General knowledge of coating: development and application of polyaspartic ester coating

The key points are: firstly, polyaspartic acid ester is used as active diluent in traditional two-component polyurethane solvent coating formulation Polyaspartic ester has relatively low viscosity and good miscibility with hydroxypolyester and acrylic resin Therefore, it is an excellent active diluent for high solid content polyurethane coating, which reduces VOC value of high solvent system Table 1 Comparison between polyaspartic ester coating, polyurea coating and common polyurethane coating Project polyaspartic coating poly 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 Home of coatings news: first of all, polyaspartic acid ester is used as active diluent in the traditional two-component polyurethane solvent coating formulation Polyaspartic ester has relatively low viscosity and good miscibility with hydroxypolyester and acrylic resin Therefore, it is an excellent active diluent for high solid content polyurethane coating, which reduces VOC value of high solvent system Table 1 Comparison items of polyaspartic acid coating, polyurea coating and common polyurethane coating: polyaspartic acid coating, polyurea coating, polyurethane coating, aging resistance, aliphatic, better UV resistance and color retention, generally poor UV resistance and color retention, generally poor UV resistance and color retention, generally poor UV resistance and color retention, film thickness ranging from 375 μ m to medium, up to 2 The VOC emission of 550 μ m film is close to 0 at about 50 μ m, but it is usually solvent type, which is about 0 solvent type There is a certain VOC emission curing speed that can be quickly solidified according to the change of curing speed required by the application When catalyzing, polyaspartic ester with medium curing speed is the main reaction component of isocyanate, and a coating system with low VOC or close to zero VOC emission is obtained Due to the unique molecular structure of polyaspartic acid ester, the curing rate can be adjusted by selecting different kinds Selection of fast curing coating can meet the requirements of users; fast curing system can improve construction efficiency, with thick film, low temperature curing, wear resistance, corrosion resistance and other properties 2 fast curing anti-corrosion coating system polyaspartic ester anti-corrosion coating is formed by the reaction of polyaspartic ester and common aliphatic isocyanate (such as HD I trimer) It has the characteristics of high hardness, stable color, good wear resistance and weather resistance It is suitable for anti-corrosion finish on steel The double coating polyaspartic ester coating system has good anticorrosion performance, which is composed of zinc rich wet curing polyurethane primer and polyaspartic ester top coat The formula of one component zinc rich moisture curing polyurethane primer is shown in Table 2, with solid content of 70%, application period of 2 h, surface drying time of 1-2 h, spraying construction, film thickness of 75-125 μ m; the formula of two-component polyaspartic acid ester finish is shown in Table 3, with solid content of 80%, application period of 1-2 h, surface drying time of 1-2 h, spraying construction, film thickness of 150-250 μ M M See Table 4 for the performance of two-component polyaspartic ester top coat Table 2 one component moisture curing zinc rich polyurethane primer NOK = "F" O: CO necttype = "rect" gradientshapeok = "t" > in this study, the fast curing double coating polyaspartic ester coating system is adopted The film thickness and anti-corrosion performance of the system can reach the standard of the common triple coating heavy-duty anti-corrosion system The rapid recoating method is adopted, that is, the primer is directly sprayed on the sandblasted steel plate After the primer is applied for 2 hours, the top coat is applied and the corrosion resistance of the system is tested At the same time, the epoxy / acrylic polyurethane double coating system was used as a comparative study The thickness of the whole coating is 150-200 μ m, which is lower than the maximum thickness of polyaspartic acid ester double coating system This is because when higher film thickness is used, the usual epoxy / acrylic polyurethane system will have bubbles In order to compare the performance of the two coating systems, the film thickness of polyaspartic ester coating system is consistent with that of epoxy / acrylic polyurethane system Table 3 performance construction of two-component polyaspartic ester topcoat Table 4 performance construction of polyaspartic ester topcoat, the interlayer construction interval of epoxy / acrylic polyurethane system is determined according to the coating manufacturer's regulations For example: the acrylic polyurethane top coat shall be applied 24 hours after the primer is applied In addition, the anti-corrosion research was carried out under different environmental conditions for 24 hours: 4 ℃ / 40% RH, 21 ℃ / 50% RH, 32 ℃ / 80% RH, and then cured at 21 ℃ / 50% RH for 2 weeks The samples cured at 21 ℃ / 50% RH were subjected to artificial accelerated aging test The salt spray aging test (ASTM b-117) and cyclic climate aging test (ASTM d-5894) were used respectively The standard chart index of ASTM d714-87 was used to evaluate the bubble grade, and 1-10 was used to express the bubble size: 10 - no bubble; 8 - the minimum size of dense visible to the naked eye The frequency of bubbles is divided into four levels: D - dense; MD - medium dense; m - medium; F - few See Table 5 and table 6 for the aging results of salt spray and cyclic climate respectively Table 5 salt spray aging test (ASTM b-117) table 6 cyclic climate aging test (ASTM d-5894) it can be seen from table 5 and table 6 that the coating has good corrosion resistance In addition, the results of anti-corrosion test of solidified samples under different conditions are basically the same Conclusion the two-component polyaspartic ester coating can replace the traditional solvent polyurethane coating Through rapid solidification, the construction efficiency is improved Polyaspartic coating can also provide a thicker coating (up to 375 μ m) than traditional polyurethane finish, which can reduce the number of coatings and improve the construction efficiency It has yellowing resistance and good weather resistance, and is usually used as anticorrosive finish The accelerated aging test shows that the polyaspartic ester coating has basically the same corrosion resistance as the epoxy zinc rich / acrylic polyurethane coating system If the film thickness is increased, better anticorrosion effect will be achieved The results show that the anticorrosive performance of the coating is comparable to that of the current three coating heavy-duty anticorrosive coating system In addition, the coating recoating interval is 2 hours, which improves the working efficiency Generally, the whole construction time is 4-6 hours, while the epoxy zinc rich / acrylic polyurethane coating system needs 30-36 hours 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,