Formulation: development of two component waterborne epoxy anticorrosive coating

Core tip: 0 Introduction The corrosion of metal is mainly caused by chemical or electrochemical reactions between metal and its contact medium, which damage the metal structure and cause the equipment to be scrapped Metal corrosion causes a lot of waste of resources and energy in the national economy The economic loss caused by corrosion in the world is about 1 trillion US dollars every year, which is the total loss caused by fire, wind and earthquake As the most effective, economical and widely used anti-corrosion method, coating anti-corrosion coating has been widely concerned and valued at home and abroad With the development of China's construction, transportation, petrochemical, power and other industries, Paint knowledge how about Akzo Nobel Powder Coating Recommended introduction: powder coating is a kind of coating with different form from general coating, which is in powder form It is a new type of coating, because of its own advantages and more and more known by people Let's introduce Akzo Nobel Powder coating Akzo Nobel Powder coating is a cost-effective coating solution, which can be applied to different kinds of products After the treatment of static electricity and fire baking, a tough and durable coating surface will be formed, with the least impact on the environment Since the introduction of this technology, powder coating has been able to continue to maintain the The corrosion of metals is mainly caused by the chemical or electrochemical reactions between metals and the media they contact, which damage the metal structure and cause the equipment to be scrapped Metal corrosion causes a lot of waste of resources and energy in the national economy The economic loss caused by corrosion in the world is about 1 trillion US dollars every year, which is the total loss caused by fire, wind and earthquake As the most effective, economical and widely used anti-corrosion method, coating anti-corrosion coating has been widely concerned and valued at home and abroad With the development of construction, transportation, petrochemical, electric power and other industries in China, the market scale of anticorrosive coatings has been ranked second only to that of architectural coatings According to statistics, the total production of anticorrosive coatings in China reached 600000 tons in 2004, and it is expected to break the 1 million tons mark in 2020 The epoxy coating is the most representative and the most widely used high-performance anticorrosive coating The traditional epoxy resin is difficult to dissolve in water, and can only dissolve in aromatic, ketone, alcohol and other organic solvents It must be diluted with organic solvent as the dispersion medium, and can be used only when it is compounded into a certain concentration and viscosity of resin coating Using organic solvent as dispersion medium to dilute epoxy resin is not only costly, but also harmful to human body and environment For this reason, many countries have issued strict regulations to limit VOC emissions, and the waterborne technology of epoxy resin has become a research hotspot in various countries Since 1970s, environmental friendly waterborne epoxy system has been studied abroad In China, waterborne epoxy system and waterborne epoxy coating have been researched and developed since the early 1990s In this paper, waterborne epoxy resin emulsion and polyether waterborne epoxy resin curing agent were designed and developed, and two component waterborne epoxy anticorrosive coatings were prepared Their physical and chemical properties were excellent 1 experimental part 1.1 raw materials Polyethylene glycol 1000, polyethylene glycol 1500 and polyethylene glycol 4000: Tianjin kemio chemical reagent development center; bisphenol A epoxy resin E20 and E51: Jiangsu Sanmu Group Co., Ltd.; potassium persulfate: Tianjin Tianda chemical experiment plant; aliphatic monocyclic oxide: Wuxi Jiuyan anticorrosive material Co., Ltd.; diethylenetriamine: Weifang Sinochem Trade Co., Ltd.; acetic acid: Jinan Sanen Chemical Co., Ltd.; deionized water: self-made; wetting dispersant, defoamer, base material wetting agent, iron oxide black: Bayer company of Germany; multifunctional assistant: Dow company of the United States; aluminum tripolyphosphate: Shijiazhuang Xinsheng Chemical Co., Ltd.; anti flash rust agent: Yanzhou Haoran Chemical Co., Ltd.; thickener: Beijing Dongfang Aohan Co., Ltd 1.2 instrument to6001 electronic balance: Tianjin Balance Instrument Co., Ltd.; jj-1 power increasing electric mixer, QSM-II sand grinder, QHQ film pencil hardness scratch hardness tester, QTX film elasticity tester, qfz-ii film adhesion tester: Tianjin material testing machine factory; ywx / q-150 salt spray test box: Wuxi Sunan Test Equipment Co., Ltd 1.3 synthesis of reactive epoxy resin emulsifier The epoxy resin and polyethylene glycol were added into a 250ml three bottle with a certain molar ratio (the molar ratio of epoxy group and hydroxyl group is 1:1) equipped with a stirrer and a thermometer, and heated After the epoxy resin and polyethylene glycol were melted and mixed evenly, potassium persulfate aqueous solution was added in drops at 80 ℃, 100 ℃, 120 ℃ and 150 ℃, respectively, and then added in drops within 2H Control the reaction at this temperature and keep it warm for 6h 1.4 waterborne epoxy emulsion was prepared by adding E-51 epoxy resin to the high shear homogeneous emulsification reactor at a mass ratio of 4: 1 with the above reaction epoxy emulsifier, stirring at 50 OC, mixing evenly and dropping deionized water until the electrical conductivity suddenly increased At this time, the continuous phase of the system changed from epoxy resin to water phase, and the phase inversion occurred After continuous stirring at a high speed for a period of time, a suitable amount of deionized water was added to make waterborne epoxy emulsion with a solid content of 65% 1.5 synthesis of polyether type waterborne epoxy curing agent the ratio of epoxy resin E-20 to polyethylene glycol 1500 is 2:1, which is added into the reactor, stirred, heated to 60 ℃, after the reactant is melted, the catalyst potassium persulfate is added, after the reaction for 8 hours, diethylenetriamine is added, heated to 120 ~ 130 ℃, and the reaction is held for 2 hours to produce amine capped epoxy adduct Remove excess diethylenetriamine by vacuum distillation The curing agent of epoxy resin was prepared by adding aliphatic monocyclic oxide, heating to 140 ℃, holding for 2 h, adding acetic acid at 100 ℃, reacting for 1 h 1.6 preparation of two-component waterborne epoxy anticorrosive coating the formula of two-component waterborne epoxy anticorrosive coating is shown in Table 1 Home of coatings is specialized in coatings, diatom mud, paint coating, coating technology, fire retardant coating news and coating, diatom mud, paint coating, coating technology, fire retardant coating decoration knowledge and decoration renderings,