前处理方式对壳核型Ag/SiO_(2)电磁屏蔽涂层的影响  

Effects of Pretreatment Method on Ag/SiO_(2) Core-Shell Electromagnetic Shielding Coating

作　　者：闫家琦 苏晓磊 刘毅 YAN Jia-qi;SU Xiao-lei;LIU Yi(School of Materials Science&Engineering,Xi’an Polytechnic University,Xi’an 710048,China)

机构地区：[1]西安工程大学材料工程学院,西安710048

出　　处：《表面技术》2021年第10期169-176,共8页Surface Technology

基　　金：陕西省重点研发计划项目(2020GY-035);陕西省自然科学基础研究计划项目(2019JQ-853);西安市科技计划项目(2019217114GXRC001CG0098-GXYD7.6)。

摘　　要：目的制备镀层密实均匀、不易脱落、与树脂结合性好的壳核型Ag/SiO_(2)导电粉体,以获得性能优异的Ag/SiO_(2)电磁屏蔽涂层。方法分别使用敏化、偶联剂改性、高分子表面包覆前处理方式,以葡萄糖作还原剂,氨水作Ag+络合剂,进行化学镀银,制备Ag/SiO_(2)微珠。测试了复合粉体的导电性能,并结合试验现象,分析了前处理反应机理和银层生长机理。采用扫描电子显微镜和X射线衍射仪,对不同前处理方式的Ag/SiO_(2)微珠结构进行表征与验证。用不同前处理方式制备的Ag/SiO_(2)微珠为填料,不饱和聚酯树脂为基体,制备导电涂层,研究不同Ag/SiO_(2)微珠与涂层的结合性能以及填料含量对涂层导电性能的影响。结果采用敏化前处理法所制备的Ag/SiO_(2)微珠银层均匀、密实、无脱落,明显优于其他两种前处理方式,其压实电阻可低至144.04 mΩ,并且Ag/SiO_(2)微珠填料添加量在80%时,可形成最优的导电通路,体积电阻率低至0.0051Ω·cm,电磁波频率8.2~12.4 GHz下的电磁屏蔽效能可达到51.9 dB。结论采用敏化法前处理玻璃微珠表面可镀覆出质量优异的银层,且在树脂体系中导电性能好,可作为优质的电磁屏蔽剂制备导电涂层。In order to prepare Ag/SiO_(2) conductive powder with dense and uniform coating,which is not easy to fall off and has good binding ability with resin,Ag/SiO_(2) electromagnetic shielding coating with excellent performance can be obtained.Pretreatment with sensitizer,coupling agent modification,and polymer surface coating respectively.Use glucose as reducing agent and ammonia water as Ag^(+)complexing agent for electroless silver plating to prepare Ag/SiO_(2) microbeads.The electrical conductivity of the composite powder was tested,and the reaction mechanism of the pretreatment and the growth mechanism of the silver layer were analyzed based on experimental phenomena.Scanning electron microscope and X-ray diffractometer were used to characterize and verify Ag/SiO_(2) microbeads with different pretreatment methods.The Ag/SiO_(2) microbeads prepared by different pretreatment methods are used as fillers,unsaturated polyester resin is used as the matrix to prepare conductive coatings,and the bonding properties of different Ag/SiO_(2) microbeads and coatings and the effects of filler content on the conductivity of the coatings are studied.The results found that the silver layer of Ag/SiO_(2) microbeads prepared by the sensitization pretreatment method is uniform,dense,and no shedding,which is significantly better than the other two pretreatment methods.The compaction resistance can be as low as 144.04 mΩ,and the Ag/SiO_(2) microbeads when the filler content is 80%,the optimal conductive path can be formed,the volume resistivity can be as low as 0.0051Ω·cm,and the electromagnetic shielding efficiency can reach 51.9 dB when the electromagnetic wave frequency is 8.2~12.4 GHz.It is concluded that the sensitization method can be used to plate the surface of the glass beads with a high-quality silver layer,which has good electrical conductivity in the resin system.It can be used as a high-quality electromagnetic shielding agent for the preparation of conductive coatings.The prepared electromagnetic shielding coating has e

关 键 词：镀银玻璃微珠 导电粉体 不饱和聚酯树脂 导电涂层 体积电阻率 电磁屏蔽 

分 类 号：TQ153[化学工程—电化学工业]