基于热膨胀微球的轻质聚合物复合材料的制备及其力学与电磁屏蔽性能研究

  随着5G时代的到来，通讯技术和电子设备得到快速发展，所带来的电磁干扰(Electromagnetic interference，EMI)也日益严重，不仅会引起信号失真，导致设备故障，还会损害人体健康。因此，能有效抑制电磁干扰的电磁屏蔽材料引起了人们的广泛关注。特别是，兼具超低的密度和较好的屏蔽性能等特性的泡沫型聚合物基电磁屏蔽复合材料在轻薄电子器件和航空航天等领域表现出广泛的应用前景。

  泡沫型聚合物基电磁屏蔽复合材料往往是通过减少聚合物基质来形成开孔结构，很难兼具优异的压缩强度和回弹性。此外，实现泡沫型聚合物基电磁屏蔽复合材料更高的屏蔽性能，往往需要大量增加导电填料含量，进一步导致复合材料力学强度下降。因此，开发兼具轻质、高屏蔽性能、低填料含量、良好力学性能等特性的聚合物基电磁屏蔽复合材料是一个重要需求。本文基于低密度、可发泡、内部填充气体闭孔结构的热膨胀微球(Expandable Polymer Microspheres，EPM)，开发一种通过限域-热膨胀成型工艺制备轻质复合材料的方法，并通过该方法在微球界面构造连续致密的三维导电网络，在极大降低填料含量的同时，保证泡沫的力学性能和导电性能。主要研究内容分为以下三个部分：

  (1) 热膨胀聚合物微球基复合材料制备方法与力学性能研究

  热膨胀微球是一种具有微米级尺寸的空心聚合物微球。在封闭空间内，热膨胀微球受热而体积发生膨胀（限域-热膨胀），大量的微球之间互相挤压、微球外壳界面粘接而形成具有定型结构与力学强度的复合材料。代表性地选取流体(硅油)、弹性体(有机硅凝胶)及硬质热固性聚合物材料(环氧树脂)三种不同粘弹性特征（热成型后）的液体材料，与热膨胀微球复合，通过限域-热膨胀法成功制备了微球/硅油复合材料、微球/硅凝胶复合材料和微球/环氧复合材料。EDS能谱分析表明，在复合材料内部，硅油、硅凝胶或环氧主要分布微球界面处，并形成三维连续相。热膨胀微球/硅油复合材料密度为0.139 g/cm³，在20%压缩应变时的压缩强度为0.331 MPa。微球/硅凝胶复合材料密度为0.09 g/cm³，拥有0.271 MPa的压缩强度。微球/环氧复合材料密度为0.145 g/cm³，压缩强度为0.614 MPa。在没有化学交联反应硅油体系中，微球复合材料依旧具有良好压缩强度。在具有化学交联的硅凝胶和环氧体系中，微球复合材料起到了力学调控作用。这表明热膨胀微球、限域-热膨胀法在制备轻质聚合物基复合材料上具有广阔的应用前景，并为构造三维导电屏蔽连续相奠定了基础。

  (2) 热膨胀聚合物微球/片状银粉电磁屏蔽材料的制备和性能研究

  将热膨胀微球与片状银粉混合，通过限域-热膨胀法制备了热膨胀微球/片状银粉(EPM/AgF)复合材料。AgF体积分数为2.57 vol%的复合材料密度为0.328 g/cm³，电导率为973.56 S/m，平均电磁屏蔽效能为37.7 dB (厚度为2 mm)，是一种轻质、高效屏蔽性能的电磁屏蔽材料。实验表明AgF主要分布在热膨胀微球界面处，形成了连续的隔离结构网络，验证了基于热膨胀微球的限域-热膨胀法可有效制备具有轻质、隔离导电网络结构特征的电磁屏蔽材料，是一种制备轻质电磁干扰屏蔽材料的便捷方法。

  (3) 热膨胀聚合物微球/银纳米线电磁屏蔽材料的制备和性能研究

  进一步综合利用隔离结构和银纳米线长径比的特点降低导电填料的填充量和复合材料密度。一维结构的高导电性纳米银线的乙醇分散液与热膨胀微球混合，经过抽滤干燥等工艺后，通过限域-热膨胀法制备了热膨胀微球/银纳米线(EPM/AgNWs)复合材料。EPM/AgNWs复合材料具有低的密度(0.061 g/cm³)、低的导电填料含量(0.127 vol%银)、较高的压缩强度(0.341 MPa)以及较高的单位厚度比屏蔽效能(SSE/d = 7954 dB·cm²/g，厚度为1 mm时，其屏蔽效能为48.52 dB)。最后通过有限元分析方法进一步讨论了EPM/AgNWs复合材料的EMI屏蔽机制和力学特性，并通过近场屏蔽测试直观地验证了EPM/AgNWs复合材料在实际应用中具有良好的屏蔽密封性。热膨胀微球/银纳米线复合材料为高压缩强度、可回弹性、轻质、低填料含量的高效电磁屏蔽材料的研究提供了新思路。

[1] Wan Y, Xiong P, Liu J, et al. Ultrathin, Strong, and Highly Flexible Ti3C2Tx MXene/Bacterial Cellulose Composite Films for High-Performance Electromagnetic Interference Shielding [J]. ACS Nano, 2021, 15(5): 8439-8449.
[2] 许亚东. 聚合物电磁屏蔽复合材料的结构设计与性能研究 [D]; 中北大学, 2019.
