| Among organic coating adhesives,polyacrylate(PA)is one of the most important bonding materials due to its excellent adhesion,flexibility,and weather resistance.Aqueous PA coatings can penetrate corrosive agents such as water,oxygen,and destructive ions Cl-1,H+ into the substrate,restricting their use in anti-corrosion coatings.Epoxy resins have been widely used in many fields for their excellent adhesive properties,corrosion resistance,water resistance,impermeability and chemical resistance.However,there are still some disadvantages in the epoxy coating that are unfavorable for its application.Its impact resistance and resistance to media still need to be improved.Therefore,EP modified PA can combine the advantages of EP and PA to form a composite anti-corrosion coating.Therefore,this dissertation unfolds the research work and synthesizes a stable EP/PA composite latex.By adding the hyperbranched epoxy resin and increasing the content of linear epoxy resin,the barrier property of the film is improved,thereby increasing the film anti-corrosion properties.The main work of this paper is as follows:1)Using a proton transfer polymerization mechanism,a series of polyether hyperbranched epoxy resins were synthesized by changing the ratio of monomers,the monomer feed method,and the catalyst.When the ratio was A2:B3＝1:3,organic base TBAB as a catalyst,using a one-time adding method,you can get HBPE number average molecular weight of 2000g·mol-1,and Polymer dispersity index of about 2.2)Using the method of miniemulsion,synthesize water-based EP/PA composite latex,and study the influence of emulsification process and emulsifier.The result shows that the emulsification process selects the sequence of high-speed mixer and high-pressure homogenizer,and the emulsifier system selects A with the B compounding system,the particle size of the obtained water-based EP/PA composite latex is 226.1 nm,the conversion rate is 93.5%,and the calcium ion stability is greater than 5%.The latex can be left for about one year at room temperature.3)The HBPE was added to the water-based EP/PA composite latex to synthesize a water-based hyperbranched epoxy/linear epoxy/aery late three-component composite polymer latex by means of miniemulsion polymerization.At room temperature,you can place it for about a year.When the HBPE was added in an amount of 5%of the total monomer,the obtained water-based three-component composite polymer latex had a particle size of 211.9 nm,a conversion rate of 97.33%,and a calcium ion stability of more than 5%.4)A series of composite latexs with different amounts of HBPE as the matrix to add auxiliaries and pigments to make varnish and pigmented paint.In the medium-resistant test of varnish and pigmented paint coatings,the addition of HBP improves the barrier properties of the coating films,thereby improving the corrosion resistance.When the amount of HBPE added was 5%,the acid,alkali,salt,and water days of the varnish films were all more than 40 days,the acid resistance of the paint film was 35 days,the resistance to distilled water was 46 days,but the alkali water was in salt water more than 62 days.5)A series of latexs with different content of linear epoxy resin in the complex latexs are used as matrix to add auxiliaries and pigment fillers to formulate varnish and pigmented paint.As the content of linear epoxy resin increases,the barrier properties of varnish and pigmented paint become higher,and the anti-corrosion performance becomes better.In the resistant media of the varnish coating,when the epoxy resin content is 80%,the paint film has more than 59 days of acid,alkali,salt,and water resistance.The soaking days of the pigmented paint in the acid-base salt all exceeded 62days. |
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