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The purpose of this paper is to study the curing mechanisms, anticorrosive properties and protective mechanisms of three kinds of amine curing agents applied in a new kind of light colored water‐borne epoxy antistatic anticorrosive paint.

Using light color‐conductive mica, titanium oxides and environmentally‐friendly anticorrosive pigments in the two‐component water‐borne epoxy system, the light colored water‐borne antistatic anticorrosive paint was prepared. The molecular structure and curing mechanisms of the curing agents was analyzed by Fourier transform infra‐red spectroscopy, and the influence of the curing agents on anticorrosive properties and protective mechanisms was studied by electrochemical impedance spectroscopy.

The paints cured by the modified amine curing agent possessed optimal integrated properties with a coating surface resistivity of 10⁶ Ω and the best anticorrosive performance.

A novel light colored water‐borne epoxy antistatic anticorrosive paint cured by the optimal curing agent could be used in corrosion protection for oil tanks to replace the traditional oil‐based antistatic anticorrosive paints.

There are many advantages to be gained from the use of water, rather than toluene, or other typical solvents used in the application of epoxide resin paint systems, as the comparison in table 1 shows:

The purpose of this paper is to synthesise new fatty dicarboxylic acid half ester (NFAHE) C25, which can be used as substitute to dimer/trimer acids commonly used (C36, 54) as basic raw materials for manufacture of polyamides for printing inks or as curing agents for epoxy paints and adhesives. This could be an economically viable synthesis by which the user could manufacture the finished products from relatively low cost raw materials.

Vegetable oils have several double bonds that undergo large number of reactions. Diels‐Alder addition is one of them. Dimer acids have been produced by using these double bonds by reaction of two fatty acid molecules. Maleic acid, acrylic acid has also been used for this purpose. Sorbic acid is a derivative of alcohol and hence a renewable raw material. It is relatively less used by the coating chemists due to its relatively limited availability due to restricted uses.

It was found that sorbic acid reacts easily with unsaturated fatty acids. Its solubility in fatty acids and esters is limited. A common solvent that can be removed easily after the reaction was necessary. Cyclohexanone was found to meet this requirement. The resultant half ester of dicarboxylic acid could be easily converted to polyamides for curing epoxies.

The user can manufacture his own dibasic/tribasic acid as a first step. As a source of methyl esters of fatty acids with iodine value about 110 to 130, vegetable oils such as soyabean oil can be used. Low value acid oils obtained from vegetable oil refining are also suitable. Bio diesel could be used directly. To account for large saturated fatty acids in bio diesel, corresponding trimer may be produced by appropriate addition of sorbic acid to fatty acid.

The process allows a manufacturer to develop low cost formulations for bulk products using simple chemistry that can be integrated in the existing process.

Hangers' epoxide enamel is an air‐drying twin‐pack material of which the major constituent is an epoxy resin solution pigmented with either titanium dioxide or other pigment according to the colour required. The minor ingredient, or curing agent, is a special blend of principally polyamide‐type resin which reacts with the epoxy resin after mixing. The mixed paint assumes its best characteristics some eight to sixteen hours after mixing, according to the prevailing temperature at the time. If the material is used soon after that period the resultant dry films will show their best properties.

Thomas Swan & Co Ltd have for many years offered a range of water dispersible epoxide curing agents. These products are better known as the Casamid 360 range — water soluble modified polyamide curing agents, consisting of the following range:

This paper aims to study the corrosion performance and physical properties of hybrid paint systems based on zinc-rich primer (ZRP) and to determine the optimum modification approach that guarantees the most overall performance enhancement for the developed coating films that have been fabricated based on the usage of ZRP.

Four different approaches were applied to enhance the corrosion protection performance and the physical properties of ZRP-based paint systems, namely, incorporation with TiO₂ pigment, introducing SiO₂ nanoparticles, usage of polyamide curing agent and application of epoxy base coating as a second layer. The physico-mechanical properties were examined using pull-off test, glossiness test, pencil hardness test and cross-cut adhesion tape test. Moreover, the contact angle measurement was used to study the wettability of the developed coated surfaces and the corrosion protection performances were evaluated by using electrochemical impedance spectroscopy and salt spray test.