[3] Zhu R, Li Z, Deng G, et al. Anisotropic Magnetic Liquid Metal Film for Wearable Wireless Electromagnetic Sensing and Smart Electromagnetic Interference Shielding [J]. Nano Energy, 2022, 92: 106700.
[4] Wang M, Tang X-H, Cai J-H, et al. Construction, Mechanism and Prospective of Conductive Polymer Composites with Multiple Interfaces for Electromagnetic Interference Shielding: A Review [J]. Carbon, 2021, 177: 377-402.
[5] Yao B, Hong W, Chen T, et al. Highly Stretchable Polymer Composite with Strain-Enhanced Electromagnetic Interference Shielding Effectiveness [J]. Advanced Materials, 2020, 32: 1907499.
[6] 任威. 导热功能化电磁屏蔽复合材料的制备与性能研究 [D]; 中北大学, 2021.
[7] Lei Z, Tian D, Liu X, et al. Electrically Conductive Gradient Structure Design of Thermoplastic Polyurethane Composite Foams for Efficient Electromagnetic Interference Shielding and Ultra-Low Microwave Reflectivity [J]. Chemical Engineering Journal, 2021, 424: 130365.
[8] Zhan Y, Wang J, Zhang K, et al. Fabrication of a Flexible Electromagnetic Interference Shielding Fe3O4@Reduced Graphene Oxide/Natural Rubber Composite with Segregated Network [J]. Chemical Engineering Journal, 2018, 344: 184-193.
[9] Duan H, Zhu H, Gao J, et al. Asymmetric Conductive Polymer Composite Foam for Absorption Dominated Ultra-Efficient Electromagnetic Interference Shielding with Extremely Low Reflection Characteristics [J]. Journal of Materials Chemistry A, 2020, 8(18): 9146-9159.
[10] Song P, Liu B, Liang C, et al. Lightweight, Flexible Cellulose-Derived Carbon Aerogel@Reduced Graphene Oxide/PDMS Composites with Outstanding EMI Shielding Performances and Excellent Thermal Conductivities [J]. Nano-Micro Letters, 2021, 13(1): 91.
[11] Zhang H, Zhang G, Li J, et al. Lightweight, Multifunctional Microcellular PMMA/Fe3O4@MWCNTs Nanocomposite Foams with Efficient Electromagnetic Interference Shielding [J]. Composites Part A: Applied Science and Manufacturing, 2017, 100: 128-138.
[12] Wang G, Wang L, Mark L H, et al. Ultralow-Threshold and Lightweight Biodegradable Porous PLA/MWCNT with Segregated Conductive Networks for High-Performance Thermal Insulation and Electromagnetic Interference Shielding Applications [J]. ACS Applied Materials & Interfaces, 2018, 10(1): 1195-1203.
[13] Zeng Z, Chen M, Pei Y, et al. Ultralight and Flexible Polyurethane/Silver Nanowire Nanocomposites with Unidirectional Pores for Highly Effective Electromagnetic Shielding [J]. ACS Applied Materials & Interfaces, 2017, 9(37): 32211-32219.
[14] Yang J, Liao X, Wang G, et al. Gradient Structure Design of Lightweight and Flexible Silicone Rubber Nanocomposite Foam for Efficient Electromagnetic Interference Shielding [J]. Chemical Engineering Journal, 2020, 390: 124589.
[15] Wang Y-Y, Sun W-J, Yan D-X, et al. Ultralight Carbon Nanotube/Graphene/Polyimide Foam with Heterogeneous Interfaces for Efficient Electromagnetic Interference Shielding and Electromagnetic Wave Absorption [J]. Carbon, 2021, 176: 118-125.
[16] Koo C M, Sambyal P, Iqbal A. Two-Dimensional Materials for Electromagnetic Shielding [M]. 2021.
[17] Wei B, zhang L, Yang S. Polymer Composites with Expanded Graphite Network with Superior Thermal Conductivity and Electromagnetic Interference Shielding Performance [J]. Chemical Engineering Journal, 2021, 404: 126437.
[18] Brillaud E, Piotrowski A, de Seze R. Effect of an Acute 900 MHz GSM Exposure on Glia in the Rat Brain: A Time-Dependent Study [J]. Toxicology, 2007, 238(1): 23-33.
[19] Mirkhani S A, Iqbal A, Kwon T, et al. Reduction of Electrochemically Exfoliated Graphene Films for High-Performance Electromagnetic Interference Shielding [J]. ACS Applied Materials & Interfaces, 2021, 13(13): 15827-15836.
[20] 赵慧慧. 泡沫型电磁屏蔽复合材料的制备及性能研究 [D]; 南京航空航天大学, 2014.
[21] 李婷婷. PMMA/MWCNTs微孔发泡复合材料制备方法及电磁屏蔽性能研究 [D]; 山东大学, 2019.
[22] Iqbal A, Sambyal P, Koo C M. 2D MXenes for Electromagnetic Shielding: A Review [J]. Advanced Functional Materials, 2020, 30(47): 2000883.
[23] Dong J, Luo S, Ning S, et al. MXene-Coated Wrinkled Fabrics for Stretchable and Multifunctional Electromagnetic Interference Shielding and Electro/Photo-Thermal Conversion Applications [J]. ACS Applied Materials & Interfaces, 2021, 13(50): 60478-60488.
[24] Chung D D L. Electromagnetic Interference Shielding Effectiveness of Carbon Materials [J]. Carbon, 2001, 39(2): 279-285.
[25] 曹斌. 多孔碳/金属纳米复合材料的制备及电磁性能研究 [D]; 上海交通大学, 2010.
