Study On Numerical Simulation And Experiment Of Microinjection UV-curing Mold Filling

With the development of contemporary technology,various instruments and equipment are developing towards refinement and high efficiency.To meet the requirements of equipment refinement,the internal components of the equipment are also required to be refined and integrated.The emergence of microfluidic chips is also due to the trend of high efficiency and miniaturization in daily inspection and packaging.Microfluidic chips have applications in many aspects of life.For example,it is used for disease detection in medical testing.A small number of patterns are combined with detection reagents to obtain results.The detection process requires fewer patterns and multiple items can be tested at the same time.The microfluidic chip also leads the development of detection,synthesis and other aspects to high efficiency,integration and economy.The light-curing microfluidic chip is a branch of the microfluidic chip.Unlike ordinary resins,the lightcuring material is fluid at room temperature again.It does not need to be melted and plasticized during the injection molding process.It is directly injected into the cavity and uses ultraviolet light The photocurable material undergoes a chemical reaction to undergo crosslinking,generates macromolecular chains,and solidifies and forms.Due to the abovementioned characteristics,the light-curing microfluidic chip has the advantages of simple molding operation,energy saving,etc.compared with ordinary resin in the production process.However,in the actual application process of the light-curing microfluidic chip,the mechanical properties are inferior to the microfluidic chip made of ordinary resin.The light-cured microfluidic chip has poor impact strength and plasticity,and can be used in place of a resin microfluidic chip when the mechanical properties of the microfluidic chip are not required to be high.In this paper,through the design of UV light-curing micro-injection molding equipment,light-curing microfluidic chip injection molding,the influence of process parameters on the molding defect quality and microstructure of the microfluidic chip are studied,and the better molding parameters are determined.Compared with the method of numerical simulation,the filling process of microfluidic chip is analyzed.The microfluidic chip packaging bonding process and the influence of process parameters on bonding strength were studied.This article conducted the following research work:1.Design and manufacture UV light curing injection molding equipment.Make the injection process mold meet the requirements of making the product molded and capable of complete demoulding.The ultraviolet lamp cap ensures that the irradiation can completely cover the mold cavity,and at the same time,the irradiation intensity and the irradiation time can be adjusted.During the irradiation process,the irradiation light source can move freely in both the X-axis and Z-axis directions.2.Using the fluid analysis software fluent to perform finite element analysis to explore the causes of defects in the forming process of the lightcured microfluidic chip.The effects of mold filling pressure,material viscosity,and aspect ratio of the microstructure on the filling rate of the microstructure of the photocurable microfluidic chip were analyzed.The filling rate is better when the mold filling pressure is about 0.6MPa;as the viscosity of the material increases,the filling rate has a downward trend;the larger the aspect ratio of the microstructure,the more difficult it is to achieve filling,causing defects in the final product.3.The influence of process parameters on the molding quality of photocuring microfluidic chip was studied.By analyzing chip defects of microfluidic chips made of photo-curable materials with different formulations,summarizing the cracks and their causes,the formulations were optimized.The influence of light intensity,holding pressure and other process parameters on chip molding quality is analyzed.Summary for the photocurable microfluidic chip,the process parameters are injection pressure 0.6 MPa,holding pressure 0.2 MPa,scanning speed 10 mm/s,and UV light intensity 80%quality.4.Studied the relationship between the process parameters and bonding strength of the microfluidic chip bonding process For microfluidic chips that are cured by ultraviolet light injection molding,the direct pressure bonding has low bonding strength;the adhesive bonding method will generate a large number of bubbles,which is easy to contaminate and block the microchannel.In this paper,the direct pressure illumination method can effectively solve the microfluidic chip bonding problem,no bubbles will be generated,and the bonding strength meets the application requirements.