石墨烯泡沫应用于宽屏电磁波屏蔽PPT file Wentao Zhai

1、1Microcellular graphene foam for improved broadband electromagnetic interference shielding石墨烯泡沫应用于宽屏电磁波屏蔽石墨烯泡沫应用于宽屏电磁波屏蔽Wentao Zhai翟文涛翟文涛Ningbo Institute, CAS中科院宁波材料所中科院宁波材料所20161018Our research interests我们的研究兴趣我们的研究兴趣Development of extrusion foaming technology开发连续挤出发泡技术开发连续挤出发泡技术 Extrusion foaming

2、system with using CO2 as the blowing agent; 以超临界CO2流体为发泡剂 Regular PP was used to produce PP foam 通用PP用作发泡体系Development of autoclave foaming technology开发釜压发泡技术开发釜压发泡技术EPPEPPEPLAEPIETPUOur research interests我们的研究兴趣我们的研究兴趣4Development of multi-functional polymer foam film开发多功能聚合物发泡薄膜开发多功能聚合物发泡薄膜 Polyme

3、r/filler/DMFPrecipitationDryingRedissolving Water vapor induced phase separationWater vaporH2OSolution blendingPolymer nanocompositePolymer foam filmDryingFilm casting Our research interests我们的研究兴趣我们的研究兴趣5Advantages of (microcellar) foaming微发泡的优势微发泡的优势 lightweight/轻量化轻量化; Thermal insulation/隔热隔热; So

4、und insulation/隔音；隔音； Improved impact/cushion properties/提高提高了冲击了冲击/缓冲性能；缓冲性能； Reduced dielectric properties/降低了介电性能降低了介电性能 Absorbing the microwave as a maze structure; 为电磁波提供迷宫结构；为电磁波提供迷宫结构；EMI shielding materials电磁屏蔽材料电磁屏蔽材料Advantages of (microcellar) foaming微发泡的优势微发泡的优势EM interference effects 电磁干

5、扰电磁干扰 Compromise the performance and lifetime of devises Interfere with the function of other nearby components EM information leakage 电磁泄露电磁泄露Computer, cell phone,To damage the human body 危害人体危害人体Harmful effects of EM wave电磁波的危害电磁波的危害8Radar detection雷达探测雷达探测Electromagnetic stealth materialsRadar de

6、tection: Broad band EM wavetransmitted or received by radarClassical protection against EMIMetal sheetsBut: high density Poor mechanical flexibility Corrosion Limited tuning of the shielding effectiveness (SE)Advantages brought by polymersEasy shapingLightweightLow costBut most polymers are transpar

7、ent to the EMI waveMethods to improve the EMI SE of polymersTo disperse electrically conductive fillers in polymer matrixThe carbon materials such as carbon black, graphite, carbon nanotube, graphene nanosheets are usually selected as the conductive fillers.Classical materials for EMI shielding经典的电磁

8、屏蔽材料经典的电磁屏蔽材料Novel cellular structure of polymer composites for EMI shieldingPolymer/conductive filler compositePolymer/conductive filler composite foam金属材料的电磁屏蔽机制为反射损耗；金属材料的电磁屏蔽机制为反射损耗；聚合物复合材料以反射损耗为主；聚合物复合材料以反射损耗为主；均易导致电磁波二次污染问题。均易导致电磁波二次污染问题。 入射波能量入射波能量 反射波能量反射波能量透射波能量透射波能量聚合物发泡材料以吸收损耗为主，有效聚合物发泡材料

9、以吸收损耗为主，有效避免电磁波的二次污染问题避免电磁波的二次污染问题透射波能量透射波能量入射波能量入射波能量反射波能量反射波能量Tendency of EMI shielding materials电磁屏蔽材料发展趋势电磁屏蔽材料发展趋势Lighter/轻量化轻量化Thinner/更薄更薄Higher EMI SE/更高的屏蔽效能更高的屏蔽效能For the application in special fields such as aerospace, weapon equipment, microelectrionics.Superior thermal stability/耐高温耐高温F

10、lame retardancy/阻燃阻燃Excellent mechanical properties/有益的性能有益的性能Flexible/柔性柔性High Tg: 220 C;Flame retardant;Solid stat foaming using compressed CO2 as the physical blowing agentPreparation of high performance PEI microcellular foam 制备高性能制备高性能PEI微发泡材料微发泡材料Miller, D. et al., Polymer, 2011, 52, 2910.Publ

11、ished data of microcellular high performance foam/发表的高性能聚合物发泡材料论文发表的高性能聚合物发泡材料论文Expansion ratio lower than 5 times膨胀倍率低于膨胀倍率低于5倍倍Method to improve the expansion ratio of PI microcellular foam/提高膨胀倍率的方法提高膨胀倍率的方法Density：90 kg/m3Expansion rate: 15timesW.T. Zhai*, W.W. Feng, J.Q. Ling, W.G. Zheng, Ind.