[26] Chen Y, Li J, Li T, et al. Recent Advances in Graphene-Based Films for Electromagnetic Interference Shielding: Review and Future Prospects [J]. Carbon, 2021, 180: 163-184.
[27] Choi H K, Lee A, Park M, et al. Hierarchical Porous Film with Layer-by-Layer Assembly of 2D Copper Nanosheets for Ultimate Electromagnetic Interference Shielding [J]. ACS Nano, 2021, 15(1): 829-839.
[28] Park J, Lee J W, Choi H J, et al. Electromagnetic Interference Shielding Effectiveness of Sputtered NiFe/Cu Multi-Layer Thin Film at High Frequencies [J]. Thin Solid Films, 2019, 677: 130-136.
[29] Pandey R, Tekumalla S, Gupta M. Magnesium-Iron Micro-Composite for Enhanced Shielding of Electromagnetic Pollution [J]. Composites Part B: Engineering, 2019, 163: 150-157.
[30] Parit M, Du H, Zhang X, et al. Polypyrrole and Cellulose Nanofiber Based Composite Films with Improved Physical and Electrical Properties for Electromagnetic Shielding Applications [J]. Carbohydrate Polymers, 2020, 240: 116304.
[31] Wang J, Li Q, Li K, et al. Ultra-High Electrical Conductivity in Filler-Free Polymeric Hydrogels toward Thermoelectrics and Electromagnetic Interference Shielding [J]. Advanced Materials, 2022, 34(12): 2109904.
[32] Lyu J, Zhao X, Hou X, et al. Electromagnetic Interference Shielding Based on a High Strength Polyaniline-Aramid Nanocomposite [J]. Composites Science and Technology, 2017, 149: 159-165.
[33] Zhang Y, Pan T, Yang Z. Flexible Polyethylene Terephthalate/Polyaniline Composite Paper with Bending Durability and Effective Electromagnetic Shielding Performance [J]. Chemical Engineering Journal, 2020, 389: 124433.
[34] Sun F, Xu J, Liu T, et al. An Autonomously Ultrafast Self-Healing, Highly Colourless, Tear-Resistant and Compliant Elastomer Tailored for Transparent Electromagnetic Interference Shielding Films Integrated in Flexible and Optical Electronics [J]. Materials Horizons, 2021, 8(12): 3356-3367.
[35] Tian D, Xu Y, Wang Y, et al. In-Situ Metallized Carbon Nanotubes/Poly(Styrene-Butadiene-Styrene) (CNTs/SBS) Foam for Electromagnetic Interference Shielding [J]. Chemical Engineering Journal, 2021, 420: 130482.
[36] Nguyen V-T, Min B K, Yi Y, et al. MXene(Ti3C2Tx)/Graphene/PDMS Composites for Multifunctional Broadband Electromagnetic Interference Shielding Skins [J]. Chemical Engineering Journal, 2020, 393: 124608.
[37] Li J, Zhang X, Ding Y, et al. Multifunctional Carbon Fiber@NiCo/Polyimide Films with Outstanding Electromagnetic Interference Shielding Performance [J]. Chemical Engineering Journal, 2022, 427: 131937.
[38] Liu Y, Lu M, Wu K, et al. Anisotropic Thermal Conductivity and Electromagnetic Interference Shielding of Epoxy Nanocomposites Based on Magnetic Driving Reduced Graphene Oxide@Fe3O4 [J]. Composites Science and Technology, 2019, 174: 1-10.
[39] Li J, Liu X, Feng Y, et al. Recent Progress in Polymer/Two-Dimensional Nanosheets Composites with Novel Performances [J]. Progress in Polymer Science, 2022, 126: 101505.
[40] Zeng Z, Wang C, Siqueira G, et al. Nanocellulose-MXene Biomimetic Aerogels with Orientation-Tunable Electromagnetic Interference Shielding Performance [J]. Advanced Science, 2020, 7(15): 2000979.
[41] Sun R, Zhang H-B, Liu J, et al. Highly Conductive Transition Metal Carbide/Carbonitride(MXene)@Polystyrene Nanocomposites Fabricated by Electrostatic Assembly for Highly Efficient Electromagnetic Interference Shielding [J]. Advanced Functional Materials, 2017, 27(45): 1702807.
[42] Fan X, Zhang G, Gao Q, et al. Highly Expansive, Thermally Insulating Epoxy/Ag Nanosheet Composite Foam for Electromagnetic Interference Shielding [J]. Chemical Engineering Journal, 2019, 372: 191-202.
[43] Wan S, Li X, Chen Y, et al. High-Strength Scalable MXene Films through Bridging-Induced Densification [J]. Science, 2021, 374: 96-99.
[44] Liang C, Gu Z, Zhang Y, et al. Structural Design Strategies of Polymer Matrix Composites for Electromagnetic Interference Shielding: A Review [J]. Nano-Micro Letters, 2021, 13(1): 181.
[45] Du Y, Xu J, Fang J, et al. Ultralight, Highly Compressible, Thermally Stable MXene/Aramid Nanofiber Anisotropic Aerogels for Electromagnetic Interference Shielding [J]. Journal of Materials Chemistry A, 2022, 10(12): 6690-6700.
[46] Song Q, Ye F, Yin X, et al. Carbon Nanotube–Multilayered Graphene Edge Plane Core–Shell Hybrid Foams for Ultrahigh-Performance Electromagnetic-Interference Shielding [J]. Advanced Materials, 2017, 29(31): 1701583.
