Study On Preparation And Performance Of Primer For Silicone Rubber

Silicone rubber is a typical non-polar material,which has good physical and mechanical properties,good high and low temperature resistance,excellent processing performance,and good electrical insulation;ozone resistance,radiation resistance,and corrosion resistance are excellent,low activity,non-flammable,non-toxic,high safety,etc.,so it is widely used in automotive,electronics,construction,computer,medical and other industries.However,silicone rubber does not contain active groups,the surface energy is low,there is a weak boundary layer,and the interface wettability is poor.Therefore,the adhesion performance of the surface of the silicone rubber is poor,which makes it difficult to effectively bond with other materials,becoming a problem in bonding technology.In response to this problem,this article carried out the following experimental research:In this paper,two primers for improving the adhesive properties of silicone rubber were successfully prepared using acrylate and silane as raw materials.After the silicone rubber is treated with the homemade primer,a new surface treatment layer will be formed on the surface,and the surface morphology and static contact angle of the silicone rubber before and after the primer treatment are characterized and analyzed.The influence of each component of the primer on the performance of the primer was studied,and the influence of the preparation process and construction process conditions of the primer on the adhesion properties of silicone rubber and pressure-sensitive adhesive was analyzed.The experimental results show that the adhesion of the new surface layer formed by treating the silicone rubber with the acrylic primer to the silicone rubber can reach level 1,because the coating has polar groups such as ester groups and the polar groups of the pressure-sensitive adhesive have the similar structure,and the interaction force is strong,so that the shear bonding strength of the silicone rubber and the pressure-sensitive adhesive can reach up to 1.79 MPa,Compared with unmodified silicone rubber,it is increased by 280.9%.The acrylic primer can maintain a stable homogeneous system after being sealed for 3 months,and has good storage stability.The silicone primer made from trifunctional aminosilane and methyl orthosilicate silane monomer has good performance and storage stability can exceed 30 days.The silicone primerhas good compatibility with silicone rubber,the adhesion between the cured coating film formed by brushing the surface of the silicone rubber with the primer and the silicone rubber can reach level 1,the polar groups such as amino groups in the coating film can interact with the polar groups of the pressure-sensitive adhesive,so that the shear bonding strength of the silicone rubber and the pressure-sensitive adhesive can reach up to 1.98 MPa,Compared with unmodified silicone rubber,it is increased by 321.3%.