Research Progress of Additive Manufacturing Technology in Energetic Material Field at Home and Abroad

As a subversive manufacturing technology, additive manufacturing technology has many technical advantages such as high freedom of design and not limited by complex structure of parts. The application of additive manufacturing technology to the charge molding of energetic materials will subvert the traditional manufacturing concept of energetic materials, realize the advanced charge design concept, shorten the research and development time of weapons and equipment, and improve the comprehensive performance of weapons and equipment, which is of great significance for the rapid development of high-tech weapons and equipment. This paper analyzes the research progress of additive manufacturing technology in the field of energetic materials at home and abroad and puts forward some suggestions for future research of this technology. .

Research Progress of Nano Copper Azide

The development trend of miniaturization, chipization, integration, and intelligence of new energetic devices has put forward higher requirements for primary explosives, and the toxicity of lead-containing initiating explosives has also caused increasing concerns. Nano copper azide, due to its green and high-energy characteristics, has attracted increasing interest from researchers in recent years. The research progress of Nano copper azide energetic materials is summarized from the design and preparation of composite energetic materials, and the analysis of sensitivity changes. On this basis, the key points to realize its application prospects are discussed: Develop the preparation method of carbon material modification and the combination of processing and forming to prepare new composite materials to make up for their overly sensitive defects, while giving full play to their advantages of high energy density. By comparing the existing research progress of Nano copper azide, we can understand its performance parameters more systematically, and guide the further application of Nano copper azide. .

High-Efficiency Electromagnetic Interference Shielding of rGO@FeNi/Epoxy Composites with Regular Honeycomb Structures

With the rapid development of fifth-generation mobile com-munication technology and wearable electronic devices,electromagnetic interference and radiation pollution caused by electromagnetic waves have attracted worldwide attention.Therefore,the design and development of highly efficient EMI shielding materials are of great importance.In this work,the three-dimensional graphene oxide(GO)with regular honeycomb structure(GH)is firstly constructed by sacrificial template and freeze-dry-ing methods.Then,the amino functionalized FeNi alloy particles(f-FeNi)are loaded on the GH skeleton followed by in-situ reduction to prepare rGH@FeNi aerogel.Finally,the rGH@FeNi/epoxy EMI shielding com-posites with regular honeycomb structure is obtained by vacuum-assisted impregnation of epoxy resin.Benefitting from the construction of regular honeycomb structure and electromagnetic synergistic effect,the rGH@FeNi/epoxy composites with a low rGH@FeNi mass fraction of 2.1 wt%(rGH and f-FeNi are 1.2 and 0.9 wt%,respectively)exhibit a high EMI shielding effectiveness(EMI SE)of 46 dB,which is 5.8 times of that(8 dB)for rGO/FeNi/epoxy composites with the same rGO/FeNi mass fraction.At the same time,the rGH@FeNi/epoxy composites also possess excellent thermal stability(heat-resistance index and temperature at the maximum decomposition rate are 179.1 and 389.0°C respectively)and mechanical properties(storage modulus is 8296.2 MPa).

Hydrometallurgical process for extracting bismuth from by-product of lead smelting based on methanesulfonic acid system

A new hydrometallurgical process based on the methanesulfonic acid system was proposed to extract the bismuth efficiently from by-products of lead smelting.The bismuth extraction process included electrorefining,oxidation leaching,and electrodeposition.The optimum conditions of the bismuth extraction process were determined by a single-factor test.The bismuth plate with a purity of 99.8%was obtained under the optimum conditions.Cyclic voltammetry and linear sweep voltammetry were applied to investigating the cathode reaction mechanism of electrorefining.The results show that lead deposition,bismuth deposition,and hydrogen evolution occur at the cathode,and the reactions of metals deposition are irreversible and diffusion-controlled.In addition,decreasing the temperature and acidity can improve the purity of the cathodic product(lead powder)in the electrorefining process.

Interdiscipline between optoelectronic materials and mechanical sensors:Recent advances of organic triboluminescent compounds and their applications in sensing

Triboluminescence,also as known as mechanoluminescence,is an attractive optical behavior that means the light emitted from specific organic and inorganic materials when they are subjected to external forces,such as crushing,deformation,cleaving,vibration.Inorganic triboluminescent materials show great potential for applications in sensing,such as stress sensing,damage detection.However,the triboluminescent mechanism of organic materials should be pushed further as well as their application.In this review,we summarized the history of development and possible mechanism of organic triboluminescent materials,and discussed various applications in sensing field.At the same time,inspired by the existing research progress in inorganic triboluminescent materials,we proposed the flourishing development prospects of organic triboluminescent materials in stress sensors,movement monitoring,imaging stress distribution,visualization of crack propagation,structural diagnosis,and other fields.

