid and large sterically hindered aromatic groups into MPIs. On the one hand, their large steric hindrance effect leads to low D k by increasing intrinsic free volume. On the other hand, the resulting highly stiff polymer chain and strong intermolecular interaction are favorable to reduce D f by inhibiting dipole orientations. Based on this strategy, the spirobifluorene groups are preferred. The as-prepared MPIs show excellent dielectric performance with low D k of 2.74–2.76 and low D f of 0.00599 at 10 GHz, to some extent, exceeding the multiple fluorinated MPI with D k / D f of 2.67/0.00663 at 10 GHz.
研究领域:
材料科学
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电子工程
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DOI
高影响因子
POLYMER COMPOSITES
·
2024
·
IF 4.8
Haipeng Dong,Bo Yang,Yin Guo,Khegay Lyubov Nikolaevna,Ming Yan,Li Song,Baikang Zhu,Zhi Li,Yingxue Lin,Shaohua Chai,Lu Zhang,Hengcong Tao
Regulating the dielectric properties of base stations is crucial for advancing 5G technology. This study presents the preparation of a series of graphene/polypropylene (PP) composites by blending various types and concentrations of graphene with PP using a melt blending process. The effect of different graphene types (graphene oxide, multilayer graphene, and exfoliated graphene) and concentrations (0.1, 0.5, 1, and 2 wt%) on the composites was characterized using scanning electron microscope (SEM), X-ray diffraction (XRD), differential scanning calorimeter (DSC), impedance analyzer, rotational rheometer, and thermal gravimetric analyzer (TGA). Results show that high shear force and temperature during preparation ensure the mechanical and thermal properties of the composites. Specifically, the permittivity decreased by up to 18% with the incorporation of 1% multilayer graphene (MGE). The optimal performance was achieved with MGE compared to graphene oxide (GO) and exfoliated graphene (GE), as the composites exhibited enhanced mechanical strength, thermal stability, and lower permittivitys. This work suggests significant application prospects for PP composite materials in the 5G field due to the excellent characteristics of graphene. Highlights Graphene significantly reduces the permittivity of polypropylene. Strong interfacial bonding exists between moderate amounts of graphene and PP. Graphene boosts substrate crystallization to reduce permittivity. Composite permittivity rises with filler's permittivity increase.
研究领域:
材料科学
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电子工程
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产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2020
·
IF 3.83
Zhenyu Tan,Kaixin Song,Hadi Barzegar Bafrooei,Bing Liu,Jun Wu,Junming Xu,Huixing Lin,Dawei Wang
In this paper, thermal stable Y 3 MgAl 3 SibO 12 -TiO 2 microwave composite ceramics were firstly fabricated by the high temperature solid phase reaction method. The influence of the sintering temperature , microstructure on microwave dielectric properties of Y 3 MgAl 3 SiO 12 by doping TiO 2 were investigated in detailed. TiO 2 addition reduced the ceramic sintering temperature and improved the distribution of grain size. The negative temperature coefficient of resonant frequency (τ f = −32 ppm/°C) of Y 3 MgAl 3 SiO 12 was adjusted to near zero value. 0.8Y 3 MgAl 3 SiO 12 -0.2TiO 2 ceramic sintered at 1475 °C for 6 h achieved the optimized microwave dielectric properties: ε r = 12.2, Q × f = 21,050 GHz, τ f = +5.2 ppm/°C, which indicated that 0.8Y 3 MgAl 3 SiO 12 -0.2TiO 2 is a potential candidate for dielectric patch antenna and substrate.
研究领域:
材料科学
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电子工程
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产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2023
·
IF 4.2
Ling Yuan Liao,Wen Hong Ruan,Ming Qiu Zhang,Li Weihao
The 5th generation mobile communication technology (5G) requires materials with high reliability, high dimensional stabilities, and low dielectric constant (Dk) and low loss factor (Df). However, achieving both high dimensional stabilities and low dielectric is difficult. In this work, we propose a strategy to improve dimensional stabilities of printed circuit board (PCB) substrates without reducing their dielectric properties by introducing crosslinking agents with trifluoromethyl groups and allyl groups to polymers. Polyphenylene oxide (PPO) was selected as the representative research object, and a series of cured PPO-Allyl-F with varying contents of trifluoromethyl and allyl side chains were designed and synthesized. The molecular structures of the thermosetting PPO were characterized using 1H nuclear magnetic resonance (1H NMR) and Fourier transform infrared (FTIR) spectroscopy. The isothermal curing kinetics of the thermosetting PPO were monitored with in situ FTIR. The thermal stability, mechanical properties, glass transition temperature (Tg), coefficient of thermal expansion (CTE), and dielectric properties of the cured PPO-Allyl-F materials were investigated in detail. The results show that the obtained thermosetting PPO with improved dimensional stabilities and low dielectrics has great potential for the application in high-frequency electronic circuits. This work provides a new approach for developing high-performance polymers that can address the contradiction between dielectric properties and dimensional stability.
研究领域:
材料科学
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电子工程
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产品关联
DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2025
·
IF 3.8
Gaofeng Shao,Yu Sun,Gaoyuan Yu,Weiquan Huang,Liqun Guo,Xiaogu Huang
Polymer-derived ceramics (PDCs), known for their exceptional thermal stability and adjustable dielectric characteristics, show great promise in electromagnetic wave absorption applications under extreme temperature conditions. Their multiphase and multi-heterointerface structures also enable effective low-frequency absorption for 5G applications, a crucial yet underexplored capability. In this study, nickel-modified SiCN (SiCN/Ni) ceramics were synthesized through coordination crosslinking of trace amounts of nickel-based metal-organic framework (Ni-MOF) with polysilazane precursor, followed by high-temperature pyrolysis. The investigation reveals that Ni-MOF enables the formation of both dielectric and magnetic loss components, specifically SiC nanocrystals, free carbon, and Ni 2 Si nanocrystals, during the synthesis process at reduced temperature conditions. The coexistence of electromagnetic-transparent and absorbing phases enhances impedance matching. The heterogeneous nanodomains create multiple interfaces, induce significant lattice strain, and produce abundant structural defects, which together enhance interfacial and dipole polarization effects. Notably, the optimized SiCN/Ni ceramic exhibits exceptional microwave absorption performance at low frequency, achieving a minimum reflection loss of –46.1 dB at 5.28 GHz. The low-frequency absorption bandwidths reach 0.76 and 1.0 GHz at thicknesses of 4.0 and 5.0 mm, fully covering both the n 78 band (3.3–3.8 GHz) and n 79 band (4.4–5.0 GHz) used in 5G communications. These findings present new opportunities for developing advanced lower-frequency absorbers based on dielectric PDCs.
研究领域:
材料科学
·
电磁学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）