Preparation Of Environmental Protection Type Hyperbranched Modified Epoxy Resin Anticorrosive Coating

Epoxy resin has the advantages of good thermal stability,strong adhesion,preparation craftsmanship is uncomplicated and the price is cheap.It's heavily applicated in industrial applications including coating,communications,construction,etc.However,traditional epoxy resin coatings have high volatile organic compounds(VOC)content,poor impact resistance of paint films,and Antiorrosion performance needs to be improved.These shortcomings limit the further application of epoxy resins in the field of coatings.Therefore,it is an inevitable trend for future development to modify the epoxy resin coating to prepare environmentally friendly and high-performance epoxy anticorrosive coatings.In this paper,the epoxy resin coating modified by polynaphthalene type hyperbranched polymer,effects of the structure and amount of hyperbranched polymers on the comprehensive properties of anticorrosive coatings were studied.1.a high-solid epoxy anticorrosive coating with low viscosity characteristic was prepared by Introduce polynaphthalene-type hyperbranched polymer into linear epoxy resin.The research shows that the impact resistance of the modified epoxy coating is improved,and when the addition amount of hyperbranched polymer EH816 is 7%,the coating has the best antiorrosion performance,the anticorrosive coating is resistant acid resistance(10%H2SO4)for 1200h,Salt resistance(3.5%NaCl)for 2760h,alkali resistance(5%NaOH)and deionized water for more than 3600h,salt spray resistance(5%NaCl)for 2880h.Compared with E51 coating,the crosslink density of EH816 modified coating is increased by 9.21%.2.Efects of the amount of hyperbranched polymer EH816,the type and amount of reactive epoxy diluent,the solid content of the solution and the temperature on the rheological properties of the resin system were studied by using a rheometer.Studies have shown that in 80%solids resin solution,the viscosity of the system decreases first and then increases as the dosage of EH816 increases.The viscosity is the lowest when the amount of EH816 is 7-9%.In the resin/diluent mixed system,the diluent PLR603 has better viscosity reduction effect.The medium resistance experiment shows thatthe coating has good corrosion resistance when PLR603 is added in an amount of 10%.The viscosity of the resin system gradually decreases with increasing temperature.When the temperature rises to 60?,the viscosity does not change much.3.The water-based epoxy resin was converted into water by the reverse method,and the effects of emulsifier ratio and emulsification process on the particle size and stability of the emulsion were studied.The results show that the optimal emulsifier ratio is 5%NSF-1802B+1.5%SE-10N.Taking 100g emulsion as an example,the best emulsification process is:dripping rate is 1ml/min,stirring speed is 2000r/min,emulsification temperature is 60?,the design solid content of the emulsion is 50%.The particle size of the emulsion is 300?400nm,and the emulsion can be stored stably for more than half a year at room temperature.4.Using hyperbranched modified epoxy resin EH8167 as the matrix resin,a water-based epoxy anticorrosive coating was prepared.The effects of curing agent types,color paste formulations and pigment-base ratio on the physical and mechanical properties of coatings,resistance to salt spray and barrier properties were studied.the research indicates that the curing agent Aradur3986 has the best antiorrosion performance,and the overall performance of the coating is better when the pigment base ratio is 0.5:1.Compared with the unmodified coating,anti-corrosion performance of the modified coating has been greatly improved,and the medium resistance time is:acid resistance(5%H2SO4)for 300h,salt resistance(3.5%NaCl)for 500h,alkali resistance(5%NaOH)and deionized water for 2000h,Salt spray resistance(5%NaCl)for 1200h.5.Pilot scale-up experiments were carried out on water-based epoxy emulsion,water-based iron-red paste and water-based epoxy anticorrosive paint,successfully prepared 1000kg emulsion,300kg color paste and 300kg color paint.The results show that the water-based color paint has near zero VOC,good stability,no flash rust under high humidity construction,good impact performance of the paint film and excellent resistance to medium,and can be used in the field of medium and severe corrosion.