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The paper aims to discuss the evaluation of anti-corrosive efficiency of conducting polymer, polypyrrole in water borne epoxy-polyamine coatings.

Polypyrrole (PPy) is synthesised by chemical oxidative polymerisation. The synthesised PPy is characterised by employing FT-IR, XRD, SEM and EDX analysis. The coatings are formulated using water borne epoxy cross-linked with aliphatic polyamine adduct and the effect of PPy on corrosion prevention is studied. PPy was used as anti-corrosive pigment in concentration varying from 1 to 5 wt.%. In addition to anti-corrosive property; mechanical properties, chemical resistance and weathering properties of the coatings containing PPy are studied, thereby obtaining a wholesome data about the quality and performance of these coatings.

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. Higher percentage loading of PPy (beyond 3 per cent) proves to be disastrous, as extended percolation networks are formed which results in rapid intense corrosion leading to fast coating breakdown.

The anti-corrosion property of the coating can be tested by means of atmospheric exposure such as Florida test which produces a real time evaluation of the anti-corrosive nature of the coating at natural condition rather than accelerated weathering, thereby providing more reliable performance data for intended application purpose.

The results find application in anti-corrosive/performance paints for industrial application.

This research paper presents the results of anti-corrosion behaviour of PPy in water borne epoxy-polyamide coating. Based on this result, a highly effective anti-corrosive coating can be formulated by the addition of small percentage of PPy in combination with other conventional pigments, thereby enhancing corrosion protection. But care must be taken so as to avoid formation of extended percolation network of PPy which leads to rapid coating breakdown.

Polymeric systems based on polyesteramides (PEA) are high performance materials, which combine the useful properties of polyester and polyamide resins, and find many applications, most importantly as protective surface coatings. The purpose of this paper is to characterise and evaluate new modified anti‐corrosive PEA resins for use in protective coating formulations.

In the study report here, new modified PEA compositions were prepared and evaluated as vehicles for surface coating. The PEA resins were obtained by means of a condensation polymerisation reaction between phthalic anhydride (PA) and N,N‐bis‐(2‐hydroxyethyl) linseed oil fatty acid amide (HELA) as the ingredient source of the polyol used. The phthalic anhydride was partially replaced with N‐phthaloylglutamic acid NPGA as the ingredient source of the dibasic acid. The structure of the resin was confirmed by FT‐IR spectral studies. Coatings of 50±5 μm thickness were applied to the surface of glass panels and mild steel strips by means of a brush. The coating performance of the resins was evaluated using international standard test methods and involved the measurement of phyisco‐mechanical properties and chemical resistance.

The tests carried out revealed that the modified PEA based on N‐phthaloylglutamic acid (NPGA) enhanced both phyisco‐mechanical and chemical properties. Also, the resins were incorporated within primer formulations and evaluated as anti‐corrosive single coatings. The results illustrate that the introduction of N‐phthaloylglutamic acid, within the resin structure, improved the film performance and enhances the corrosion resistance performance of PEA resins.

The modified PEA compounds can be used as binder in paint formulations to improve chemical, physical and corrosion resistance properties.

Modified PEA resins are cheaper and can be used to replace other more expensive binders. These modified PEA resins can compensate successfully for the presence of many the anticorrosive paint formulations and thus lower the costs. The main advantage of these binders is that they combine the properties of both polyester and polyamide resins based on nitrogenous compound, are of lower cost, and they also overcome the disadvantages of both its counterparts. Also, they can be applied in other industrial applications.

This work investigates the single substrate (SS) technique for obtaining potential and current noise data for electrochemical noise measurement (ENM) analysis. The technique uses a single substrate element, and has shown promise as a useful application for use in the field. The traditional two working electrode approach of obtaining data is hindered by the fact that two electrically isolated substrate elements are required to act as working electrodes. The SS technique addresses this problem, theoretically enabling ENM to be made on any structure using just one electrical connection to the metallic substrate. Results are presented for anti‐corrosive organic coating systems intended for marine applications that have very high resistance values (> 1 × 10⁹ohm‐cm²). In addition data obtained from previous work that looked at a single coat anti‐corrosive primer after a short period of time in immersion and giving R_n values of around 1 × 10⁸ohm‐cm² are presented. Good agreement is seen between values of R_n obtained from the traditional two working electrode method and those obtained from the single substrate technique over both ranges of resistance.

