The Research On Injection Molding Of Connector With Micro/Mini Orthogonal Hole

Connector with orthogonal micro/mini hole is consisted of orthogonal micro/mini hole and cantilevered tube.It has been widely used in biological detection,chemical analysis and optics as it can fold a straight mini/micro-channel to an orthogonal one.Due to its high efficiency and high precision,injection molding became one of the most processing methods of connectors.When the size of cantilevered tube is small enough,the phenomenon ‘short shot' may be more likely to occur.These above problems may affect the performance of the plastic parts.In order to solve the above problems and problems,the connector with micro/mini orthogonal hole was studied in this paper.On the basis of simulation and optimization,the forming method of connector with mini/micro orthogonal hole is studied.The connector with micro/mini orthogonal hole was used to make micro fluidic device with Au-three-electrode patterned.Then electrochemical detection technology was applied to detect the concentration of glucose.It mainly included the following aspects:Based on continuity equation,motion equation,energy equation,viscosity model and state equation,the model of the melt filling was established to describe the flow behavior of the melt during filling process.Moldflow software was used to optimize the gate position,gate shape and injection parameter.The best gate position should be located at the edge position on the center of the plastic part.The fan gate was used.The melt temperature made a positive effect on the filling quality of the cantilevered tube.When the mold temperature was 75 ? and the melt temperature was 225 ?,the cavity was fulfilled.Based on the connector with orthogonal micro/mini hole and cantilevered tube,it was proposed to solve the forming of orthogonal hole that the end of the side core was circular-arc-shaped to match the straight core.Injection mould with side core-pulling mechanism was fabricated.Then injection parameters were optimized by experiment.The result was proposed that the quality of cantilevered tube can be improved by increasing melt temperature.Under the condition of melt temperature 225 ?,the mold temperature 75 ?,the injection pressure 70 MPa,the holding pressure 30 MPa and the holding time 15 s,the relative length and the relative wall thickness of the tube were 98.89% and 99.80% respectively.Using the connector with orthogonal micro/mini hole,the microfluidic device with three electrodes was fabricated by photolithography,and the method of electrochemical deposition was used to modifying the electrodes.The glucose concentration was detected by electrochemical detection technique.The results show that there is a linear relationship between the concentration of glucose solution and the current response value,and the linear correlation coefficient is 0.9496.The current response value will increase with the solution flow rate increasing.