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Water soluble epoxy‐amine adducts were prepared by reacting epoxy resin with diethanolamine in different molar ratios. These adducts were further partially esterified with linseed oil fatty acids. Aqueous coating compositions for cathodic electrodeposition were prepared from epoxy‐amine adducts and esterified epoxy‐amine adducts separately. Film properties of cathodically electrodeposited coatings were evaluated and studied. It was observed that coatings based on 20% and 30% esterified epoxy‐amine adducts had good overall film properties.

Fluorinated silicon polymers are expected to be adopted in specific coatings to afford outstanding advantages, such as high chemical and photochemical resistance, low surface tension and low refractive index. The modified acrylate resin is prepared via solution polymerization of fluorine and silicon monomers, acrylate monomers and other functional monomers. The purpose of this paper is that the fluorine and silicon monomers such as vinyltriethoxysilane (VTES) and hexafluorobutyl methacrylate (HFMA) and some cheap monomers such as styrene are used to prepare the cationic acrylic resin.

The fluorine and silicon modified cationic acrylic resin is prepared via solution polymerization technology, which uses butyl acrylate (BA), methyl methacrylate (MMA), styrene (St), HFMA, VTES, dimethylaminoethyl methacrylate (DMAEMA) and hydroxypropyl methacrylate (HPMA) as the co-polymerized monomers, propylene glycol monomethyl ether (PGME) as solvent and 2,2-Azo-bis-iso-butyronitrile (AIBN) as the initiator to create a resin to introduce the Si–O and C–F into the polymer chains. The cathodic electrodeposition (CED) coatings were prepared by mixing the synthetic resin and blocked isocyanate.

The influence of the amounts of HFMA and VETS on the resin and the resultant CED coatings is investigated in detail. The optimum amounts of HFMA and VETS are obtained, which is 7–8% and 4–5%, respectively. The hydrophobicity and the acid and alkaline resistance of the film are improved when VETS and HFMA are introduced to co-polymerize with other monomers.

The fluorine and silicon monomers such as VTES and HFMA and some cheap monomers such as styrene, which are used to prepare the cationic acrylic resin, are seldom reported in the open literature.

The purpose of this paper was to prepare a fluorinated acrylate resin, which would be synthesised via solution polymerisation of fluorinated monomer, acrylate monomers and other functional monomers. Relevant characterisation and application studies were also carried out. Fluorinated polymers are expected to be adopted in specific coatings to afford outstanding advantages, such as high chemical and photochemical resistance, low surface tension and low refractive index. At present, fluorinated cathodic electrodeposition (CED) coatings are attracting the attention that they deserve and seldom reported.

Cationic fluorinated acrylic resin was successfully prepared by solution polymerisation of dodecafluoroheptyl methacrylate, butyl acrylate, methyl methacrylate, dimethylaminoethyl methacrylate and methacrylic acid initiated by 2,2,-azo-bis-iso-butyronitrile in a solvent of butyl cellosolve. The resultant resin was neutralised with acetic acid. The CED coatings are prepared when moderate amounts of blocked isocyanate and distilled water were added into the resultant resin.

The hydrophobicity of the film is improved when the fluorinated monomer is introduced to co-polymerise with other monomers. The optimum conditions of preparing the resin are as follows: the amount of azodiisobutyronitrile is controlled with the range of 3.0 and 4.0 per cent; the amine value of the resin is 70 mg KOH/g; the hydroxyl value of resin and mole ratio of hydroxyl to isocyanate is 60 mg KOH/g and 1.0/1.0, respectively; the degree of neutralisation of the resin is within the range of 35 and 40 per cent.

The cationic fluorinated acrylic resin can be used to be the binder of CED coatings, which can be applied to electrodeposition finishing for high demand of exterior decorative and weather resistance, such as hardware, accessories, office furniture and so on.

The cationic fluorinated acrylic resin was successfully prepared by solution polymerisation. The hydrophobicity of the film is improved.

The purpose of this research is to prepare a dispersion resin with good dispersity and a colour paste with good stability. At present, the colour paste is being prepared using the pigment dispersion resin which has the group quaternary ammonium. The dispersion resin prepared has good dispersity of pigment and extender. However, the stability of storage and construction of the colour paste is relatively poor, which has a negative influence on the application of cathodic electrodeposited (CED) coatings. However, the detailed investigation on the dispersion resin and the stable colour paste has not been reported.

Three steps are adopted to prepare the dispersion resin, that is blocking toluene diisocyanate (TDI), quaternary ammoniation of blocked TDI and ring opening of epoxy resin. The resultant dispersion is used to prepare the colour paste. The factors, which have an influence on the dispersity of the dispersion resin and stability of the colour paste, are optimised.

The typical recipes of preparing the dispersion resin and the resultant colour paste are obtained. The dispersity of the dispersion resin and stability of the colour paste are good based on the typical recipe. In addition, the film of the CED coating is smooth, dense and hard when the colour paste is used in the CED coating.

The dispersion resin can be used to prepare a colour paste, which can be used in the CED coatings. In addition, it also can be applied as a binder of coatings and adhesions.

The factors, which have an influence on the dispersity of the dispersion resin and stability of the colour paste, are studied in detail. The typical recipes of preparing the dispersion resin and the resultant colour paste are obtained. Based on the typical recipe, the dispersity of the dispersion resin and stability of the colour paste are good.

Without customers, no business can exist. How a customer is treated — in the broadest sense — determines whether it maintains its relationships with a supplier and, therefore, whether the supplier has a future.

Thin coatings are of great importance to minimize corrosion attack of steel in different environments. A review of recent work on electrodeposition and corrosion performance of Zn-Ni-based alloys for sacrificial corrosion protection of ferrous substrates is presented. The purpose of this study is to provide a systematic comparison of the corrosion resistances of Zn-Ni alloy coatings. The review contains key and outstanding comparisons of references for the period from 2007 to 2017. Binary and ternary Zn-Ni-based alloys were compared and contrasted to provide a good knowledge basis for selection of best coating system to steel substrates.

This article is a review article.

Zn-Ni-(X) alloys show great potential for replacing Cd metal in corrosion protection of steel substrates.

The research on plating of binary Zn-Ni alloys from aqueous electrolytes is now well advanced and these alloys show improved corrosion resistance compared to pure Zn. Pulse plated and compositionally modulated multilayer Zn-Ni alloy coatings showed enhanced corrosion properties compared to direct plated Zn-Ni coatings of similar composition.

The work on electrodeposition of Zn-Ni based alloys from ionic liquids is still scarce, yet these liquids show great promise in improving corrosion resistance and reducing coating thickness when compared to aqueous electrolytes. Advanced plating techniques in ionic liquids such as electromagnetic, compositionally modulated multilayer, pulse plating, ternary alloys and composites should be considered as these electrolytes avoid water chemistry and associated defects.