高强
Research on Process Parameters of High Precision Direct-Ink-Write 3D Printing of Poly(L-lactide-co-ε-caprolactone)
报告人:高强
所在单位:哈尔滨工业大学精密工程研究所
个人简介:
高强，哈尔滨工业大学精密工程研究所助理研究员。多年来一直从事精密与超精密加工装备领域的相关研究，在超精密静压轴承设计理论、多物理场耦合建模方法等方面具有充分的研究基础。主持国家自然科学基金青年项目、重庆市自然科学基金面上项目、黑龙江省博士后基金面上项目等项目共6项；作为技术骨干参研国际科技合作专项、国防科工局重大项目子课题、黑龙江省重大科技成果转化项目等4项。在国内外刊物上发表学术论文20余篇，第一作者或通讯作者SCI收录论文10余篇（中科院一区TOP期刊3篇），申请国家发明专利4项。
Abstract：
The process parameters of the high precision direct-ink-write 3D printing of Poly(L-lactide-co-ε-caprolactone)(PLCL) were studied in this report. The excellent biocompatibility and high elasticity make the PLCL an ideal material which can be applied in biocompatible scaffold. Due to the low viscosity of PLCL melt, the PLCL scaffolds is highly appropriate to be manufactured by direct-ink-write 3D printing. The special rheological behavior of the PLCL which is a kind of polymer, leads to the die swell phenomenon during the printing process. That is to say the diameters of printed threads and the nozzle are different, which leads to a gap between the designed size and the true size of printed scaffolds. Adjusting the parameters of printing process based on the experience to decrease the difference between the diameters of printed threads and the nozzle is a common method to increase the precision of printing. However, this method lacks of reliability and repeatability. The purpose of this research is to explore the influence of three important process parameters of the direct-ink-write 3D printing process of PLCL on the diameters of printed threads: extrusion force, temperature and the speed of spraying. We found the optimal process parameters of the high precision printing. The viscosity curves of PLCL with varying shear rates at different temperatures varied from 180℃ to 60℃ and the complex modulus(storage modulus and loss modulus) curves with the temperature decreased from 190℃ to 10℃ were measured through the rotation rheometer, which is shown in figure 1.iii) and figure 1.iv). As shown in figure 1.i), an experimental platform which can control the extrusion force, temperature was set up to find out the relationships between these process parameters and the diameters of threads.(figure 1.ii)) The three parameters were recorded and the diameters of the printed threads was measured. And eventually, the PLCL were printed with high precision and high stability based on the optimized combination of process parameters.