12、Eng. Chem. Res., 2012, 51, 12827. THF as a co-blowing agentTg: 265 C50 mCell size：2030 mCell morphology of microcellular PI bead foam PEI微发泡粒子的泡孔形态微发泡粒子的泡孔形态Compression molding of PI bead foam模压粘结成型模压粘结成型Tg:230 C, 50 times expansion/50倍膨胀倍膨胀;翟文涛，郑文革，凌建强，中国发明专利， 201210171721.X翟文涛，郑文革，冯卫卫，凌建强，中国发明专利，

13、201210170254.9PI microcellular foam with superhigh volume expansion/制备超高倍率制备超高倍率PI泡沫泡沫Compression molding模压成型模压成型 High processing temperature up to 320-360 C/加工加工温度高达温度高达320-360度度； High viscosity of composite melt and difficult to disperse high content of nanofillers/体系粘度高，难以分散体系粘度高，难以分散; Difficult

14、to achieve a high foam expansion ratio/难以难以得到高的膨胀倍率；得到高的膨胀倍率； A high filler content requirement to achieve a good EMI shielding properties/优异的屏蔽效能需要添加高含量的吸优异的屏蔽效能需要添加高含量的吸收剂！收剂！Challenging in the preparation of PI composite foam with high filler loading 制备高填充制备高填充PI复合材料泡沫的挑战复合材料泡沫的挑战20Polymer/filler

15、/DMFPrecipitationDryingRedissolving Water vapor induced phase separationWater vaporH2OSolution blendingPolymer nanocompositePolymer foam filmDryingFilm casting Method to solve the challenging/解决办法解决办法Preparation of PEI/graphene microcellular foam/制备制备PEI/石墨烯发泡材料石墨烯发泡材料J.Q. Ling, W.T. Zhai*, W.W. Fen

16、g. et al., ACS Appl. Mater. Interfaces, 2013, 5, 2677.B. Shen, D.D. Lu, W.T. Zhai*, et al., ACS Appl. Mater. Interfaces, 2013, 5, 11383.PEI/Graphene/DMF solutionSample size: 2.3 mm22EMI SE test/电磁屏蔽效能测试电磁屏蔽效能测试R&S ZVA67 vestor network analyzer 网络分析仪 Sample size: 22.5 mm 10.0 mmFoaming: Volume expans

17、ion of 5 timesFor the commercial usage 20dB商用电磁屏蔽材料商用电磁屏蔽材料需要效能大于需要效能大于20dBPEI/graphene microcellular foam used for EMI shielding/电磁屏蔽效能电磁屏蔽效能24Preparation of high thermal stable PI/graphene microcellular foam/制备泡沫制备泡沫The improved dispersion of graphene oxide by in-situ polymerization通过原位聚合来改善氧化石墨通过

18、原位聚合来改善氧化石墨烯的分散烯的分散Y. Li, W.T. Zhai*, et al., RSC Adv., 2015, 5, 24342.25Thermal imidization at 350 C350度亚胺化Cell morphology of PAA/graphane and PI/graphene microcellular foams/泡孔形态泡孔形态Samples with the thickness of 0.8 mm样品厚度仅为样品厚度仅为0.8毫米毫米 EMI SE of PI/graphene microcellular foam/PI/石墨烯泡沫的电磁屏蔽效能石墨烯泡

19、沫的电磁屏蔽效能16 wt % rGO27PMDA/ODA/GO/DMFCarbonization and graphitizationImidizationCasting on glass substrateIn situ polymerizationPhase separationMicrocellular PI/graphene foamsCarbon/graphene foamGraphite plateN2 atmospherePAA/GO casting solutionCoagulant bathPreparation of carbon/graphene microcellul

20、ar foam/制备石墨烯制备石墨烯/碳泡沫碳泡沫Y. Li, W.T. Zhai*, et al., Carbon, 2016, 100, 375-385.350 C1000 C1500 C2100 C2600 C2600 C5 m5 m5 m5 m5 m1 m10203040506070802600 C2100 C1500 C1000 C(004)(100) (002)350 C Intensity (a.u.)2 100015002000250030002600 CID/IG= 0.429ID/IG= 0.814ID/IG= 2.207ID/IG= 1.425ID/IG= 1.972G-

21、bandD-bandG-bandD-band350 C1000 C1500 C Intensity (a.u.)Raman shift (cm-1)2100 CPI (350C) Carbonization (1000-1500C) Graphitization (2100-2600 C) Cell morphology evolution during the pyrolysis/碳化碳化/石墨化过程中泡孔结构的演变石墨化过程中泡孔结构的演变EMI SE of carbon/graphene microcellular foam/石墨烯石墨烯/碳复合泡沫的屏蔽效能碳复合泡沫的屏蔽效能Prep

22、aration of graphene film by direct evaporation of GO suspension/GO薄膜薄膜 self-assembly of GO into the GO film 自组装成自组装成GO薄膜；薄膜； GO was thermal reduction into graphene film； 热还原成石墨烯薄膜热还原成石墨烯薄膜B. Shen, W.T. Zhai*, W.G. Zheng*, Advanced Functional Materials, 2014, 24, 4542.Proofs of the thermal reduction of graphene oxide into graphene/热还原的证据热还原的证据Conductivity of GO and grpahene电导率电导率sp3 Csp2 CThe EMI SE of GO and graphene屏蔽效能屏蔽效能 B. Shen, W.T. Zhai* et al., Carbon, 2016, 102,154.Preparation of graphene foam by the hydrazine foaming/水合肼发