[47] Yin J, Zhang J, Zhang S, et al. Flexible 3d Porous Graphene Film Decorated with Nickel Nanoparticles for Absorption-Dominated Electromagnetic Interference Shielding [J]. Chemical Engineering Journal, 2021, 421: 129763.
[48] Soares B G. Ionic Liquid: A Smart Approach for Developing Conducting Polymer Composites: A Review [J]. Journal of Molecular Liquids, 2018, 262: 8-18.
[49] Li Y, Sun N, Liu J, et al. Multifunctional BiFeO3 Composites: Absorption Attenuation Dominated Effective Electromagnetic Interference Shielding and Electromagnetic Absorption Induced by Multiple Dielectric and Magnetic Relaxations [J]. Composites Science and Technology, 2018, 159: 240-250.
[50] Jia Z, Wang C, Feng A, et al. A Low-Dielectric Decoration Strategy to Achieve Absorption Dominated Electromagnetic Shielding Material [J]. Composites Part B: Engineering, 2020, 183: 107690.
[51] Liang C, Wang Z, Wu L, et al. Light and Strong Hierarchical Porous Sic Foam for Efficient Electromagnetic Interference Shielding and Thermal Insulation at Elevated Temperatures [J]. ACS Applied Materials & Interfaces, 2017, 9(35): 29950-29957.
[52] Iqbal A, Shahzad F, Hantanasirisakul K, et al. Anomalous Absorption of Electromagnetic Waves by 2D Transition Metal Carbonitride Ti3C2Tx (MXene) [J]. Science, 2020, 369(6502): 446-450.
[53] Lipton J, Röhr J A, Dang V, et al. Scalable, Highly Conductive, and Micropatternable MXene Films for Enhanced Electromagnetic Interference Shielding [J]. Matter, 2020, 3(2): 546-557.
[54] Iqbal A, Hong J, Ko T Y, et al. Improving Oxidation Stability of 2D MXenes: Synthesis, Storage Media, and Conditions [J]. Nano Convergence, 2021, 8(1): 9.
[55] Kim T, Pak S, Lim J, et al. Electromagnetic Interference Shielding with 2D Copper Sulfide [J]. ACS Applied Materials & Interfaces, 2022, 14(11): 13499-13506.
[56] Zhang D, Liang S, Chai J, et al. Highly Effective Shielding of Electromagnetic Waves in MoS2 Nanosheets Synthesized by a Hydrothermal Method [J]. Journal of Physics and Chemistry of Solids, 2019, 134: 77-82.
[57] Zong P-A, Yoo D, Zhang P, et al. Flexible Foil of Hybrid TaS2/Organic Superlattice: Fabrication and Electrical Properties [J]. Small, 2020, 16(15): 1901901.
[58] Barani Z, Kargar F, Ghafouri Y, et al. Electrically Insulating Flexible Films with Quasi-1d Van Der Waals Fillers as Efficient Electromagnetic Shields in the GHz and Sub-THz Frequency Bands [J]. Advanced Materials, 2021, 33(11): 2007286.
[59] Xu J, Li R, Ji S, et al. Multifunctional Graphene Microstructures Inspired by Honeycomb for Ultrahigh Performance Electromagnetic Interference Shielding and Wearable Applications [J]. ACS Nano, 2021, 15(5): 8907-8918.
[60] Yang R, Gui X, Yao L, et al. Ultrathin, Lightweight, and Flexible CNT Buckypaper Enhanced Using MXenes for Electromagnetic Interference Shielding [J]. Nano-Micro Letters, 2021, 13(1): 66.
[61] Wei Q, Pei S, Qian X, et al. Superhigh Electromagnetic Interference Shielding of Ultrathin Aligned Pristine Graphene Nanosheets Film [J]. Advanced Materials, 2020, 32(14): 1907411.
[62] Wang W-y, Ma X, Shao Y-w, et al. Flexible, Multifunctional, and Thermally Conductive Nylon/Graphene Nanoplatelet Composite Papers with Excellent EMI Shielding Performance, Improved Hydrophobicity and Flame Resistance [J]. Journal of Materials Chemistry A, 2021, 9(8): 5033-5044.
[63] Wang G, Zhao Y, Yang F, et al. Multifunctional Integrated Transparent Film for Efficient Electromagnetic Protection [J]. Nano-Micro Letters, 2022, 14(1): 65.
[64] Jia L-C, Yan D-X, Liu X, et al. Highly Efficient and Reliable Transparent Electromagnetic Interference Shielding Film [J]. ACS Applied Materials & Interfaces, 2018, 10(14): 11941-11949.
[65] Kim Y, Hyeong S-K, Choi Y, et al. Transparent and Flexible Electromagnetic Interference Shielding Film Using Ito Nanobranches by Internal Scattering [J]. ACS Applied Materials & Interfaces, 2021, 13(51): 61413-61421.
[66] Chen D, Wang D, Yang Y, et al. Self-Healing Materials for Next-Generation Energy Harvesting and Storage Devices [J]. Advanced Energy Materials, 2017, 7(23): 1700890.
[67] Zou L, Lan C, Zhang S, et al. Near-Instantaneously Self-Healing Coating toward Stable and Durable Electromagnetic Interference Shielding [J]. Nano-Micro Letters, 2021, 13(1): 190.
[68] Wang T, Kong W-W, Yu W-C, et al. A Healable and Mechanically Enhanced Composite with Segregated Conductive Network Structure for High-Efficient Electromagnetic Interference Shielding [J]. Nano-Micro Letters, 2021, 13(1): 162.
