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In the plating process, the addition of additives can improve the quality of the plated layer. Suitable additives can make the plated layer more resistant to corrosion while obtaining a flat and bright plated layer. In this paper, the effects of four types of additives on the corrosion resistance of electroplated zinc–nickel alloy plating were investigated, and the process conditions such as current density and plating time were determined by Hull tank experiments and small tank experiments. The effects of the content of various additives and different additives on the corrosion resistance of the plating layer were investigated, and the optimal additives were the compound combination of BH-A and BH-B at 6 mL/L each. Under the same plating process conditions, the effect of adding suitable additives and not adding additives on the corrosion resistance of the plated layer was investigated. The findings revealed that, in comparison to the plating solution sans additives, the integration of appropriate additives not only enhanced the deposited layer's corrosion resistance but also led to a decrease in grain size, increased uniformity, density, and achieved a higher degree of flatness. The results indicate that, in contrast to the plating solution without additives, the inclusion of suitable additives not only enhances the corrosion resistance of the resulting plated layer but also generates a smaller grain size, uniformity, density, and higher flatness in the deposited layer. [ABSTRACT FROM AUTHOR]

The influence of four complexing agents on corrosion resistance of Zinc-Nickel (Zn-Ni) alloy coating was investigated. The current density and plating time were determined by Hull and rectangular tank experiments. The effects of triethanolamine, potassium sodium tartrate, tetraethylenepentamine and sodium citrate on the properties of iron-based Zn-Ni alloy coatings were studied under the same electroplating process. The surface morphology, structure, elemental composition and corrosion resistance of Fe-base Zn-Ni alloy coatings with different complexing agents were analyzed. The surface and morphology of the coating were analyzed by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The anticorrosive properties of the coating were evaluated by electrochemical electrode and electrochemical impedance spectroscopy (EIS). The self-corrosion current density of triethanolamine is 2.927e-005A·cm−2, the rate of corrosion is minimal, rendering the material highly resistant to corrosion; the surface remains flat and exhibits a dense texture. The content of potassium, sodium, Zn and Ni in tartrate increased, thus reducing the corrosion resistance and flatness of the coating. The self-corrosion current density was 9.400e-005A·cm−2. The surface was rough and uneven, and there were a large number of large concave and convex defects. The complexing agent enhances the adhesion and corrosion resistance of the coating, improves the optical and mechanical properties of the coating, adjusts the durability and stability of the coating, increases the crystal packing density, increases the coating thickness, improves the adhesion with the substrate interface, and optimizes the uniformity of grain distribution. These factors are the key factors that determine the corrosion behavior of Zn-Ni coatings. In the process of electroplating, the addition of complexing agent can improve the quality of the coating, and suitable complexing agent can obtain smooth and bright coating at the same time, make the corrosion resistance of the coating higher. [ABSTRACT FROM AUTHOR]

In order to improve the flame retardancy of polystyrene (PS), a phosphorus and nitrogen comonomer, named AC2NP2, was synthesized and then incorporated into various amounts of PS by seeded emulsion polymerization. The modified methacrylate (AC2NP2) was used as the core phase, the styrene as the shell phase, then flame-retardant effect copolymers with core-shell structure were prepared successfully. The particle size was ranged from 40 to 60 nm, and the structure and properties of the copolymers were characterized in detail. Notably, despite a few amounts of the AC2NP2 units in the copolymers, all the copolymers exhibited significantly enhanced thermal stability and reduced flammability as compared with pure PS. Furthermore, from differential scanning calorimetry test, it was observed that the glass transition temperature was tinily influenced with the incorporation of commoner. The incorporation of P-N comonomer into PS backbone did not lead to negative effect on the glass transition behavior of PS. [ABSTRACT FROM AUTHOR]