Gadolinium-incorporated CsPbI_(2)Br for boosting efficiency and long-term stability of all-inorganic perovskite solar cells

All-inorganic CsPbI_(2)Br perovskite solar cells(PSCs)have received extensive research interests recently.Nevertheless,their low efficiency and poor long-term stability are still obstacles for further commercial application.Herein,we demonstrate that high efficiency and exceptional long-term stability are realized by incorporating gadolinium(III)chloride(GdCl_(3))into the CsPbI_(2)Br perovskite film.The incorporation of GdCl_(3) enhances the Goldschmidt tolerance factor of CsPbI_(2)Br perovskite,yielding a dense perovskite film with small grains,thus the a-phase CsPbI_(2)Br is remarkably stabilized.Additionally,it is found that the GdCl_(3)-incorporated perovskite film achieves suppressed charge recombination and appropriate energy level alignment compared with the pristine CsPbI_(2)Br film.The noticeable increment in efficiency from14.01%(control PSC)to 16.24%is achieved for GdCl_(3)-incorporated PSC.Moreover,the nonencapsulated GdCl_(3)-incorporated PSC exhibits excellent environmental and thermal stability,remaining over 91%or90%of the original efficiency after 1200 h aging at 40%relative humidity or 480 h heating at 85℃ in nitrogen glove box respectively.The encapsulated GdCl_(3)-incorporated PSC presents an improved operational stability with over 88%of initial efficiency under maximum power point(MPP)tracking at 45℃ for1000 h.This work presents an effective ion-incorporation approach for boosting efficiency and long-term stability of all-inorganic PSCs.

Smart epidermal electrophysiological electrodes:Materials,structures,and algorithms

Epidermal electrophysiological monitoring has garnered significant attention for its potential in medical diagnosis and healthcare,particularly in continuous signal recording.However,simultaneously satisfying skin compliance,mechanical properties,environmental adaptation,and biocompatibility to avoid signal attenuation and motion artifacts is challenging,and accurate physiological feature extraction necessitates effective signal-processing algorithms.This review presents the latest advancements in smart electrodes for epidermal electrophysiological monitoring,focusing on materials,structures,and algorithms.First,smart materials incorporating self-adhesion,self-healing,and self-sensing functions offer promising solutions for long-term monitoring.Second,smart meso-structures,together with micro/nanostructures endowed the electrodes with self-adaption and multifunctionality.Third,intelligent algorithms give smart electrodes a“soul,”facilitating faster and more-accurate identification of required information via automatic processing of collected electrical signals.Finally,the existing challenges and future opportunities for developing smart electrodes are discussed.Recognized as a crucial direction for next-generation epidermal electrodes,intelligence holds the potential for extensive,effective,and transformative applications in the future.

Ratiometric fluorescence and visual sensing of ATP based on gold nanocluster-encapsulated metal-organic framework with a smartphone

Adenosine triphosphate(ATP)plays an important role in various biological processes and the ATP level is closely associated with many diseases.Herein,we designed a novel dual-emissive fluorescence nanoplatform for ATP sensing based on red emissive europium metal-organic framework(Eu-MOF)and blue emissive gold nanoclusters(AuNCs).The presence of ATP causes the decomposition of Eu-MOF owing to strong affinity of Eu3+with ATP.As a result,the red emission of Eu-MOF decreases while the blue emission of AuNCs remains unchanged.The distinct red/blue emission intensity change enables the establishment of a ratiometric fluorescent and visual sensor of ATP.Moreover,a fluorescent paper-based sensor was fabricated with the ratiometric ATP probes,which enabled easy-to-use and visual detection of ATP in serum samples with a smartphone.

Solar Shutters based on Photovoltaic Power Generation

This paper introduces a set of electrical energy-saving system for commercial office buildings,aiming at making better use of solar energy and photovoltaic power generation.Solar energy is a renewable energy source,which is inexhaustible clean energy and has great commercial application value.Based on this fact,we plan to design a unique and novel solar shutter in combination with the daily observation and the shape of solar panels.The shutter blades are equipped with an automatic light tracking system,and the angle of the blades can be adjusted in time through photoresistor induction,that is,as much solar energy as possible can be converted into electric energy for load use,and at the same time,comfortable light can be provided for the house.In essence,the system is a small photovoltaic power generation system,which runs all day with high-efficiency based on automatic sun tracking.Among them,the basic operation route includes:solar position detection,computer data processing,photovoltaic and electric volt energy conversion,circuit connection,etc.From the current debugging results,the shutter has the characteristics of humanization,high efficiency,cleanliness and so on.Through this energy-saving system,we hope to maximize the use of solar energy in the premise of low cost,so as to achieve the purpose of energy saving.

