Preparation And Properties Of Self-emulsifying Epoxy Emulsifier With Corrosion Inhibition

Usually,the traditional epoxy resin is viscous liquid or solid,soluble in organic solvents,but insoluble in water.So,plenty of organic solvent is required in using epoxy resin to produce coating products.Therefore,this will inevitably cause a lot of environmental problems,and it also do harms to the construction and practitioners’ health.At the same time,with the global energy and resource crisis is increasing,the traditional high-pollution resin coating products have been unable to meet the requirements of modern industrial development.So people put forward the concept of waterborne epoxy resin.Waterborne epoxy resin use water as dispersant,with low VOC(volatile organic matter)characteristics.It’s a kind of environmental friendly material.Thus,more and more researchers have paid attention to this new kind of epoxy resin.In order to study the development of self-emulsifying epoxy resin with the aim of industrial demand,a self-emulsifying epoxy resin(emulsifier)with corrosion inhibition was developed by chemical modification method in this paper.And the finial research results will be used in the coatings industry.The research is divided into two parts.First,epoxy resin(E-44)was chemically modified with glycine polyethylene glycol(PEG),to prepare stable epoxy emulsions.The effect of the ratio of glycine to polyethylene glycol(200,400,1000,1500),the reaction ratio of glycine to epoxy group,reaction temperature and reaction time on the modification reaction of epoxy resin was studied.And then the optimal modification conditions and methods of the experiment were determined in this paper.Research shows that: with the increase of glycine and epoxy mole ratios,and the increase of the molecular weight of polyethylene glycol(200-1500),the particle size of the aqueous epoxy emulsion gradually becomes smaller and the stability of the emulsion system is improved,Above all,the glycine-polyethylene glycol 1500 modified epoxy resin E44 obtained by the performance of the emulsion is the best.When n(epoxy): n(glycine): n(polyethylene glycol 1500)=1:1:1.5,the synthesis conditions of amino terminated polyoxyethylene ether: pH=9,synthesis temperature is 120℃,reaction time in 2 hours;ring opening reaction conditions of modified epoxy resin is pH=9,reaction temperature is 80℃,reaction time in 6 hours.The water solubility of the modified poly(ethylene glycol)1500modified epoxy resin is the best,and it has good performance in emulsification,dispersion,film quality and stability.In addition,it is recommended to use glycine-polyethylene glycol1000 as a modifier in view of the corrosion resistance of waterborne epoxy resin,and the modified epoxy resin is excellent in water dispersibility and corrosion resistance.Second,in view of the application and development of waterborne epoxy resin in heavy anti-corrosive coatings,the corrosion resistance of epoxy resin emulsion and waterborne epoxy resin coating were studied and characterized in this paper.The aqueous epoxy resin emulsion was prepared by inverse reversing method using glycine-polyethylene glycol 1500 modified epoxy resin reactant as self-made emulsifier,and the varnish coating and the prepared coating were subjected by electrochemical corrosion and other tests.The results showed: when the ratio of self-made emulsifier to epoxy resin E44 is 0.8: 1,the epoxy resin emulsion prepared by reverse rotation method has good emulsion stability and practicability.Also,the curing temperature is 60℃,The curing agent can be cured for 3-4h to obtain the ideal water-based epoxy resin curing coating,the coating in the coating quality and corrosion resistance have a better performance.At the same time,in order to study and improve the corrosion resistance of waterborne epoxy coatings,before the preparation of waterborne epoxy resin coatings,respectively with silane coupling agent and filler on corrosion inhibitor(sodium molybdate,Zinc Oxide)after pretreatment can improve the corrosion resistance of coatings.In this experiment,when KH550:Zinc Oxide=3:1;KH560:sodium molybdate=2:0.6;Modified inorganic materials in the paint anti-corrosion performance is better than the performance of unmodified inorganic materials.The mechanism of application of the silane coupling agent in aqueous(epoxy)coatings is further clarified.