[69] Ma Z, Kang S, Ma J, et al. Ultraflexible and Mechanically Strong Double-Layered Aramid Nanofiber–Ti3C2Tx MXene/Silver Nanowire Nanocomposite Papers for High-Performance Electromagnetic Interference Shielding [J]. ACS Nano, 2020, 14(7): 8368-8382.
[70] Pang K, Liu X, Liu Y, et al. Highly Conductive Graphene Film with High-Temperature Stability for Electromagnetic Interference Shielding [J]. Carbon, 2021, 179: 202-208.
[71] Cheng Y, Li X, Qin Y, et al. Hierarchically Porous Polyimide/Ti3C2Tx Film with Stable Electromagnetic Interference Shielding after Resisting Harsh Conditions [J]. Science Advances, 2021, 7: eabj1663.
[72] Wang Y, Peng H-K, Li T-T, et al. MXene-Coated Conductive Composite Film with Ultrathin, Flexible, Self-Cleaning for High-Performance Electromagnetic Interference Shielding [J]. Chemical Engineering Journal, 2021, 412: 128681.
[73] Xiang Z, Shi Y, Zhu X, et al. Flexible and Waterproof 2D/1D/0D Construction of MXene-Based Nanocomposites for Electromagnetic Wave Absorption, EMI Shielding, and Photothermal Conversion [J]. Nano-Micro Letters, 2021, 13(1): 150.
[74] Ji X, Chen D, Shen J, et al. Flexible and Flame-Retarding Thermoplastic Polyurethane-Based Electromagnetic Interference Shielding Composites [J]. Chemical Engineering Journal, 2019, 370: 1341-1349.
[75] 康松磊. 轻质高效聚合物基电磁屏蔽复合材料的结构设计与性能研究 [D]; 陕西科技大学, 2021.
[76] 朱慧鑫. 低反射特征聚合物基电磁屏蔽复合材料的制备与性能研究 [D]; 中北大学, 2019.
[77] Zhao B, Zhao C, Li R, et al. Flexible, Ultrathin, and High-Efficiency Electromagnetic Shielding Properties of Poly(Vinylidene Fluoride)/Carbon Composite Films [J]. ACS Applied Materials & Interfaces, 2017, 9(24): 20873-20884.
[78] Kaushal A, Singh V. Electromagnetic Interference Shielding Response of Multiwall Carbon Nanotube/Polypropylene Nanocomposites Prepared Via Melt Processing Technique [J]. Polymer Composites, 2021, 42(3): 1148-1154.
[79] Yu W-C, Zhang G-Q, Liu Y-H, et al. Selective Electromagnetic Interference Shielding Performance and Superior Mechanical Strength of Conductive Polymer Composites with Oriented Segregated Conductive Networks [J]. Chemical Engineering Journal, 2019, 373: 556-564.
[80] Sharif F, Arjmand M, Moud A A, et al. Segregated Hybrid Poly(Methyl Methacrylate)/Graphene/Magnetite Nanocomposites for Electromagnetic Interference Shielding [J]. ACS Applied Materials & Interfaces, 2017, 9(16): 14171-14179.
[81] Cui C-H, Yan D-X, Pang H, et al. Formation of a Segregated Electrically Conductive Network Structure in a Low-Melt-Viscosity Polymer for Highly Efficient Electromagnetic Interference Shielding [J]. ACS Sustainable Chemistry & Engineering, 2016, 4(8): 4137-4145.
[82] Zeng Z, Jin H, Chen M, et al. Lightweight and Anisotropic Porous MWCNT/WPU Composites for Ultrahigh Performance Electromagnetic Interference Shielding [J]. Advanced Functional Materials, 2016, 26(2): 303-310.
[83] Yuan M, Fei Y, Zhang H, et al. Electromagnetic Asymmetric Films Comprise Metal Organic Frameworks Derived Porous Carbon for Absorption-Dominated Electromagnetic Interference Shielding [J]. Composites Part B: Engineering, 2022, 233: 109622.
[84] Zhang Y, Ruan K, Gu J. Flexible Sandwich-Structured Electromagnetic Interference Shielding Nanocomposite Films with Excellent Thermal Conductivities [J]. Small, 2021, 17(42): 2101951.
[85] Tang X-H, Li J, Wang Y, et al. Controlling Distribution of Multi-Walled Carbon Nanotube on Surface Area of Poly(Ε-Caprolactone) to Form Sandwiched Structure for High-Efficiency Electromagnetic Interference Shielding [J]. Composites Part B: Engineering, 2020, 196: 108121.
[86] Yang J, Liao X, Wang G, et al. Fabrication of Lightweight and Flexible Silicon Rubber Foams with Ultra-Efficient Electromagnetic Interference Shielding and Adjustable Low Reflectivity [J]. Journal of Materials Chemistry C, 2020, 8(1): 147-157.
[87] Xu Y, Yang Y, Yan D-X, et al. Gradient Structure Design of Flexible Waterborne Polyurethane Conductive Films for Ultraefficient Electromagnetic Shielding with Low Reflection Characteristic [J]. ACS Applied Materials & Interfaces, 2018, 10(22): 19143-19152.
[88] Sheng A, Ren W, Yang Y, et al. Multilayer WPU Conductive Composites with Controllable Electro-Magnetic Gradient for Absorption-Dominated Electromagnetic Interference Shielding [J]. Composites Part A: Applied Science and Manufacturing, 2020, 129: 105692.
[89] Liang C, Song P, Qiu H, et al. Constructing Interconnected Spherical Hollow Conductive Networks in Silver Platelets/Reduced Graphene Oxide Foam/Epoxy Nanocomposites for Superior Electromagnetic Interference Shielding Effectiveness [J]. Nanoscale, 2019, 11(46): 22590-22598.
