交变电场诱导溶液流变与射流喷印调控机制研究

Thanks to the excellent advantages, Electrohydrodynamic Direct-Writing (EDW) has displayed great potential in the fields of flexible micro/nano system. This project introduces alternating electric field to change charge migration characters, reduce the distributions and increase the stability of EDW jet injection. The key issues of stable injection and precise position of conductive jet on insulate polymeric substrate can be realized. This project focuses on a series of basic scientific problems on the regulation mechanism of solution rheology and jet printing under the induction of alternating electric field. The main research contents are as follows: the charge distribution and migration characters in viscoelastic conductive solution under the alternating electric field; rheology behaviors and boundary layer evolution processes of viscoelastic conductive solution; the influences of process parameters on the frequency and wavelength in the surface waving of conductive solution; the critical conditions of conductive jet injection would be investigated to gain the controlling law of fast start & stop controlling; force analysis is done to study the motion and rheology behaviors of conductive jet; the motion and deposition behaviors of conductive jet on the insulate polymeric substrate are investigated to build up the controlling strategies of precise position for conductive jet; conductive micro/nano structures are direct-written precisely on the insulate substrate to construct micro pattern, and then organic micro sensing device can be fabricated. This project would advance the accurate regulation of conductive jet on insulate substrate, and accelerate the industrial application of EDW technology.

以其独特优势，电纺直写已在柔性微纳系统制造中表现出巨大发展潜力。项目引入交变电场，改变电荷分布迁移特性、减小干扰提高射流稳定性，以突破导电溶液在绝缘基底上单射流稳定喷射和精确定位沉积两个关键问题；并将围绕交变电场诱导溶液流变与射流喷印调控机制等一类基础科学问题展开研究，主要研究内容：分析交变电场诱导作用下导电溶液的电荷分布规律和迁移行为，讨论导电溶液流变特性和边界层演变机制；研究导电溶液表面波动特性，分析工艺参数对波动频率、波长的影响规律；研究导电单射流启动、喷射、停止的临界条件和控制规律，实现导电单射流快速启停控制；分析导电射流受力变化规律，研究导电射流运动行为和流变机制；讨论导电射流在有机绝缘基底上的运动、沉积行为，掌握其精确定位沉积控制策略；实现导电功能性微纳结构在绝缘基底的定位沉积和微图案喷印制造，构建微纳有机传感器件。项目将有助提升电纺直写射流喷印精确调控水平，加速其产业化应用。

以其独特优势，电纺直写已在柔性微纳系统制造中表现出巨大发展潜力。项目引入交变电场，改变电荷分布迁移特性、减小干扰提高射流稳定性，以突破导电溶液在绝缘基底上单射流稳定喷射和精确定位沉积两个关键问题；并围绕交变电场诱导溶液流变与射流喷印调控机制等一类基础科学问题展开研究。构建了电纺直写数值仿真模型，分析了交变电场诱导作用下导电溶液的电荷分布规律和迁移行为，讨论了导电溶液流变特性和边界层演变机制；考察了电场参数、溶液特性等因素对单射流喷射的影响规律；明确了仿真射流内部的电荷分布及射流中心速度随喷射时间和喷射距离的变化规律，分析了射流内部电荷变化对射流与收集基底之间相互作用机理；研究了导电单射流启动、喷射、停止的临界条件和控制规律，实现了导电单射流快速启停控制；考察了交变电场诱导单射流在硅基底上的喷印沉积行为，并分析了实验参数对喷印液滴沉积频率与直径的影响规律；研究了交变电场诱导单射流在绝缘PET基底的沉积规律，交变电场可克服在柔性绝缘基底上聚合物溶液电纺直写易产生的射流分叉、难以诱导单射流稳定喷射的困难；开展了一系列实验研究，总结了交变电场参数、加工参数等对单射流沉积行为的影响规律，掌握了其精确定位沉积控制策略，在绝缘基底上实现了有序、均匀的沉积液膜的直写制造；针对交流诱导电纺射流喷印需求，设计了正弦高压交流电源，通过原理分析及参数计算，设计了推挽式直流变换电路、SPWM逆变电路以及控制电路等；基于调试完成的正弦高压交流电源，分析了射流运动及沉积规律，验证了交流电纺在绝缘基底上实现喷印的可行性，并初步探究了绝缘基底上微纳结构沉积规律；实现了导电功能性微纳结构在绝缘基底的定位沉积和微图案喷印制造，构建了微纳有机传感器件。项目将有助于提升电纺直写射流喷印精确调控水平，加速其产业化应用。