喷墨打印金属复合结构精细制备可拉伸电路研究

The stretchable circuit plays a key role in enhancing the application performance of electronic devices. However, it is difficult to realize the precise preparation of stretchable circuit based on traditional etching and direct printing. In this project, stretchable circuit is precisely presented by inkjet printing technology. Precured liquid elastomeric prepolymer mixed with a reducing agent is served as the printing substrate. Conductive precursor in aqueous solution is used as a water-based inkjet ink. Then an oil-water interface redox reaction system is carried out to generate pattern by inkjet printing. Adding surfactants in aqueous inks, micro-ultrasound is studied to achieve an oil-in-water emulsion transition layer between the oil phase and the water phase. Furtherly, regulating and controlling the oil-water interface reaction in the emulsified layer, after the substrate is cured, a metal composite structure is formed in the inkjet printing area. It is composed of a continuous metal layer encapsulated elastic polymer, which will effectively improve the stretchable properties of the circuit. In this project, forming process and mechanism of an oil-in-water emulsified layer is studied in inkjet printed oil-water interface system. Metal composite structure is formed by an oil-water interface reaction. This method could precisely prepare stretchable circuits. It is of great significance for the manufacture of flexible stretchable electronic devices.

可拉伸电路对于增强电子器件的应用性能起着关键作用，但是，基于传统蚀刻、直接印刷等方法难以实现可拉伸电路的精细制备。本项目拟利用喷墨打印金属复合结构精细制备可拉伸电路，将预固化的液态弹性预聚物与还原剂混合作为油性还原基底，导电前驱体水性溶液作为水性喷墨墨水，通过喷墨打印构建图案化的油水界面氧化还原反应体系。利用在水相墨水中添加表面活性剂，微超声施加油水界面处的机械剪切作用，对油水界面处形成水包油乳化层的过程及机理进行研究。进一步，调控乳化层中的油水界面反应，在基底固化后，喷墨打印区域会形成一层金属复合结构，该结构由油水界面反应生成的连续金属层包裹固化的弹性聚合物构成，这将有效提高喷墨打印电路的可拉伸性能。本项目对喷墨打印的油水界面体系形成水包油乳化层的过程及机理进行了研究，利用油水界面反应形成了金属复合结构，从而实现了可拉伸电路的精细制备，对于柔性可拉伸电子器件制造具有重要意义。

液液界面浸润研究对于可控沉积制备新材料具有重要意义，液液界面反应可以有效形成高强度复合材料结构，有助于印刷柔性电子领域技术发展应用。基于油水界面反应通过喷墨打印技术精细制备了可弯折电路。银氨离子水溶液作为喷墨打印墨水，液态的聚二甲基硅氧烷（PDMS）添加还原剂作为印刷的基材，利用喷墨打印技术构筑了油水界面图案。从而将一种油水界面反应过程用于产生银电路。研究结果表明当添加少量表面活性剂后，水相能够很好的润湿油相进而产生一层厚实致密的银层。在PDMS表面上形成的嵌入式结构的厚度达到15-20微米。嵌入式结构极大地提升了喷墨打印电路可弯折性能。进一步，利用浸润界面墨滴沉积行为间距控制，实现了高精度电路制备；利用浸润界面墨滴沉积行为微结构压印控制，实现了高灵敏传感器制备；利用浸润界面墨滴沉积行为复合结构控制，实现了柔性高比表面积电化学电极制备。基于本项目研究工作，形成了界面润湿反应理论研究基础及可控复合结构制备及应用。在本项目支持下，发表第一作者或通讯作者SCI论文共计7篇，包括ACS applied materials & interfaces、Applied Surface Science、Langmuir及Materials Letters等；第一发明人申请国家发明专利5件，其中已授权国家发明专利2件。