| This paper mainly was the study of synthesis of one-component water-basedepoxy resin coating and the adhesion of organic coatings with Ti/steel clad plate. Itcould be divided into two parts.The1st part: Epoxy coating has many advantages such as strong adhesion,excellent resistance against acid, alkali and solvent, which plays an important role inanti-corrosion coatings. However, two-component epoxy resin coating which iswidely used has many drawbacks, such as limited use time, being error-prone, aminecuring agent being expensive and easily decomposed in light etc. A one-componentwater-based epoxy resin coating was synthesized which used water as solvent and canbe cured to form film without a curing agent. The key to synthesize the coating waspreparing a reactive quaternary ammonium salt which was prepared by3steps:etherification reaction of epoxy resin with unsaturated fatty acid, ring-openingreaction between epoxy resin and amine and quaternization of epoxy-aminocompounds with halo-hydrocarbons. This paper studied the reactions through keepingthe tracks of epoxy value, amine value and acid value, comparing the performance offilms and analyzing changes of material elements before and after reaction by NMRI,and concluded the optimum reaction conditions and ratio of reactants: unsaturatedfatty acids: epoxy=0.5:1, the esterification temperature as180℃, using linseed oilfatty acid as unsaturated fatty acids, and the quaternization reaction temperature as45℃.Adding acid and water to the quaternary salt, successively, the aqueous amine asa chain extender reacted with epoxy resin to get the one-component water-basedepoxy resin coating. We summarized the chain extension reaction in aqueous is in linewith the characteristics of emulsion polymerization, and concluded the optimumreaction conditions and ratio of reactants by keeping the tracks of the changes ofparticle size, epoxy value and acid value and comparing the performance of films etc:T=70℃, pH=6.5, reactive quaternary ammonium salt: epoxy=1.1:1.One-component water-based epoxy resin coating has many advantages such as dryingat low temperature, safe and nontoxic, easy to use, storage stable etc.The2nd part: This paper studied the surface structure of Ti/steel clad plateprepared by spraying Ti to the surface of steel plates in high-energy and tested thecombination with organic coatings. The Ti/steel clad plate effectively integrated the excellent resistance to corrosion of Ti and the structure strength of steel, in addition,it was optimum in cost. However, it was inevitable to yield pores and cracks. Thestructural defects not only affected the corrosion resistance of the sprayed Ti film, butalso reduced the mechanical behavior. Therefore, some kinds of representativeorganic coatings in market and nano-modified acrylic coating were used to conductsealing treatment. We compared the sealing results of different organic coatings bymeasuring the surface tensions of coatings in liquid state and the adhesion of organiccoatings with Ti film and observing the cross-section of the junction of organiccoating and sprayed Ti film by SEM. The results showed that the surface tension ofnano-modified acrylic coating is20.64mN·m-1, which penetrate to the pores andcracks of Ti film and had stronger adhesion with Ti film which is19MPa. Moreover,EIS and salt spray tests were conducted to the organic/Ti/steel clad plates to comparetheir resistances to corrosion. The results showed that nano-modified acryliccoating/Ti/steel clad plates had higher resistance to corrosion. |
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