Preparation And Properties Of Conductive Silicone Rubber Model

Precision texture mold is a new type of mold with complex structure and micron-scale texture on the surface.It has been widely used in automotive,electronic communication and instrumentation.The texture information on the precision texture mold is derived from the original cladding model or the laser engraving model,and is transmitted by the silicone rubber reprint model.After surface metallization,the silicone rubber reprint model is obtained a metal mold with the same fine structure.Since the mold manufacturing process involves various mold reversal and conductive treatment,it is easy to cause problems such as texture distortion and dimensional deformation.Therefore,this paper adopts the solution dilution method and the co-curing method,and uses conductive carbon black and graphene oxide as conductive fillers to prepare the additive conductive silicone rubber material and reprint model,which with excellent emulation and dimensional stability.The curing ability,conductive mechanism,surface metallization performance and texture simulation degree of the model were studied.The main research contents are as follows:The basic silicone rubber and conductive silicone rubber with conductive carbon black as filler were prepared by co-curing.Combined with demolding effect,texture reprinting effect and cross-linking density,the optimum cross-linking amount of basic silicone rubber and conductive silicone rubber was 12 and 20 parts respectively.The silicone rubber does not cure due to the addition of conductive carbon black.It is because the water adsorbed by the conductive carbon black and the hydroxyl group on the surface react with the silicon hydrogen bond in the hydrogen-containing silicone oil,which hinders the hydrosilylation reaction between the vinyl silicone oil and the hydrogen-containing silicone oil.The degree of crosslinking of the conductive silicone rubber can be increased by increasing the amount of the crosslinking agent added.The conductive silicone rubber was prepared by the solution dilution method.The method can improve the dispersion state of the conductive carbon black in the silicone rubber,thereby effectively reducing the resistance value of the substrate.When the amount of the conductive carbon black added is 8 parts,the resistance value is decreased by two orders of magnitude,but the processing viscosity of the silicone rubber after the solvent is volatilized increases,which makes it difficult to manufacture the reprinting mold.Silicone rubber reprint model with conductive carbon black as filler was prepared by co-curing method.The conductive properties and thermal stability of the silicone rubber reprint model were studied.The obtained conductive silicone rubber model can withstand 500 bending cycles and the resistance value remains stable.The resistance value is 15.8 ?,which is much lower than the resistance value of the commercial conductive silicone rubber.The addition of conductive carbon black increases the thermal stability of the conductive silicone rubber.The three-dimensional imaging of confocal microscopy was used to study and calculate the pattern replication effect of the silicone rubber reprint model.The two-dimensional image proves that the conductive silicone rubber model can be used as a reprinting model;using the replication ratio at the cross-sectional line and the loss ratio R of the pattern depth of the microscope extraction surface,the loss of the texture is characterized by multiple angles.The reprinting effect of the model increases with increasing the amount of conductive carbon black.The surface metallization test of silicone rubber reprint model was carried out by electrochemical deposition method,and the relationship between surface resistance of silicone rubber and metallization performance was characterized.When the resistance value of the silicone rubber reprint model is less than 91.3 ?,the silicone rubber can achieve the electrodeposition effect of the professional Hull channel copper sheet.In the case of the same current density,the smaller the resistance value of the cathode,the faster the electrodeposition rate.In order to investigate whether the addition of graphene oxide can significantly improve the electrical conductivity of conductive silicone rubber,conductive carbon black/graphene oxide conductive silicone rubber was prepared.The experimental results show that when the addition amount of graphene oxide is 10 parts,the resistance value of conductive carbon black/graphene oxide conductive silicone rubber is 94.4 ?.However,the conductive silicone rubber with only 12 parts of conductive carbon black added has a resistance value of 91.3 ?.Graphene oxide is not suitable to be used as conductive filler of conductive silicone rubber due to its high cost,general conductivity and thermal stability.