Formation mechanism of hierarchical twins in the CoCrNi medium entropy alloy

The three-dimensional hierarchical twin network has been proved to be the source of the excellent strength-ductility combination in the CoCrNi medium entropy alloy.Revealing the formation mechanism of hierarchical twins,however,remains a challenge using either the post-mortem or the in-situ microstructural characterization.In this study,the atomistic formation mechanism of hierarchical twins was investigated using molecular dynamics simulations,with special focus on the effects of strain rate and deformation temperature.Compared to the primary twin boundaries kink-driven hierarchical twinning tendency in pure FCC metals,the chemical inhomogeneity in CoCrNi can reduce the necessary kink height to trigger conjugate twins(CTWs),fascinating the formation of twin networks.At room temperature,the plastic deformation is dominated by primary twins(PTWs)and conjugate slips at a relatively lower strain rate(e.g.,5×10^(7)s^(−1)).The hierarchical twins can be activated in cases of deforming at a higher strain rate(e.g.,2×10^(8)s^(−1)).Further increasing the strain rate(e.g.,1×10^(10) s^(−1))leads to the phase-transformation induced plasticity.At cryogenic temperatures,the hierarchical twins are promoted within a large range of strain rates(e.g.,5×10^(7)–1×10^(10) s^(−1)).A higher temperature leads to the synergy of CTWs and primary slips at a lower strain rate,but hierarchical twins at a higher strain rate.On this basis,a qualitative comparison and scalable trends between experiments and simulations were revealed.The present study would not only provide the basic understanding for the twinning behavior found experimentally,but also contribute to the design of medium/high entropy alloys with excellent mechanical performances by tuning microstructures.

Enhancing thermal conductivity of silicone rubber composites by insitu constructing SiC networks:A finite-element study based on first principles calculation

Polymer composites as thermal interface materials have been widely used in modern electronic equipment.In this work,we report a novel method to prepare highly through-plane thermally conductive silicone rubber(SR)composites with vertically aligned silicon carbide fibers(VA-SiCFs)entangled by SiC nanowires(SiCNWs)networks.First,a series of carbon fibers(CFs)skeletons were fabricated in sequence of coating poor thermally conductive polyacrylonitrile-based CFs with polydopamine,icetemplated assembly,and freeze-drying processes.Furthermore,VA-SiCFs networks,i.e.,long-range continuous SiCFs-SiCNWs networks,based on the prepared CFs skeletons,were in-situ obtained via template-assisted chemical vapor deposition method.The thermal conductivity enhancement mechanism of VA-SiCFs networks on its SR composites was also intensively studied by finite element simulation,based on the first principles investigation of SiC,and Foygel’s theory.The in-situ grown VA-SiCFs networks possess high intrinsic thermal conductivity without the thermal interface between fillers,acting as the high-efficiency through-plane long-range continuous thermal conduction path,in which the SiCNWs were the in-plane“thermal spreader”.The VA-SiCFs/SR composites reached a high through-plane thermal conductivity,2.13 W/(m·K),at the filler loading of 15 vol.%,which is 868.2%,and 249.2%higher than that of pure SR sample,and random-CFs@polydopamine(PDA)/SR composites at the same content,respectively.The VA-SiCFs/SR composites also exhibited good electrical insulation performance and excellent dimensional stability,which guaranteed the stable interfacial heat transfer of high-power density electronic devices.

