| Compared with the traditional solvent-based system,the water-based epoxy resin system avoids the generation of harmful volatile substances(VOC,volatile organic compound),in line with the society's goal of pursuing a green and healthy environment,the green water-based epoxy resin and its application have attracted much attention in recent years..In this study,the excellent comprehensive performance of the waterborne epoxy resin system was achieved through chemically modified epoxy resin and curing agent..This article starts with molecular design,uses conventional aliphatic polyamine as raw material,monoepoxy compound as end-capping agent,epoxy resin as chain extender,and synthesizes an aqueous ring with self-emulsifying effect Oxygen curing agent.The synthetic waterborne epoxy resin curing agent was characterized by FT-IR.The test results showed that all the epoxy groups participated in the reaction,and the characteristic peaks of the groups disappeared.A four-factor three-level orthogonal experiment was designed by orthogonal experiment,and the influence of epoxy resin type,polyamine type,reactant ratio and salt formation rate on the result was investigated.Finally,the result was verified and the preparation of waterborne epoxy was obtained.The most suitable conditions for the emulsion system: E-44 is selected for epoxy resin,and diethylene triamine is selected for polyamine,and the molar ratio of the two is 1:3,and the salt formation rate is 60%.On the basis of the previous research,a waterborne epoxy emulsifying curing agent containing short fluorocarbon chain structure was synthesized,and emulsified with fluorine-modified epoxy resin to prepare an environmentally friendly,hydrophobic short fluorine-containing curing agent.Waterborne epoxy resin with carbon chain structure.contact angle testing,FT-IR,AFM,TGA,DMA and other analytical methods were used to characterize and study the structure of the resin,surface properties,thermal properties and mechanical properties of the cured film results show that the heat resistance and hydrophobicity of the fluorine-containing epoxy were improved to some extent compared with the fluorine-free system,and a small amount of fluorine 2.4% can reach the hydrophobic effect.The glass transition temperature increased from 89? to 101?.The surface roughness is also improved,so that the water contact angle is further increased to an optimum 98°.The cured film obtained the best thermal stability,and the maximum thermal decomposition temperature was 373.1 °C.According to the non-isothermal differential scanning calorimetry curve,the synthesized fluorine-containing water-based epoxy resin was studied by the method of chemical thermal reaction kinetics.Through the Malek method,the kinetic parameters of the curing reaction were solved.It was also found that the Crane equation could not describe the curing behavior of the epoxy resin system well.So the linear fitting method was used to obtain the reaction order,and finally combined with the n-level model and the self For the catalytic model,a more accurate model is obtained by using a piecewise fitting method. |
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