Fabrication Of Microfluidic Chip Based On UV Curing Injection Molding

In this paper, a new method of microfluidic chip forming is proposed, which is the chemical manufacturing method of UV curing injection molding. On the one hand, the method has the characteristics of fast, environmental protection and high efficiency, on the other hand the injection molding equipment can improve the shrinkage defect of products through the basic means such as holding pressure. In this paper, we designed a UV curing injection molding equipment, and solved the problem of bubble defects, and finally made a microfluidic chip which can be used as a preliminary application. The main work is as follows:1. UV curing injection molding equipment was designed and developed based on the cross structure of microfluidic chip. The equipment is mainly divided into three parts:the mold clamping unit, the irradiation unit and the injection unit. Equipment to pneumatic components as the main control mode, could control the holding pressure, mold temperature, irradiation intensity and other parameters, and it realized the semi automation.2. Based on the self-developed UV light curing injection molding equipment, a preliminary experiment was carried out on the microfluidic chip. The product had regular bubble defects. We studied the forming process visualization, the change of curing temperature and the shrinkage stress of the product, explained the reason of the bubble, and explored the solution. Studied the effects of the parameters of pressure holding pressure, irradiation intensity, material shrinkage rate and irradiation mode on the bubble number. The results showed that increasing of the holding pressure, reducing the irradiation intensity and material shrinkage rate could improve bubble defect, and scanning irradiation could greatly improve the surface quality of products.3. On the basis of solving the bubble defects, we investigated the influence of various process parameters on the micro structure of the microfluidic chip. The experimental results showed that the most obvious parameters affecting the microstructure were the holding pressure and the material viscosity, while the influence of the radiation intensity was low. The experimental results showed that UV curing injection molding had a great advantage in microstructure forming compared with traditional injection molding.4. Studied the bonding method of the microfluidic chip of the light curing material. The results showed that the method of direct pressing assisted irradiation not only had high surface quality, but also was simple and efficient.