In-situ construction of all-scale hierarchical microstructure and thermoelectric properties of(Sr_(0.25)Ca_(0.25)Ba_(0.25)La_(0.25))TiO_(3)/Pb@Bi composite oxide ceramics

SrTiO_(3)-based oxides have been investigated as a promising n-type thermoelectric material at high temperatures;however,the relatively high thermal conductivity results in inferior thermoelectric performance.The lattice thermal conductivity can be significantly reduced by high-entropy engineering via severe lattice distortion.However,high configuration entropy also causes the deterioration of carrier mobility and restrains electron transport resulting in low electrical conductivity.In this work,the low lattice thermal conductivity of 1.7 W/(m·K)at 1073 K and significantly improved electrical conductivity of 112 S/cm from 60 S/cm can be achieved in n-type(Sr_(0.25)Ca_(0.25)Ba_(0.25)La_(0.25))TiO_(3)/Pb@Bi composites ceramics with core-shell grains of all-scale hierarchical microstructure.The effects of the complex microstructure of core-shell grains as well as the precipitated Pb@Bi particles on electrons and phonons transport properties were systematically explored.ZTmax of 0.18 was obtained for the SPS-1200,which was 1.5 times that of pure high-entropy(Ca_(0.2)Sr_(0.2)Ba_(0.2)La_(0.2)Pb_(0.2))TiO_(3)samples prepared by a solid-state method.This improvement in thermoelectric performance contributes to the addition of Bi_(2)O_(3)into the high-entropy(Sr_(0.2)Ca_(0.2)Ba_(0.2)Pb_(0.2)La_(0.2))TiO_(3)matrix resulting in multiphase core-shell grain structure combined with well-dispersed nano-sized metal Pb@Bi precipitates in the matrix.This feasible strategy of in-situ constructing all-scale hierarchical nanostructures can also be applied to enhance the performance of other thermoelectric systems.

Highly Thermally Conductive Polydimethylsiloxane Composites with Controllable 3D GO@f-CNTs Networks via Self-sacrificing Template Method

Constructing controllable thermal conduction networks is the key to efficiently improve thermal conductivities of polymer composites.In this work,graphite oxide(GO)and functionalized carbon nanotubes(f-CNTs)are combined to prepare“Line-Plane”-like hetero-structured thermally conductive GO@f-CNTs fillers,which are then performed to construct controllable 3D GO@f-CNTs thermal conduction networks via selfsacrificing template method based on oxalic acid.Subsequently,thermally conductive GO@f-CNTs/polydimethylsiloxane(PDMS)composites are fabricated via casting method.When the size of oxalic acid is 0.24 mm and the volume fraction of GO@f-CNTs is 60 vol%,GO@f-CNTs/PDMS composites present the optimal thermal conductivity coefficient(λ,4.00 W·m^(-1)·K^(-1)),about 20 times that of theλof neat PDMS(0.20 W·m^(-1)·K^(-1)),also much higher than theλ(2.44 W·m^(-1)·K^(-1))of GO/f-CNTs/PDMS composites with the same amount of randomly dispersed fillers.Meanwhile,the obtained GO@f-CNTs/PDMS composites have excellent thermal stability,whoseλdeviation is only about 3%after 500 thermal cycles(20-200℃).

Significant Reduction of Interfacial Thermal Resistance and Phonon Scattering in Graphene/Polyimide Thermally Conductive Composite Films for Thermal Management

The developing flexible electronic equipment are greatly affected by the rapid accumulation of heat,which is urgent to be solved by thermally conductive polymer composite films.However,the interfacial thermal resistance(ITR)and the phonon scattering at the interfaces are the main bottlenecks limiting the rapid and efficient improvement of thermal conductivity coefficients(λ)of the polymer composite films.Moreover,few researches were focused on characterizing ITR and phonon scattering in thermally conductive polymer composite films.In this paper,graphene oxide(GO)was aminated(NH_(2)-GO)and reduced(NH_(2)-rGO),then NH_(2)-rGO/polyimide(NH_(2)-rGO/PI)thermally conductive composite films were fabricated.Raman spectroscopy was utilized to innovatively characterize phonon scattering and ITR at the interfaces in NH_(2)-rGO/PI thermally conductive composite films,revealing the interfacial thermal conduction mechanism,proving that the amination optimized the interfaces between NH_(2)-rGO and PI,reduced phonon scattering and ITR,and ultimately improved the interfacial thermal conduction.The in-planeλ(λ∥)and through-planeλ(λ_(⊥))of 15 wt%NH_(2)-rGO/PI thermally conductive composite films at room temperature were,respectively,7.13 W/mK and 0.74 W/mK,8.2 timesλ∥(0.87 W/mK)and 3.5 timesλ_(⊥)(0.21 W/mK)of pure PI film,also significantly higher thanλ∥(5.50 W/mK)andλ_(⊥)(0.62 W/mK)of 15 wt%rGO/PI thermally conductive composite films.Calculation based on the effective medium theory model proved that ITR was reduced via the amination of rGO.Infrared thermal imaging and finite element simulation showed that NH_(2)-rGO/PI thermally conductive composite films obtained excellent heat dissipation and efficient thermal management capabilities on the light-emitting diodes bulbs,5G high-power chips,and other electronic equipment,which are easy to generate heat severely.

