Effect Of Nano Carbon-silver Composite Antibacterial Agent On The Antibacterial And Mechanical Properties Of Silicone Rubber

Objective:The antibacterial silicone rubber based on Ag@C antibacterial agent was constructed,and the influence of antibacterial agent on its antimicrobial and mechanical properties was studied,so as to provide theoretical basis and technical support for the preparation of biomedical silicone rubber with high efficiency and lasting antibacterial effect.Methods:1.The preparation and characterization of Ag@C antibacterial agent.Nano carbon coated silver(Ag@C)antibacterial agent was prepared by hydrothermal method using silver nitrate and glucose as raw materials.Its microcosmic morphology,molecular structure and thermal oxidation stability were characterized by scanning electron microscopy(SEM),transmission electron microscopy(TEM),Fourier transform infrared spectroscopy(FT-IR)and thermogravimetric analysis(TG).The antibacterial properties of Ag@C were evaluated by inhibition ring and the method of plate culture count.2.The preparation and characterization of antibacterial silicone rubber.Using silicone rubber(SR)and Ag@C as raw materials,the antibacterial SR was prepared by mixing and vulcanizing method.The dispersion of Ag@C in silicone rubber was analyzed by SEM.The thermal oxidation stability and mechanical properties of Ag@C/SR composite were analyzed by TG and electronic universal testing machine.Finally,the antibacterial properties of Ag@C/SR composites were tested by using inhibition ring and the method of plate culture count.Results:1.Ag@C antimicrobial agent is spherical with uniform size distribution,the average particle size is about 316 nm.The surface of Ag@C is rich in reducing functional groups,which indicates that nano carbon and nano-silver(Ag NPs)are effectively combined,and the surface is rich in oxygen-containing functional groups.Ag@C has excellent thermal stability.The initial decomposition temperature is 300℃,which solves the problem of easy oxidation of Ag NPs.The content of Ag NPs is about 1.1%.In addition,Ag@C antibacterial agent had good antibacterial effect on Escherichia coli and Staphylococcus aureus.The diameter of inhibition ring was 9.6mm and 12.5mm,respectively,and the antibacterial rate reached 96.4% and 97.8%,respectively.2.Based on the analysis of the structure and properties of Ag@C/SR,it can be seen that Ag@C particles have good dispersion in the SR matrix,most of which are evenly distributed,and Ag@C/SR has good thermal stability,and the initial decomposition temperature is 300℃.It has good antibacterial effect on Escherichia coli and Staphylococcus aureus.In addition,when the amount of Ag@C is 0.5‰～0.75‰,the tensile strength and fracture energy of SR are improved,but the elongation at break of SR is decreased.Conclusion:In this study,Ag@C composite antibacterial agent was successfully prepared by hydrothermal method,which not only has high antibacterial efficiency,but also solves the problem of easy oxidation of Ag NPs,and has good thermal stability.Moreover,SR was modified with Ag@C composite antibacterial agent,which not only gave SR excellent antibacterial properties,but also improved the tensile strength and fracture energy of SR.Ag@C/SR composite material with excellent antibacterial and mechanical properties was formed,which provided a theoretical basis for the preparation of a new antibacterial silicone rubber with durable antibacterial properties and low price.