基于宾汉流体支撑的凝胶3D打印工艺研究

发布时间：2019-04-10 12:41

【摘要】：增材制造(3D打印),兴起于20世纪90年代,目前在汽车、建筑、医疗等领域已经得到广泛的应用。3D打印具有快速响应、操作便捷、个性化定制等优点,并受到越来越多的关注。在过去的几十年间,3D生物材料打印之路已经从快速成型用于发展和研究的医学辅助工具,走向了私人定制的医学装备。3D凝胶打印作为3D生物材料打印的一种,其原理是把生物材料按照一定的规律沉积形成3D实体。若将生物材料混合细胞,再利用3D打印技术制造成实体,后期经过进一步培养可得到具有生物活性的器官模型。因此,研究并改善凝胶打印工艺,实现精准控形对3D打印在生物领域的应用具有重要意义。本文在分析海藻酸钠凝胶的可打印性研究的基础上,优化了凝胶的打印参数和路径,提高了打印精度。本文对宾汉流体的特性进行了理论研究,并进一步提出基于明胶支撑材料的挤出成型凝胶打印工艺。探索了明胶材料作为支撑的性能与制备方法,完善了凝胶在支撑中的打印工艺参数。另外,针对不同的影响因素,本文对凝胶的力学性能研究进行了一系列对比实验探究。最后利用明胶支撑打印工艺打印实体结构、空间结构、分叉结构和Y型结构实例,探索该工艺在医学领域中的潜在应用。论文主要开展的工作如下:一、凝胶生物打印参数设置和打印工艺的探索。包括打印工艺平台设计和打印参数实验。合理设置在点、线、体凝胶结构成型中的打印参数及路径优化,使凝胶结构获得较好的尺寸精度与整体度。最后通过细胞实验验证凝胶的生物兼容性及打印过程的无害性。二、分析宾汉流体的物理特性,通过建立宾汉流体在凝胶3D打印中的物理模型,探索其与打印参数的物理关系。从理论上分析支撑材料的打印性能。三、明胶支撑中的凝胶打印工艺探索及优化。研究支撑材料的性能及配制工艺,优化凝胶打印参数,实现精准控形和复杂结构的打印。其中,运用理论分析凝胶材料在长喷头中的压力损失,解决喷头长度与气压参数的选择问题。四、利用基于明胶支撑的打印工艺打印不同类型结构,探索其在医学领域内的潜在应用。打印3D人体肝脏结构以验证此方法能打印整体性结构,打印空间线条结构以验证此方法能打印多种材料结构,打印血管分叉结构以验证此方法能控制材料在空间的精确沉积,打印Y型血管结构以验证此方法能制造结构的内部流道。
[Abstract]:3D printing has been widely used in automotive, architectural, medical and other fields at present. 3D printing has the advantages of rapid response, convenient operation, personalized customization and so on, and it has been widely used in the field of automobile, architecture, medical treatment and so on, and it has the advantages of rapid response, convenient operation and customization. And received more and more attention. Over the past few decades, 3D biomaterial printing has moved from a rapid prototyping medical aid tool for development and research to private medical equipment. 3D gel printing is one of 3D biomaterials printing. Its principle is to deposit biomaterials according to certain laws to form 3D solid. If the biomaterial was mixed with cells and then made into solid by 3D printing technology, the biological organ model could be obtained by further culturing at the later stage. Therefore, the study and improvement of gel printing technology and the realization of accurate shape control are of great significance to the application of 3D printing in biology field. On the basis of analyzing the printability of sodium alginate gel, the printing parameters and paths of the gel were optimized and the printing precision was improved. In this paper, the properties of Bingham fluid are studied theoretically, and the gel printing process based on gelatin supporting material is further proposed. The properties and preparation methods of gelatin as support were explored, and the printing parameters of gel in support were improved. In addition, a series of contrastive experiments were carried out to study the mechanical properties of gel according to different influencing factors. Finally, the solid structure, spatial structure, bifurcation structure and Y-type structure of gelatin-supported printing process are used to explore the potential application of this technology in medical field. The main work carried out in this paper is as follows: first, the setting of biologic printing parameters and the exploration of printing technology. Including printing process platform design and printing parameters experiment. The printing parameters and the path optimization of the gel structure are reasonably set in the point, line and volume gel forming, so that the gel structure can obtain a better dimensional accuracy and integrity. Finally, the biocompatibility of the gel and the innocuity of the printing process were verified by cell experiment. Secondly, the physical properties of Bingham fluid are analyzed, and the physical model of Bingham fluid in gel 3D printing is established, and the physical relationship between Bingham fluid and printing parameters is explored. The printing properties of supporting materials are analyzed theoretically. Thirdly, the research and optimization of gel printing technology in gelatin support. The properties and preparation technology of supporting materials were studied, and the printing parameters of gel were optimized to achieve accurate shape control and complex structure printing. The pressure loss of gel material in long nozzle is analyzed theoretically, and the selection of nozzle length and pressure parameter is solved. Fourth, using gelatin-supported printing process to print different types of structures, to explore its potential applications in the field of medicine. Print 3D human liver structure to verify that this method can print holistic structure, print spatial line structure to verify that this method can print a variety of material structures, print vascular bifurcation structure to verify that this method can control the accurate deposition of materials in space. Print the Y-type vascular structure to verify that this method can make the internal passage of the structure.
【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：R318.08;TP391.73

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