Synthesis, Structure and Property of a Metal-organic Framework Based on 9-(2,6-Dicarboxy-pyridin-4-yl)-9H-carbazole-3,6-dicarboxylic Acid

A new terbium(III) metal-organic framework [Tb(HL)(H2O)](Tb L) based on a new synthetic ligand 9-(2,6-dicarboxy-pyridin-4-yl)-9 H-carbazole-3,6-dicarboxylic acid(H4 L) has been synthesized under solvothermal conditions. Its structure was determined by single-crystal X-ray diffraction analysis, and further characterized by powder X-ray diffraction analysis and IR spectra. The title complex crystallizes in trigonal space group P3212 with a = b = 13.6491(11), c = 32.345(3) ?, γ = 120°, V = 5218.5(10) ?~3, C(42)H(20)N4O(17)Tb2, Mr = 1170.46, Dc = 1.117 g/cm^3, μ(Mo Kα) = 2.065 mm^(-1), F(000) = 1698, GOF = 1.054, Z = 3, the final R = 0.0384 and wR = 0.0771 for 5223 observed reflections(I > 2s(I)). In Tb L, the tri-bridged binuclear Tb2 units are bibridged by two carbazole-3,6-dicarboxylate moieties to lead to the homochiral parallel arranged helical chains, which are further connected by 2,6-pyridinedicarboxylate moieties to produce the chiral neutral 3 D framework. There are there kinds of 1 D channels in the framework with the channel space occupying 53.3% of the total volume. TbL exhibits intense characteristic green emission of Tb^(3+) ions.

Designed preparation of CoS/Co/MoC nanoparticles incorporated in N and S dual-doped porous carbon nanofibers for high-performance Zn-air batteries

The development of low-cost and highly efficient bifunctional electrocatalysts toward oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is of critical importance for clean energy devices such as fuel cells and metal-air batteries.Herein,a sophisticated na nostructure composed of CoS,Co and MoC nanoparticles incorporated in N and S dual-doped porous carbon nanofibers(CoS/Co/MoC-N,SPCNFs)as a high-efficiency bifunctional electrocatalyst is designed and synthesized via an efficient multistep strategy.The as-prepared CoS/Co/MoC-N,S-PCNFs exhibit a positive half-wave potential(E1/2)of0.871 V for ORR and a low overpotential of 289 mV at 10 mA/cm^(2) for OER,outperforming the non-noble metal-based catalysts reported.Furthermore,the assembled Zn-air battery based on CoS/Co/MoC-N,SPCNFs delivers an excellent power density(169.1 mW/cm^(2)),a large specific capacity(819.3 mAh/g)and robust durability,demonstrating the great potential of the as-developed bifunctional electrocatalyst in practical applications.This work is expected to inspire the design of advanced bifunctional nonprecious metal-based electrocatalysts for energy storage.

Thermally conductive polyvinyl alcohol composite films via introducing hetero-structured MXene@silver fillers

Ag nanoparticles were in-situ grown on the surface of MXene nanosheets to prepare thermally conductive hetero-structured MXene@Ag fillers.With polyvinyl alcohol(PVA)as the polymer matrix,thermally conductive MXene@Ag/PVA composite films were fabricated by the processes of solution blending,pouring,evaporative self-assembly.With the same mass fraction,MXene@Ag-III(MXene/Ag,2:1,w/w)presents more significant improvement in thermal conductivity coefficient(λ)than MXene@Ag,single MXene,Ag,simply blending MXene/Ag.MXene@Ag-III/PVA composite films show dual functions of excellent thermal conductivity and electromagnetic interference(EMI)shielding.When the mass fraction of MXene@Ag-III is 60 wt.%,the in-planeλ(λ_(∥)),through-planeλ(λ_(⊥)),EMI shielding effectiveness(EMI SE)are 3.72 and 0.41 W/(m∙K),32 dB,which are increased by 3.1,1.3,105.7 times than those of pure PVA film(0.91 and 0.18 W/(m∙K),0.3 dB),respectively.The 60 wt.%MXene@Ag-III/PVA composite film also has satisfying mechanical and thermal properties,with Young’s modulus,glass transition temperature,heat resistance index of 3.8 GPa,58.5 and 175.3℃,respectively.

