溶剂型无机富锌底漆涂装施工技术

结合溶剂型无机富锌底漆的特性,介绍了其涂装施工技术和质量控制方法。     

Zinc–magnesium-pigment rich coatings for corrosion protection of aluminum alloys

Chromate (Cr(VI))-based pigments have been widely used for corrosion protective coatings because of their outstanding protection efficiency especially for aluminum alloy products. However, due to environmental issues associated with Cr VI, more and more requests are being made for alternative solutions. In the presented work zinc was modified by alloying with magnesium to achieve a combination of properties – cathodic protection and less reactivity during production, storage and application of the pigments. The magnesium content leads to a lowering of the electrochemical potential which allows the cathodic protection of aluminum alloys. zinc–magnesium pigments were prepared in different compositions with special attention to the intermetallic phases MgZn, Mg₂Zn₃, and MgZn₂. Pigments were produced and a zinc–magnesium rich coating was formulated and compounded. Pickled samples of AA 2024 unclad were coated and the corrosion behavior investigated. A durability of more than 10,000 h in salt spray test could be achieved.     

Time‐lapse lab‐based x‐ray nano‐CT study of corrosion damage

An experimental protocol (workflow) has been developed for time‐lapse x‐ray nanotomography (nano‐CT) imaging of environmentally driven morphological changes to materials. Two case studies are presented. First, the leaching of nanoparticle corrosion inhibitor pigment from a polymer coating was followed over 14 days, while in the second case the corrosion damage to an AA2099 aluminium alloy was imaged over 12 hours. The protocol includes several novel aspects relevant to nano‐CT with the use of a combination of x‐ray absorption and phase contrast data to provide enhanced morphological and composition information, and hence reveal the best information to provide new insights into the changes of different phases over time. For the pigmented polymer coating containing nominally strontium aluminium polyphosphate, the strontium‐rich components within the materials are observed to leach extensively whereas the aluminium‐rich components are more resistant to dissolution. In the case of AA2099 it is found that the initial grain boundary corrosion is driven by the presence of copper‐rich phases and is then followed by the corrosion of grains of specific orientation.     

Microwave Nondestructive Detection of Corrosion Under Thin Paint and Primer in Aluminum Panels

Detection of corrosion, under paint and primer, in various metallic structural components, particularly when used in moist and salty environments is an important practical concern. Moreover, nondestructive testing techniques that do not require paint removal are desired. Near-field microwave nondestructive inspection techniques, employing open-ended rectangular waveguide probes, have shown tremendous potential for detecting and evaluating the presence of corrosion under paint in steel substrates. The objective of this investigation has been to investigate the potential of these techniques for detecting corrosion under paint and primer in aluminum substrates. To accomplish this goal, an electromagnetic formulation, simulating detection of corrosion in layered structure using open-ended rectangular waveguide probes, was used to gain an insight into the functionality of measurement parameters such as the frequency of operation and standoff distance. In conjunction with this simulation, the dielectric properties of paint, primer, real and chemically produced aluminum oxide were measured in a wide range of microwave frequencies (2.6–18 GHz). The results showed that the dielectric properties of paint, primer and aluminum oxide are very similar to each other. Subsequently, the theoretical simulation was conducted in a wide frequency band (8.2–40 GHz). The overall result of the simulation effort was that higher frequencies and standoff distances of a few mm are more optimal for detecting thin corrosion layers under paint. Two specially prepared aluminum panels with induced areas of corrosion and surface pitting were produced as well. Using these panels and several phase sensitive measurement systems, experiments were conducted producing 2-D images of various areas of these panels. Images were produced at different standoff distances and at frequencies of 9, 11.725, 24.1, and 33.5 GHz. The overall results of the experimental investigation were extremely promising when detecting the thin regions of corrosion in these panels. This paper presents the approach and results of this investigation.     

Interphases in the Adhesive Bonding of Fluoropolymers

Strong and durable adhesive bonds may be made between polytetrafluoroethylene (PTFE) and either cyanoacrylate (CA) or epoxy adhesives, if the PTFE surface is modified by the use of a “primer” such as triphenylphosphine (TPP) or diaminodiphenylmethane (DDM). The primer mixes with the PTFE surface, and the modified surface is then capable of forming an interphase, tens to hundreds of nanometers thick, where interpenetration of the adhesive and adherend occurs. Using CA adhesives, PTFE/CA/PTFE block compression shear bond strength (ASTM D4501-85) of over 10 MPa can be achieved, with failure occurring cohesively. Initial work with epoxy adhesives indicates that the use of DDM primer gives adhesive bonds comparable in strength with those produced by modification of the fluoropolymer surface by sodium naphthalenide.     

环氧改性丙烯酸涂料的研制

采用特定的催化剂,制得环氧改性丙烯酸树脂,由其配制的环氧改性丙烯酸涂料既可作为装饰性面漆,也可作为中涂漆。介绍了环氧改性丙烯酸树脂及其涂料的制法和性能指标。通过红外光谱表征了环氧改性丙烯酸树脂的组成和结构。讨论了诸种因素对涂料性能的影响。     

锌粉含量对环氧富锌漆防锈性能的影响

研究了环氧富锌漆中锌粉含量对其漆膜防锈性能的影响。     

新一代水性无机富锌底漆的生产与施工应用

通过对高模数无机硅酸盐进行改性,使无机富锌底漆的质量与施工使用得到改善与提高,实现了水性富锌底漆与溶剂型富锌环氧底漆施工使用同样方便,性能更好,尤其是产品的环保性能和良好的防腐性能。     

笔记本电脑塑料外壳复合涂料体系的制备与研究

针对市场对笔记本电脑塑料外壳的涂装要求,介绍一种高性能、环保型水性塑料底漆及其配套用UV面漆的复合涂料体系。     

以硅溶胶为主要成膜物的水性木器透明底漆的研究

研究了硅溶胶凝胶的影响因素,选择匹配的高分子聚合物,对硅溶胶胶粒进行绑缚作用,协助硅溶胶成膜降低其刚性,考察其他助剂的协同作用,发挥出硅溶胶成膜后的特性,配制的水性木器涂料透明底漆具有硬度高、干速快、硬度建立快、初期抗压性好、耐水性优、附着力好、打磨性好等优势.