The obtained results revealed the ability of a certain approach to enhance the physical and corrosion protection properties of the ZRP paint system. Moreover, developing an intact hydrophobic nanocomposite paint system based on the usage of ZRP as the host matrix and SiO₂ nanoparticles as the reinforcing agent was confirmed without altering the cathodic protection mechanism or the other desired characteristics of ZRP paint system.

The innovation of this work can be clearly observed by the ability to enhance the physical and corrosion protection properties of ZRP with four different approaches.

IN many of the industrial and other aggressive environmental conditions encountered today a synthetic, plastics‐type of paint system must be used, since traditional paints give poor and limited service. However, for these synthetic paints to be fully effective, they must be applied to more scrupulously prepared surfaces. The finer tolerances and more exacting application requirements of synthetic plastics‐type coatings, such as the epoxies, must be appreciated. Once these are understood it is not difficult to put the materials into use, where they give outstanding long‐term protection. Some of the physical, chemical and solvent‐resistance characteristics of the epoxy resin coatings can, of course, be attained with other synthetic paints, and all these materials have their place in the paint manufacturer's armoury. There are resins showing better flexibility and chemical or heat resistance than the epoxies, but the latter are outstanding in combining these and other characteristics to a marked degree—hence their fairly rapid user acceptance. There is inevitably over‐lapping in characteristics with other coatings, particularly the polyurethanes, and it is not claimed here that epoxy coatings can confer protection against all corrosive environments.

To prepare modified epoxy resins from resorcinol, cresol and phenol for improved adhesion and chemical resistance. To evaluate the properties of such modified epoxy resins.

Epoxy novolac resins (ENRs) were synthesised by condensing epichlorohydrin with novolacs based on different types of substituted phenols for improving adhesion and chemical resistance. Various compositions were made by incorporating different proportions of polyamide resin. The chemical and adhesive strengths of the conventional epoxy and the modified epoxy resins were characterised.

The modified ENR using substituted phenols showed significant enhancement of chemical and adhesive strengths over the conventional DGEBA resin. The modified ENR had an increased number of glycidyl groups (thus increased functionality) of resin, which was responsible for improved chemical and adhesive strengths over the conventional DGEBA resin.

The EPN resins used in the present context was synthesised from phenol, resorcinol and cresol and cured by polyamide resin of different amine values. Besides, it could be synthesised from phenolphthalein p‐aminophenol and p‐ter‐butylcatachol, etc.

The method developed provided a simple and practical solution to improving the adhesive and chemical resistance of cured epoxy phenol novolac resins.

The method for enhanced adhesive and chemical resistance of cured epoxy was novel and could find numerous applications in surface coating and adhesive.

The aim of this paper is to conduct a real time evaluation of polypyrrole as an anti‐corrosive pigment in epoxy polyamide coating.

This study deals with synthesis of polypyrrole (PPy) by chemical oxidative polymerisation in laboratory conditions. The synthesised PPy was characterised by employing FT‐IR, XRD, SEM and EDX analysis. Epoxy film of bisphenol type hardened with polyamide based curing agent was used as the binder. PPy was used as anti‐corrosive pigment in concentrations varying from 0 to 5 wt% in the coating. In addition to anti‐corrosive property, mechanical, chemical and weathering properties of the coating containing PPy were studied and compared with epoxy polyamide coating without PPy.

The result obtained through various tests showed that the coating with 1 and 2% PPy exhibited excellent weathering resistance, mechanical properties and improved chemical resistance.

The anti‐corrosion property of the coating can be tested by means of atmospheric exposure such as Florida test or by means of electrochemical impedance spectroscopy.

The results find application in anti‐corrosive paints for industrial application.

This research paper presents the results of anti‐corrosion behaviour of PPy in epoxy‐polyamide coating. Based on this result, a highly effective anti‐corrosive coating can be formulated by addition of small percentage of PPy in combination with other conventional pigments, thereby enhancing corrosion protection.

In part one of this article (August 1964) the author dealt with the general chemistry, curing characteristics and applications of two‐pack and coal tar‐epoxy coatings. Part two discusses other types of epoxies and describes their uses as corrosion‐resistant coatings and pipe linings.