有机硅叠瓦导电胶性能研究

Study on performance of silicone laminated conductive adhesive

通过自制有机硅胶粘剂与银粉复配制备了有机硅导电胶粘剂,采用显微镜观察固化后表面气泡,并研究了不同银含量、固化温度、固化时间以及不同银粉比例对导电胶体积电阻率及粘接性能的影响。研究结果表明:在w(银粉)=77%(相对于导电胶总质量而言)、固化温度160℃、固化时间30 min、m(类球状银粉)∶m(片状银粉)=8∶2的条件下,体积电阻率、固化强度均达到较佳值,分别为1.3×10^(-4)Ω·cm和258.6 N。对导电机理进行了简单分析,类球状银粉与片状银粉间存在有效搭接,电子可通过界面接触和隧道效应通过银粉表面,形成导电网络,导电性能得以提高。

Organic silicone conductive adhesive was prepared by compounding the self-made organic silicone adhesive with silver powder. The surface bubbles after curing were observed by microscope,and the effects of different silver content,curing temperature,curing time and different silver powder ratios on the volume resistivity and bonding performance of conductive adhesive were studied. The research results showed that,under the conditions of w(silver powder)=77%(relative to the total mass of conductive adhesive),curing temperature was160 ℃,curing time was 30 min,m(spherical silver powder)∶m(flaky silver powder)=8∶2,the volume resistivity and curing strength reached relatively good values,which were 1.3×10^(-4)Ω ·cm and 258.6 N respectively. The conductive mechanism was simply analyzed. There was an effective overlap between spherical silver powder and flaky silver powder. Electrons could pass through the surface of silver powder by means of interface contact and tunneling effect to form a conductive network,and the conductivity could be improved.