Branched Fluorine/Adamantane Interfacial Compatibilizer for PBO Fibers/Cyanate Ester Wave-Transparent Laminated Composites

Comprehensive Summary Branched fluorine/adamantane PBO precursor(preFABPBO),synthesized via random co-condensation between 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoro propane,1,3-adamantanedicarbonyl dichloride,and trimesoyl chloride,is performed as interfacial compatibilizer,bisphenol A dicyanate ester(BADCy)resin as polymer matrix,and poly(p-phenylene-2,6-benzobisoxazole)(PBO)fibers as reinforcements to prepare PBO fibers/FABPBO-BADCy wave-transparent laminated composites by high temperature molding.The mechanical properties,wave-transparent performances,and heat resistances of PBO fibers/BADCy composites are simultaneously improved by the addition of preFABPBO.The interlaminar shear strength(ILSS)and flexural strength of PBO fibers/FABPBO-BADCy composites are 48.9 and 665.3 MPa,respectively,increased by 33.2%and 13.3%compared to those of PBO fibers/BADCy composites(36.7 and 587.4 MPa).The dielectric constant and dielectric loss values at 106 Hz are 2.53 and 0.003,respectively,lower than those of PBO fibers/BADCy composites(3.06 and 0.006),and the corresponding wave transmission efficiency is 94.8%,which also presents excellent stability over the wide temperature(25-200℃)and frequency range(103-107 Hz and 8.2-12.4 GHz).Meanwhile,the heat resistance index and glass transition temperature are 229.9℃and 247.5℃,also better than those of PBO fibers/BADCy composites(229.6℃and 247.1℃).

Block copolymer functionalized quartz fibers/cyanate ester wave-transparent laminated composites

A block copolymer of PDMS-b-PGMA is synthesized by polymerizing glycidyl methacrylate(GMA)via reversible addition-fragmentation chain transfer(RAFT)polymerization applying a polydimethylsiloxane(PDMS)based macro-RAFT agent,which is then performed to functionalize the quartz fibers(QFs@PDMS-b-PGMA)via a simple coating process.Finally,the QFs@PDMS-b-PGMA/bisphenol A dicyanate ester(BADCy)wave-transparent laminated composites are fabricated by high-temperature molding.Nuclear magnetic resonance(NMR)spectroscopy,Fourier transform infrared(FT-IR)spectroscopy and size ex-clusion chromatography(SEC)demonstrate the successful preparation of PDMS-b-PGMA with expected structure.When the molar mass and coating amount of PDMS-b-PGMA are respectively 8100 g/mol and 2.0 wt.%,QFs@PDMS-b-PGMA/BADCy wave-transparent laminated composites present optimal mechan-ical properties and wave-transparent performance.The interlaminar shear strength(ILSS)and flexural strength are 53.6 and 552.0 MPa,respectively.Meanwhile,the dielectric constant and dielectric loss val-ues are 2.61 and 0.0028 at 1 MHz(wave transmittance of 93.8%),showing good stability at different frequencies(102-106 Hz and 8.4-12.4 GHz)and temperatures(25-250℃).

Low dielectric constant and highly intrinsic thermal conductivity fluorine-containing epoxy resins with ordered liquid crystal structures

Epoxy resins with a high dielectric constant and low intrinsic thermal conductivity coefficient cannot meet the current application requirements of advanced electronic and electrical equipment.Therefore,novel fluorine-containing liquid crystal epoxy compounds(TFSAEy)with fluorinated groups,biphenyl units,and flexible alkyl chains are first synthesized via amidation and esterification reactions.Then,4,4′-diaminodiphenylmethane(DDM)is used as a curing agent to prepare the corresponding fluorine-containing liquid crystal epoxy resins.The obtained dielectric constant(ε)and dielectric loss(tanδ)values of TFSAEy/DDM at 1 MHz are 2.54 and 0.025,respectively,which are significantly lower than those of conventional epoxy resins(E-51/DDM,3.52 and 0.038).Additionally,the intrinsic thermal conductivity coefficient(λ)of TFSAEy/DDM is 0.36 W/(m⋅K),71.4%higher than that of E-51/DDM(0.21 W/(m⋅K)).Meanwhile,the corresponding elastic modulus,hardness,glass transition temperature,and heat resistance index of TFSAEy/DDM are 5.73 GPa,0.35 GPa,213.5◦C,and 188.7℃,respectively,all superior to those of E-51/DDM(3.68 GPa,0.27 GPa,107.2℃,and 174.8℃),presenting potential application in high-heating electronic component packaging and printed circuit boards.