The development of ‘Epikote’ resins, which have become freely available in Britain during the past two years, has led to important advances in the formulation of anti‐corrosive coatings. The resins, produced by Shell, are of the epoxide type and represent a new development in the synthetic resin field. They are based on two chemicals, epichlorhydrin and diphenylolpropane, derived from petroleum.

A new factory for the automatic curtain coating of paint has recently been opened by Autocoat Ltd. at Browells Lane, Feltham. Claimed to be the first such factory in Great Britain, it is capable of employing a great many of the anti‐corrosive coatings on a vast variety of substrates.

THE Glacier Metal Co Ltd manufacturers three dry bearing materials, namely Glacier DU, DQ and Deva Metal.

In quite a number of the American states strict regulations forbidding the use of leaded coating materials have been passed in recent years. As a matter of fact, there is nothing new about the fact that lead compounds are toxic. Centuries ago, sugar of lead (lead acetate) had been a well‐known “legacy powder” used by poisoners. Its sweet taste and slow effect made it particularly suitable for such purposes. Thus, in Germany, a law was passed as early as in 1887 prohibiting the use of leaded paints in packing material for foodstuffs and toys. In all civilized states ordinances exist which protect workers in contact with such paints from lead poisoning.

The purpose of this paper is to evaluate the water vapour permeability and mechanical properties of a solventless epoxy – nano‐platelet nano‐composite system compatibilised with an amino‐silane.

The performance of a nano‐platelet reinforced coating composite was studied with reference to the water vapour permeability and mechanical properties. The effect of addition of coupling agent on these properties was also studied.

The addition of nano‐platelets to the solventless epoxy system resulted in an increased water vapour permeability which was reduced on the addition of coupling agent. The talc‐based films showed a better performance as compared to the montmorillonite based coatings. The mechanical properties of the films increased though the addition of coupling agent showed a larger increase. The gloss of the coatings was compromised on addition of nano‐particles. Comparing coupling agents, the primary amine based silane showed better performance and lower tactoid formation as compared to the secondary amino silane based coupling agent.

The addition of nano‐particles to solventless and other eco‐friendly coatings needs to be studied further. Various other coupling agents could be studied to further improve the performance of these coatings.

The formulation developed could be used to reduce the water vapour permeability and performance of solventless epoxy coatings, which could be used as anti‐corrosive coatings.

The study of performance of nano‐particles in solventless epoxy coatings and their effect on water vapour permeability could increase performance of these reduced VOC coatings.

To give a brief review discussing all areas of technology is an impossible task — however, many engineers, consultants etc., have to decide from a mass of literature what system to use for a particular project. The author's company give a free world wide service in technical advice in the following areas — marine, tank lining, pipe coating, offshore rigs and structures, jetties, dock gates, bridges, chemical plants and all other structures exposed to severe conditions. The following general comments should provide a basis for consideration.

Corrosion technology in the years leading up to the Sixties developed at a relatively slow pace but the past ten years has seen a fast increasing rate of progress. There is today a new awareness amongst industry of the need to protect capital equipment and to maximise the life expectancy of costly industrial, petrochemical and maritime installations. Almost without exception, production companies now appreciate that corrosion prevention is cheaper than cure. Unprotected surfaces are an anachronism and no responsible engineer would allow erosion of effectiveness of productive plant for the want of the application of a specialised coating system. Anti‐corrosive protective coatings applied at construction stage can ensure that the full useful life cycle is achieved and the day of replacement postponed often far beyond the forecast date.