[90] Rohini R, Bose S. Electromagnetic Interference Shielding Materials Derived from Gelation of Multiwall Carbon Nanotubes in Polystyrene/Poly(Methyl Methacrylate) Blends [J]. ACS Applied Materials & Interfaces, 2014, 6(14): 11302-11310.
[91] Kar G P, Biswas S, Rohini R, et al. Tailoring the Dispersion of Multiwall Carbon Nanotubes in Co-Continuous PVDF/ABS Blends to Design Materials with Enhanced Electromagnetic Interference Shielding [J]. Journal of Materials Chemistry A, 2015, 3(15): 7974-7985.
[92] Biswas S, Kar G P, Bose S. Tailor-Made Distribution of Nanoparticles in Blend Structure toward Outstanding Electromagnetic Interference Shielding [J]. ACS Applied Materials & Interfaces, 2015, 7(45): 25448-25463.
[93] Yang J, Yang Y, Duan H, et al. Light-Weight Epoxy/Nickel Coated Carbon Fibers Conductive Foams for Electromagnetic Interference Shielding [J]. Journal of Materials Science: Materials in Electronics, 2017, 28(8): 5925-5930.
[94] Zhang H, Zhang G, Tang M, et al. Synergistic Effect of Carbon Nanotube and Graphene Nanoplates on the Mechanical, Electrical and Electromagnetic Interference Shielding Properties of Polymer Composites and Polymer Composite Foams [J]. Chemical Engineering Journal, 2018, 353: 381-393.
[95] Zeng Z, Wu T, Han D, et al. Ultralight, Flexible, and Biomimetic Nanocellulose/Silver Nanowire Aerogels for Electromagnetic Interference Shielding [J]. ACS Nano, 2020, 14(3): 2927-2938.
[96] Yu Z, Dai T, Yuan S, et al. Electromagnetic Interference Shielding Performance of Anisotropic Polyimide/Graphene Composite Aerogels [J]. ACS Applied Materials & Interfaces, 2020, 12(27): 30990-31001.
[97] Shen Y, Lin Z, Liu X, et al. Robust and Flexible Silver-Embedded Elastomeric Polymer/Carbon Black Foams with Outstanding Electromagnetic Interference Shielding Performance [J]. Composites Science and Technology, 2021, 213: 108942.
[98] Liang C, Liu Y, Ruan Y, et al. Multifunctional Sponges with Flexible Motion Sensing and Outstanding Thermal Insulation for Superior Electromagnetic Interference Shielding [J]. Composites Part A: Applied Science and Manufacturing, 2020, 139: 106143.
[99] Shao T, Wu J, Zhang Y, et al. Highly Sensitive Conformal Pressure Sensing Coatings Based on Thermally Expandable Microspheres [J]. Advanced Materials Technologies, 2020, 5(5): 2000032.
[100] Aglan H, Shebl S, Morsy M, et al. Strength and Toughness Improvement of Cement Binders Using Expandable Thermoplastic Microspheres [J]. Construction and Building Materials, 2009, 23(8): 2856-2861.
[101] Kawaguchi Y, Oishi T. Synthesis and Properties of Thermoplastic Expandable Microspheres: The Relation between Crosslinking Density and Expandable Property [J]. Journal of Applied Polymer Science, 2004, 93(2): 505-512.
[102] Jiao S-Z, Sun Z-C, Li F-R, et al. Preparation and Application of Conductive Polyaniline-Coated Thermally Expandable Microspheres [J]. 2019, 11(1): 22.
[103] Jonsson M, Nordin O, Kron A L, et al. Thermally Expandable Microspheres with Excellent Expansion Characteristics at High Temperature [J]. Journal of Applied Polymer Science, 2010, 117(1): 384-392.
[104] Li F, Zhang Q, Jiao S, et al. Preparation, Characterization and Foaming Performance of Thermally Expandable Microspheres [J]. Materials Research Express, 2020, 7(11): 115302.
[105] Yi Q, Li J, Zhang R, et al. Preparation of Small Particle Diameter Thermally Expandable Microspheres under Atmospheric Pressure for Potential Utilization in Wood [J]. Journal of Applied Polymer Science, 2021, 138(4): 49734.
[106] Safajou-Jahankhanemlou M, Abbasi F, Salami-Kalajahi M. Synthesis and Characterization of Thermally Expandable PMMA-Based Microcapsules with Different Cross-Linking Density [J]. Colloid and Polymer Science, 2016, 294(6): 1055-1064.
[107] Hu L, Wang J, Qin L, et al. Foaming Performance and Bonding Strength of a Novel Urea-Formaldehyde Foaming Resin Facilely Prepared with Thermo-Expandable Microspheres [J]. International Journal of Adhesion and Adhesives, 2021, 105: 102783.
[108] Cai J-H, Li J, Chen X-D, et al. Multifunctional Polydimethylsiloxane Foam with Multi-Walled Carbon Nanotube and Thermo-Expandable Microsphere for Temperature Sensing, Microwave Shielding and Piezoresistive Sensor [J]. Chemical Engineering Journal, 2020, 393: 124805.
[109] Petrossian G, Hohimer C J, Ameli A. Highly-Loaded Thermoplastic Polyurethane/Lead Zirconate Titanate Composite Foams with Low Permittivity Fabricated Using Expandable Microspheres [J]. 2019, 11(2): 280.
[110] Andersson H, Örtegren J, Zhang R, et al. Variable Low-Density Polylactic Acid and Microsphere Composite Material for Additive Manufacturing [J]. Additive Manufacturing, 2021, 40: 101925.
