Preparation Of Waterborne Epoxy Resin System

Epoxy resin with its excellent performance is widely used in many fields,but because of existence of a long nonpolar backbone of epoxy resin,resulting in the only soluble in some organic solvents,and most of the organic solvents are toxic and volatile,leading to harm the user's body.Waterborne epoxy resin is through modification of epoxy resin,making it an oil soluble variable is water soluble,water as solvent and waterborne epoxy resin and to the environment without pollution,and operation convenience is greatly improved.In this paper,polyethylene glycol 4000 and epoxy resin(molar ratio is 1:1)as raw material,potassium sulfate as catalyst,waterborne epoxy resin emulsifier was prepared.Waterborne epoxy resin emulsion with different emulsifier content was prepared by reverse rotation method.Diethylenetriamine,epoxy resin,benzyl ether(molar ratio is 1:2:1)as raw material,waterborne epoxy resin curing agent with different salt forming rate was prepared.Then curing agent and waterborne epoxy resin emulsion were evenly mixed at room temperature(epoxy group and amine hydrogen molar ratio is 1:1).The cured condition of waterborne epoxy resin system was 70 ?,1 h;100 ?,2 h;110 ?,1 h vias DSC.The stability of waterborne epoxy resin emulsion was tested.The emulsion with 20 wt% emulsifier and 60 wt% solid content has the best stability,it can be centrifugal in 2000 r/min for 30 min without stratification.The emulsion can be placed at room temperature for 30 days without stratification which is diluted five times.It can be seen in SEM that the emulsion particle size is about 50 nm.Thermodynamic analysis of the solidified products with different salt formation rate show that the curing product with 20% salt formation rate has the best thermodynamic properties.The shear strength is 19.45 MPa,the peeling strength is 30.2 N/cm,the initial decomposition temperature is 370.63 ?.