| In recent years,people’s concept of environmental protection is increasingly strengthened,water-based paint in the coating industry is favored and concerned.Corrosion not only harms the metal itself,but also poses a great threat to the safety of human life.Water-based metallic paint is an environmentally friendly water-based industrial paint.It has the characteristics of good performance,low environmental pollution,less human hazard,and low VOC.It not only conforms to the environmental protection concept advocated by the country,but also solves the problems caused by corrosion.In this thesis,several water-based metallic paints commonly used in the market have been prepared by means of formula optimization and raw material screening to test comprehensive performance.The main work of this paper:1.Preparation and performance of water-based acrylic metallic paint Using water-based acrylic emulsion,anionic water-based acrylic emulsion and water-based self-emulsifying modified acrylic resin as film-forming materials,water-based acrylic metal paint was prepared separately,and the comprehensive performance was tested according to HG/T 4758-2014 "Water-based Acrylic Resin Coatings",and the anion was determined Type acrylic emulsion AC.1,AC.2,AC.5,water-based acrylic emulsion AC.6,and self-emulsifying modified acrylic resin AC.7are the main film-forming products.2.Formula optimization of water-based acrylic metallic paintSelect AC.2 as the film-forming material,carry out quantitative and qualitative experiments on the experimental raw materials,and determine the optimized water-based acrylic metallic paint formula.After testing,some performances have been improved,and they are all in line with industry standards.Due to its poor corrosion resistance,it can be used as a light anti-corrosion primer for steel structures and low-cost steel structure bottom surface water-based metallic paint;the hardness of the paint film prepared with AC.1 is increased to HB,the gloss is 72.9 Gs,and it can be used as water-based Acrylic metal topcoat;the gloss of the paint film prepared with AC.5 emulsion exceeds 90.0 Gs,and the salt spray resistance test time exceeds 96 h.It can be used as a water-based acrylic metal primer with high anti-corrosion performance requirements,and a water-based acrylic metal bottom coating Paint;The glossiness of the paint film prepared with AC.6 is 93.7 Gs,and the comprehensive performance is excellent.Considering the production cost,it can be used as a water-based metal top coat for steel structures;the paint film prepared with the water-based self-emulsifying modified acrylic resin AC.7 The hardness is H,and the comprehensive performance meets or exceeds the industry standard.It can be used as a waterborne acrylic metal anticorrosive primer for steel structures.3.Improved performance of cost-effective water-based metallic paint In order to enhance the performance of the water-based metallic paint prepared with the cost-effective AC.2,different pigments and fillers were selected and subjected to quantitative and qualitative tests.The following results were obtained: 4% kaolin was added,the hardness increased to H;the composite iron-titanium powder and zinc phosphate were 3 : 5 When compounded,the salt spray resistance test time is prolonged by 24 hours;composite zinc phosphate replaces zinc phosphate,and the hardness is increased to H;modified zinc phosphate replaces zinc phosphate,and the salt spray resistance is improved;6% ultra-phosphor zinc white is added,Corrosion resistance is enhanced;8% iron oxide red is added,and the comprehensive performance meets or exceeds industry standards;1.5% strontium chrome yellow is added,the paint film has the best performance-water resistance test exceeds 720 h,salt water resistance exceeds 96 h,Acid resistance is more than 36 h,alkali resistance is more than 12 h,and salt spray test is more than 120 h.The improved performance of cost-effective water-based acrylic metallic paint can be used in the corrosion and rust prevention of steel structures.4.Preparation and performance of water-based epoxy metal primerAccording to the basic formula,the waterborne epoxy metallic paint prepared by cross-linking a variety of resins and curing agents was tested.The performance of the coating was tested according to HG/T 4759-2014 "Waterborne Epoxy Anticorrosive Coatings",and the experimental results were determined.The water-based epoxy resin and curing agent are EP.1+CU.1.5.Formula optimization of water-based epoxy metallic paintQuantitative and qualitative tests were performed on some experimental raw materials,and the basic formula was optimized.After testing,the comprehensive performance meets or exceeds industry standards,and can be used as a water-based metal anticorrosive primer for construction machinery.6.Preparation and performance of waterborne polyurethane metallic paint and composite coatingUse high hydroxyl value waterborne hydroxypropyl dispersion PO.2 with isocyanate curing agent CU.6,low hydroxyl value PO.1 with CU.5,and test the film properties according to HG/T 4761-2014 "Waterborne Polyurethane Coatings".After testing,the mechanical properties of the two paint films exceed industry standards.PO.1 and CU.5 have a cross-linking reaction gloss of 92.6 Gs,and PO.2 and CU.6 have a cross-linking reaction gloss of 78.2 Gs,both of which can be used as water-based Metal anticorrosive finish.Combining cost performance and gloss,it is determined that PO.1 water-based hydroxypropyl dispersion with low hydroxyl value is cross-linked with CU.5 isocyanate curing agent to prepare water-based metal finish.The two-component epoxy primer and two-component polyurethane topcoat are used to prepare a composite coating,and the performance is tested according to HG/T4761-2014.After testing,the salt spray resistance test exceeds 672 h,the water resistance test exceeds 144 h,and the acid resistance test 144 h has no abnormalities,all exceeding industry standards.Therefore,the composite coating has good comprehensive properties and can be used as a primer and top coat in the anti-corrosion of construction machinery. |
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