[111] Jiao S, Sun Z, Zhou Y, et al. Surface-Coated Thermally Expandable Microspheres with a Composite of Polydisperse Graphene Oxide Sheets [J]. Chemistry – An Asian Journal, 2019, 14(23): 4328-4336.
[112] Jonsson M, Nyström D, Nordin O, et al. Surface Modification of Thermally Expandable Microspheres by Grafting Poly(Glycidyl Methacrylate) Using Arget Atrp [J]. European Polymer Journal, 2009, 45(8): 2374-2382.
[113] Xue B, Zhang J, Bao Y. Acoustically and Thermally Insulating Epoxy Foams Prepared by Non-Traditional Expandable Microspheres [J]. Polymer Engineering and Science, 2019, 59(4): 799-806.
[114] Liang X, Zhao T, Hu Y, et al. CuCl2 and Stainless Steel Synergistically Assisted Synthesis of High-Purity Silver Nanowires on a Large Scale [J]. RSC Advances, 2014, 4(88): 47536-47539.
[115] Shuai X, Zhu P, Zeng W, et al. Highly Sensitive Flexible Pressure Sensor Based on Silver Nanowires-Embedded Polydimethylsiloxane Electrode with Microarray Structure [J]. ACS Applied Materials & Interfaces, 2017, 9(31): 26314-26324.
[116] Zhan Y, Cheng Y, Yan N, et al. Lightweight and Self-Healing Carbon Nanotube/Acrylic Copolymer Foams: Toward the Simultaneous Enhancement of Electromagnetic Interference Shielding and Thermal Insulation [J]. Chemical Engineering Journal, 2021, 417: 129339.
[117] Guo F, Jiang Y, Xu Z, et al. Highly Stretchable Carbon Aerogels [J]. Nature Communications, 2018, 9(1): 881.
[118] Hu X, He R, Huang Y, et al. A Method to Predict the Dynamical Behaviors of Carbon Black Filled Natural Rubber at Different Temperatures [J]. Polymer Testing, 2019, 79: 106067.
[119] Zhang K, Li G-H, Feng L-M, et al. Ultralow Percolation Threshold and Enhanced Electromagnetic Interference Shielding in Poly(L-Lactide)/Multi-Walled Carbon Nanotube Nanocomposites with Electrically Conductive Segregated Networks [J]. Journal of Materials Chemistry C, 2017, 5(36): 9359-9369.
[120] Gao H-L, Zhu Y-B, Mao L-B, et al. Super-Elastic and Fatigue Resistant Carbon Material with Lamellar Multi-Arch Microstructure [J]. Nature Communications, 2016, 7(1): 12920.
[121] Shen B, Li Y, Yi D, et al. Microcellular Graphene Foam for Improved Broadband Electromagnetic Interference Shielding [J]. Carbon, 2016, 102: 154-160.
[122] Chen J, Liao X, Xiao W, et al. Facile and Green Method to Structure Ultralow-Threshold and Lightweight Polystyrene/MWCNT Composites with Segregated Conductive Networks for Efficient Electromagnetic Interference Shielding [J]. ACS Sustainable Chemistry & Engineering, 2019, 7(11): 9904-9915.
[123] Hamidinejad M, Zhao B, Zandieh A, et al. Enhanced Electrical and Electromagnetic Interference Shielding Properties of Polymer–Graphene Nanoplatelet Composites Fabricated Via Supercritical-Fluid Treatment and Physical Foaming [J]. ACS Applied Materials & Interfaces, 2018, 10(36): 30752-30761.
[124] Ameli A, Nofar M, Wang S, et al. Lightweight Polypropylene/Stainless-Steel Fiber Composite Foams with Low Percolation for Efficient Electromagnetic Interference Shielding [J]. ACS Applied Materials & Interfaces, 2014, 6(14): 11091-11100.
[125] Wang H, Zheng K, Zhang X, et al. 3D Network Porous Polymeric Composites with Outstanding Electromagnetic Interference Shielding [J]. Composites Science and Technology, 2016, 125: 22-29.
[126] Wang G, Zhao G, Wang S, et al. Injection-Molded Microcellular PLA/Graphite Nanocomposites with Dramatically Enhanced Mechanical and Electrical Properties for Ultra-Efficient EMI Shielding Applications [J]. Journal of Materials Chemistry C, 2018, 6(25): 6847-6859.
[127] Ding L, Ding Z Y, Wei X C. Shielding Effectiveness Measurement of SIP Based on Near-Field Scanning [C]. Proceedings of the 2019 IEEE International Conference on Integrated Circuits, Technologies and Applications (ICTA), 2019, 136-137.
[128] Shen Y, Lin Z, Wei J, et al. Facile Synthesis of Ultra-Lightweight Silver/Reduced Graphene Oxide (RGO) Coated Carbonized-Melamine Foams with High Electromagnetic Interference Shielding Effectiveness and High Absorption Coefficient [J]. Carbon, 2022, 186: 9-18.
[129] Jia H, Yang X, Kong Q-Q, et al. Free-Standing, Anti-Corrosion, Super Flexible Graphene Oxide/Silver Nanowire Thin Films for Ultra-Wideband Electromagnetic Interference Shielding [J]. Journal of Materials Chemistry A, 2021, 9(2): 1180-1191.
[130] Chen Y, Pang L, Li Y, et al. Ultra-Thin and Highly Flexible Cellulose Nanofiber/Silver Nanowire Conductive Paper for Effective Electromagnetic Interference Shielding [J]. Composites Part A: Applied Science and Manufacturing, 2020, 135: 105960.
