碳基复合导电浆料改性研究

导电浆料目前在电子产品中得到广泛的应用,是电子信息产业发展不可或缺的关键辅材。该文针对国内硅胶按键用导电浆料的研发需求,设计一种碳基掺金属/非金属粉末的导电浆料,以炭黑掺银粉作为主要的导电相,煤油作为溶剂,聚乙烯吡咯烷酮作为保护剂,二氧化硅作为填充改性剂,控制不同组分的含量和配比,得到碳基复合导电浆料。采用光学显微镜、四探针测试仪、扫描电镜、EDS、洛氏硬度计、百格刀等手段对固化后的导电浆料进行光学、电学、形貌、组分、强度及附着力等性质测试,分析金属导电相和无机非金属填充相的加入对导电浆料性能的影响。综合各种因素,最终得到改进附着力(4B等级)、导电性(6Ω·cm)和机械强度(185 Hv0.5),适用于硅胶按键的低成本碳基复合导电浆料,其基体/银粉/二氧化硅比例约为100∶5∶1。

Conductive paste currently widely used in electronic products is an indispensable key auxiliary material for the development of the electronic information industry. In view of the research and development needs of domestic conductive paste for silicone keys, a carbon-based conductive paste mixed with metal/non-metal powder was fabricated in this work. Carbon black mixed silver powder was used as the main conductive phase, kerosene was used as solvent,polyethylene pyrrolidone was used as a protective agent, and silica was added to improve the mechanical strength and thermal conductivity, and the content and ratio of different components were controlled to obtain a carbon-based conductive paste. The effects of the addition of metal conductive phase and inorganic non-metallic filling phase on the properties of conductive paste were analyzed by Optical microscope, Four-point probe tester, Scanning electron microscope, EDS, Rockwell hardness tester, Cross-cut tester and other methods. As a result, a low-cost carbon-based conductive paste suitable for silicone keys with improved properties, such as adhesion(4B grade), electrical conductivity(6 Ω·cm) and mechanical strength(185 Hv0.5), was finally achieved, with the ratio of matrix/silver powder/silica being about 100∶5∶1.