Data from research to develop chitosan-based electroconductive inks for 3D printing for EMI shielding and strain sensing applications

In this work, we developed an electroconductive ink for direct-ink-writing 3D printing that can be easily prepared without chemical reaction and exhibits excellent printability and material properties. This ink is based on chitosan as a binder, carbon fibers (CF) as a low-cost electroactive filler, and silk fibroin (SF) as a structural stabilizer. The 3D printability and flow behavior of the ink were investigated with different formulations. FTIR and TGA results showed interaction between chitosan chains and the amide groups of SF, while SEM revealed an interconnected network of CF in the composite. Using freeform 3D printing, the composite ink can form a designated pattern of electroconductive strips embedded in an elastomer, realizing an effective strain sensor for e.g. monitoring finger bending. The high printability of the ink can also be demonstrated by the printing of complex geometries without chemical or photoinitiated reactions. The composite materials are lightweight (density 0.59–0.29 g/cm3), electroconductive (2.84–2.64 s/cm), and inexpensive (20 USD/kg), with tensile strengths in the range 18.77–20.27 MPa. The 3D-printed composite had an EMI shielding effectiveness of 30–31 dB. Thus, the biopolymer-based ink developed here shows great potential for EMI shielding and other electronic applications. The data from this research include: Density of materials developed in the project; EMI shielding effectiveness; FTIR spectra; Tensile mechanical properties; Particle size; Resistivity; Rheological results; Sample preparation details; SEM images; Strain sensor data; TGA results

本研究开发了一种可用于直写式3D打印（direct-ink-writing 3D printing）的导电墨水，该墨水无需化学反应即可便捷制备，同时具备优异的打印适性与材料性能。该墨水以壳聚糖（chitosan）作为粘结剂、碳纤维（carbon fibers, CF）作为低成本电活性填料，辅以丝素蛋白（silk fibroin, SF）作为结构稳定剂。通过调整配方，研究了该墨水的3D打印适性与流动行为。傅里叶变换红外光谱（Fourier Transform Infrared Spectroscopy, FTIR）与热重分析（Thermogravimetric Analysis, TGA）结果显示，壳聚糖分子链与丝素蛋白的酰胺基团之间存在相互作用；扫描电子显微镜（Scanning Electron Microscopy, SEM）则观察到复合材料内部形成了碳纤维互联网络。借助自由式3D打印技术，该复合墨水可在弹性体中嵌入式制备指定图案的导电条带，从而实现高效应变传感器，例如用于监测手指弯曲动作。该墨水优异的打印适性还可通过无需化学反应或光引发反应即可打印复杂几何结构得到验证。该复合材料密度为0.29~0.59 g/cm³，兼具导电性（电导率2.64~2.84 S/cm）、成本低廉（20美元/千克），拉伸强度介于18.77~20.27 MPa之间。3D打印制备的复合材料电磁屏蔽效能可达30~31 dB。综上，本研究开发的基于生物聚合物的墨水在电磁屏蔽及其他电子应用领域展现出巨大潜力。本研究涵盖的实验数据包括：项目开发材料的密度、电磁屏蔽效能、傅里叶变换红外光谱、拉伸力学性能、粒径分布、电阻率、流变学测试结果、样品制备细节、扫描电子显微镜图像、应变传感器数据以及热重分析结果。