[131] Fu B, Ren P, Guo Z, et al. Construction of Three-Dimensional Interconnected Graphene Nanosheet Network in Thermoplastic Polyurethane with Highly Efficient Electromagnetic Interference Shielding [J]. Composites Part B: Engineering, 2021, 215: 108813.
[132] Yang J, Liao X, Li J, et al. Light-Weight and Flexible Silicone Rubber/MWCNTs/Fe3O4 Nanocomposite Foams for Efficient Electromagnetic Interference Shielding and Microwave Absorption [J]. Composites Science and Technology, 2019, 181: 107670.
[133] Yu W-C, Wang T, Liu Y-H, et al. Superior and Highly Absorbed Electromagnetic Interference Shielding Performance Achieved by Designing the Reflection-Absorption-Integrated Shielding Compartment with Conductive Wall and Lossy Core [J]. Chemical Engineering Journal, 2020, 393: 124644.
[134] Yang Y, Chen S, Li W, et al. Reduced Graphene Oxide Conformally Wrapped Silver Nanowire Networks for Flexible Transparent Heating and Electromagnetic Interference Shielding [J]. ACS Nano, 2020, 14(7): 8754-8765.
[135] Zhang L-Q, Yang S-G, Li L, et al. Ultralight Cellulose Porous Composites with Manipulated Porous Structure and Carbon Nanotube Distribution for Promising Electromagnetic Interference Shielding [J]. ACS Applied Materials & Interfaces, 2018, 10(46): 40156-40167.
[136] Cui C-H, Yan D-X, Pang H, et al. A High Heat-Resistance Bioplastic Foam with Efficient Electromagnetic Interference Shielding [J]. Chemical Engineering Journal, 2017, 323: 29-36.
[137] Kong L, Yin X, Han M, et al. Macroscopic Bioinspired Graphene Sponge Modified with In-Situ Grown Carbon Nanowires and Its Electromagnetic Properties [J]. Carbon, 2017, 111: 94-102.
[138] Ameli A, Jung P U, Park C B. Electrical Properties and Electromagnetic Interference Shielding Effectiveness of Polypropylene/Carbon Fiber Composite Foams [J]. Carbon, 2013, 60: 379-391.
[139] Guo T, Chen X, Su L, et al. Stretched Graphene Nanosheets Formed the “Obstacle Walls” in Melamine Sponge Towards Effective Electromagnetic Interference Shielding Applications [J]. Materials & Design, 2019, 182: 108029.
[140] Shen B, Li Y, Zhai W, et al. Compressible Graphene-Coated Polymer Foams with Ultralow Density for Adjustable Electromagnetic Interference (EMI) Shielding [J]. ACS Applied Materials & Interfaces, 2016, 8(12): 8050-8057.
[141] Kuang T, Chang L, Chen F, et al. Facile Preparation of Lightweight High-Strength Biodegradable Polymer/Multi-Walled Carbon Nanotubes Nanocomposite Foams for Electromagnetic Interference Shielding [J]. Carbon, 2016, 105: 305-313.
[142] Xu H, Yin X, Li X, et al. Lightweight Ti3C2Tx MXene/Poly(Vinyl Alcohol) Composite Foams for Electromagnetic Wave Shielding with Absorption-Dominated Feature [J]. ACS Applied Materials & Interfaces, 2019, 11(10): 10198-10207.
[143] Zhu S, Zhou Q, Wang M, et al. Modulating Electromagnetic Interference Shielding Performance of Ultra-Lightweight Composite Foams through Shape Memory Function [J]. Composites Part B: Engineering, 2021, 204: 108497.
[144] Lee T-W, Lee S-E, Jeong Y G. Highly Effective Electromagnetic Interference Shielding Materials Based on Silver Nanowire/Cellulose Papers [J]. ACS Applied Materials & Interfaces, 2016, 8(20): 13123-13132.
[145] Thomassin J-M, Jérôme C, Pardoen T, et al. Polymer/Carbon Based Composites as Electromagnetic Interference (EMI) Shielding Materials [J]. Materials Science and Engineering: R: Reports, 2013, 74(7): 211-232.
[146] Liu X, Li Y, Sun X, et al. Off/on Switchable Smart Electromagnetic Interference Shielding Aerogel [J]. Matter, 2021, 4(5): 1735-1747.
[147] Wan Y-J, Zhu P-L, Yu S-H, et al. Anticorrosive, Ultralight, and Flexible Carbon-Wrapped Metallic Nanowire Hybrid Sponges for Highly Efficient Electromagnetic Interference Shielding [J]. Small, 2018, 14(27): 1800534.
[148] Liao S-Y, Wang X-Y, Li X-M, et al. Flexible Liquid Metal/Cellulose Nanofiber Composites Film with Excellent Thermal Reliability for Highly Efficient and Broadband EMI Shielding [J]. Chemical Engineering Journal, 2021, 422: 129962.
[149] Kim D G, Choi J H, Choi D-K, et al. Highly Bendable and Durable Transparent Electromagnetic Interference Shielding Film Prepared by Wet Sintering of Silver Nanowires [J]. ACS Applied Materials & Interfaces, 2018, 10(35): 29730-29740.
[150] Zeng Z, Jiang F, Yue Y, et al. Flexible and Ultrathin Waterproof Cellular Membranes Based on High-Conjunction Metal-Wrapped Polymer Nanofibers for Electromagnetic Interference Shielding [J]. Advanced Materials, 2020, 32(19): 1908496.