Preparation Of Organic - Inorganic Hybrid Modified Epoxy Resin Coatings And Its Performance In Produced Water

Oilfield produced water is a byproduct during the exploiting process of oil. Produced water has complex composition and the production is huge, the oilfield produced water environment usually with high temperature, high salinity, low pH and other characteristics, so the corrosion and protection of oilfield produced water environment has become a research that oilfield focus on. Epoxy resin coating has poor toughness and high temperature performance, but the small shielding effect of Cl-affects its applications in oilfield produced water. In view of this situation, a kind of organic-inorganic hybrid coating of epoxy resin modified silicone material was developed this paper, which has the advantages of both organic and inorganic materials, provides a new anti-corrosive coating for oilfield produced water environment, and through the research of physical properties, heat resistance, chemical resistance properties and anti-corrosion properties in oilfield produced water, get the the anti-corrosion mechanism of the modified coating in the oilfield produced water.The sol-gel is used to prepare epoxy resin modifier:organic-inorganic hybrid sol. By single factor and orthogonal experiments to determine the organic-inorganic hybrid sol optimal synthesis conditions and the best ratio:KH-560(20mL), TEOS(lOmL), isopropanol (20mL), deionized water (2.1mL), pH value of10, deionized water and isopropyl alcohol mixed droplet acceleration rate0.5mL/min, room temperature hydrolysis2h,70℃polycondensation6h. Under these conditions, the gel time of synthetic organic-inorganic hybrid sol at room temperature reaches50d, and its solids content can reach37%.Prepared without adding modifiers epoxy varnish and nine kinds of different organic-inorganic hybrid sol/epoxy varnish, determined by single factor experiment curing agent for epoxy resin varnish mixed solvent usage, research the impact modifiers on curing time and curing degree. The physical properties of the varnish, chemical resistance, water resistance, heat resistance and the anti-corrosion properties in oilfield water were tested, the results showed that:organic-inorganic hybrid sol and epoxy mass ratio of5:4reachs the best properties, you get hybrid modified epoxy resin varnish adhesion to a hardness of0.993, impact strength of40kg·cm; twice decomposition temperature reached200℃and400℃; chemical resistance and thermal performance has improved greatly compared with unmodified sample; the coating resistance of the modified varnish reached107Q/cm and104Ω/cm when immersed in simulated oilfield produced water at40℃for1d and7d, which is two orders of magnitude than that of pure epoxy resin coating.Prepared organic-inorganic hybrid modified epoxy paint. The physical properties and chemical resistance of the paint were tested. Using EIS test and autoclave test to study the anti-corrsion properties in simulated oilfield water. The results showed that:organic-inorganic hybrid modified epoxy paint impact strength reaches45cm·kg which is better than varnish; chemical resistance is also better than the varnish, the pait unchanged after immersed in a solution of10%HCl and10%NaOH solution for7d; EIS test shows that as immersion time increases, the coating resistance is reduced, the coating resistance decreases slowest at50℃and it shows the best anti-corrosion properties; When immersion time reached14d, the paint showed warburg impedence, the coating resistance reached105-106Ω/cm2which is better than the varnish immersed7d at the same temperature; The paint coating immersed in simulation oilfield produced water in autoclave for48h with the condition of100℃,2MPa CO2shows good corrosion resistance performance by the SEM and EDS methods.