Study On Compatibilization Of Carbon Dots On Carboxylic Nitrile Rubber/Silicone Rubber

Polymer blending modification is an effective way to improve material properties,develop new materials and balance material prices.It opens up a broad way for the development and utilization of polymer materials.Carboxyl nitrile rubber(XNBR)is a synthetic rubber obtained by introducing a small amount of methacrylic acid monomer or acrylic acid into the molecular chain of NBR.In addition to oil resistance,heat resistance,and aging resistance,it also has high strength and abrasion resistance.Good and easy bonding properties.Methyl vinyl silicone rubber is made by copolymerization of dimethyl siloxane and a small amount of vinyl siloxane.It has excellent high and low temperature resistance,electrical insulation,and aging resistance,but its mechanical strength is poor.Blending nitrile rubber with silicone rubber can not only improve the low temperature performance of nitrile rubber,but also maintain its oil resistance.However,blending modification requires good compatibility between the two materials,which requires us to improve the compatibility between polymers and to study new methods to improve the compatibility of polymers.In 2004,carbon quantum dots were accidentally discovered as a by-product and became a research hotspot in carbon nanomaterials.Their easy functionalization characteristics make them have broad prospects for use as compatibilizers.This paper focuses on the preparation and characterization of carbon quantum dots and the compatibilization of carbon quantum dots on the carboxyl nitrile rubber/silicone rubber system.The main research contents are as follows:(1)Using different silane coupling agents and citric acid as raw materials,a one-step hydrothermal method is used to prepare silanyl carbon quantum with citric acid as the carbon core and coated with silane molecular chain and three different functional groups of epoxy,amino and mercapto groups.It is found that the three kinds of carbon quantum dots have a relatively regular spherical shape,uniform size distribution,and good fluorescence performance.(2)The effect of adding carbon dots as a compatibilizer on the blending system of carboxylated nitrile rubber/methyl vinyl silicone rubber(XNBR/MVQ)was studied.The compatibility between the carbon quantum dots and the raw material silane coupling agent,the carbon quantum dots with different functional groups,and the different addition amounts were discussed.It was found that the addition of carbon quantum dots can maintain oil resistance while combining the two groups The glass transition temperature of the components is shortened,and the size of the dispersed phase is significantly reduced,the tensile strength is increased,and the compatibility of the incompatible polymer system is improved.