Research On Piezoelectric Micro - Spray Forming System For PLGA Three - Dimensional Printing

Piezoelectric droplet spray 3D printing is an advanced rapid prototyping technology. It has so many advantages that has a good application prospect in the biological manufacturing and micro manufacturing, especially when the structure of the machining part is simple and have a high precision. The piezoelectric droplet spray forming system is studied in this paper. The main research works are summarized as follows.Firstly, based on the principles of piezoelectric droplet spray, the nozzle control system of piezoelectric droplet spray forming system is designed. The system includes piezoelectric nozzle drive control module, the nozzle temperature control module, the pressure control module, liquid storage mechanism. The construction and debugging of the nozzle control system is also finished.Secondly, the motion control system of piezoelectric droplet spray forming system is designed, including three-axis motion control module, the limit switch control module and communication transmission module. This paper expounds the design idea and implementation scheme in detail. The motion control system of piezoelectric droplet spray forming system is built and debugged.Subsequently, the piezoelectric droplet spaying process is simulated with the fluent software. The relationship between the system parameters (nozzle diameter and solution viscosity) and the droplet diameters are discussed to provide theoretical basis for PTX/PLGA microspheres preparation.Finally, the piezoelectric droplet spray forming system designed in this paper is used to prepare PTX/PLGA microspheres. Meanwhile, the experiment shows that this system can produce homogeneous drug-loaded microspheres. The relationship between the system parameters (the driving voltage, nozzle diameter, driving frequency and the solution viscosity) and drug-loaded microspheres size is discussed to verify the result of numerical simulation. On the basis of the drug-loaded microspheres preparation, arbitrary three-dimensional structure forming method is discussed.The piezoelectric droplet spray forming system in this paper has many advantages, such as high consistency and good controllability of the sprayed droplet as well as high stability, high injection frequency and wide selection of the liquid viscosity. It has important theoretical and practical values.