Container Bottom Paint

Being a heavy anti-corrosion paint, container paint should have excellent performance both in application and in corrosion protection. Coal-tar asphalt was c.hosen as the main film-forming resin in the development of the paint for container bottom. In this paper, the emphasis was laid on the study on the modification of the i-sphait, additionally, the design of the solvent and paint formula, the rehological and anti-corrosive characteristic of the paint were described.SBS and modified epoxy resin were mixed with the asphalt to form polymer alloy, in order to improve the coal-tar asphalt which yields at high temperature and :>ristles at low temperature. The feasibility of the mixture was discussed through thermodynamic and kinetic factors, and the micro-structure of the modified asphalt was observed under a fluorescence microscope, the observed micro-structure showed that the mixed resins i e, SBS802 and modified epoxy resin were Jispeised evenly in the continous asphalt phase. The modified asphalt has much mprovement upon the ordinary asphalt, especially on its physical performance, such s soilening point, adhesive force, impact resilience and flexibility at low temperature. Therefore, the modified asphalt can be used as the film-forming resin ibr container paint.There are three decisive factors in the formula of the mixed solvents, i.e. solubility parameter volatile rates and the balance among solvents. This article described a test of the range of solubility parameters and a solvent formula consisting of different percentage volume concentration of Benzene, Dimethyl benzene, Cyclohexanone and Butyl akohol aided by computer programe. This solvent formula can fulfil the demands of container paint, such as: drying, levelling. the design of solvent formula aided by computer can substitute the traditional expentical formula design and avoid the trouble in artifical design..Silica, Mica, Zinc oxide, Iron oxide, Iron oxide black, Compound zinc ;inosphate were selected as pigments for the container paint. A formula at the highest overall score was chosen from the L16(54) perpendicarity experiment as the basic point formula, evaluated by the standard of mechanic and anti-corrosion performance. 1% bentonite, 2% modified polyamide wax, 1% DA-325, 0 5%modified stlicone 6500 and 1% dipheny ketone were added to the paint solvent and stirred at high velocity. These additives can improve the paint performance in the course of manufacture, store or application. Additionally, the component of the grinding fluid and the thinner were discussed in the design of the manufaturing process,The sorts and concentration of the thixotrope are the decisive factors of the thixotropic performance of the paint. 1% bentonite and 2% modified polyamide wax were dispersed to the paint system as thixotropic agents, and the thixopic performance of which was evaluated with thixotropic circular cirve and casson equation. The result indicated that the paint with these additives was capable of anti-sagging and leveling, which was painted over SOOjim wet film thickness.Corrosion resistance is one of the critical technical targets for the container paint Anti corrosive pigments, PVC, and film-forming resin are all the controlling factors of the corrosion. Through the immersion experiment in 5% NacK 3% NaOH> 3% H2SO4 solution, It was found that the coating had high anti-corrosion performance when the content of the modified epoxy resin was less than 8%, and the content of anti-corrosive pigment was over 50% of the total weight of pigments. It was also found that the content of SBS had less effect on the coating's anticorrosive performance in NaCl, weak acid or weak base solution separately. Modified Aluminum tropolyphosphate and Compound zinc phosphate had the same anticorrosive performance as zinc tetroxychromate and had better anticorrosive over Mica ferric oxide, Aluminum tripolyphosphate. The organic coating can avoid the diffusion of water, but the water diffusion can't be controlling step of corrosion until the coating thickness...