Emerald Group Publishing Limited
Copyright © 2008, Emerald Group Publishing Limited
Article Type: Conferences, training and publications From: Pigment & Resin Technology, Volume 37, Issue 4
Protective coatings “Protecting the Substrate & the Environment”
Amsterdam, The Netherlands, 24-25 October 2007
Proceedings contents ad abstracts
1. Novel high-solid systems based on silicone-epoxy hybrid resins
Dr Udo Schiemann, Christopher Howard, Anke Bartek and Markus Hallack, Degussa, Germany
Climate changes due to global warming and the greenhouse effect are likely to produce even more corrosive conditions in the future, because higher temperatures accelerate corrosion, and greater concentrations of carbon dioxide will increase carbonation rates and the acidity of rainfall. Corrosion is responsible for the failure of many systems and structures. Unchecked it can result in excessive maintenance and repair as well as system downtime and product contamination. Although this is primarily associated with metallic materials, in fact all material types are susceptible to degradation. Like taxes, corrosion is something we hope to avoid, but ultimately it is something we must learn to deal with.
Silicone-epoxy hybrid resins. Organic-inorganic hybrid coatings are of increasing interest to industry due to their potential widespread applications. The organic component in the matrix offers the advantages of mechanical toughness and adhesion while the inorganic component provides the coating with its hardness, thermal and UV-stability properties.
This presentation give a brief outline of the developments undertaken within our research laboratory of the different environmentally-compliant, cure, pre-treatment systems which offer alternatives to existing anti-corrosion coatings.
2. Waterborne epoxy technology and top performance: no longer a fairy tale?
Dominique Vandenberghe, F. Heine, P. Claeys-Bouuaert, K.Van Poppel, M. Rans, and A. Frederix, Hexion Specialty Chemicals, Belgium
Solventborne epoxy-amine technology has a long track record of excellent anti-corrosion performance in a wide range of protective, transportation and marine end-uses. Environmental legislation has been stimulating the development of high solids, solventfree and waterborne technologies. Initially the reluctance towards the use of waterborne technology for high demanding end-uses was strong as application technology and formulation knowledge needed to be developed and acquired. Nowadays, waterborne epoxy technology has already proven that it can replace solventborne technology without sacrificing final performance, even offering new end-use areas for epoxies. At the present time, main difficulty for formulators lies in selecting the “fit for purpose” available waterborne technology. This paper will cover the latest waterborne epoxy-amine product and formulation developments in order to be able to meet extensive end-use requirements such as: application on difficult substrates (metal and non-metal), thin film application, extreme cure condition (low and high temperatures), fast cure, etc. This paper will show that with waterborne technology we can meet these requirements without loosing performance and that waterborne technology and top performance are indeed no longer a fairy tale.
3. Radiation curable protective coatings: innovative and feasible solutions for the steel and aluminium industry
Dr Marc Heylen, Cytec Surface Specialties, Belgium
Radiation curing technology for industrial coatings has been established for decades in different applications (wood and paper coatings, plastic coatings, CD-DVD, optical fibers coating, electronics, etc.) and the advantages in terms of performance and processing are very well known. In metal applications, the use of radiation curing technology has been rather limited, and many technical obstacles discouraged the launch of new projects. In the last three years however, innovative and targeted developments at Cytec Surface Specialties, have lead to new and greatly improved radiation curable resins for metal coating applications. These innovative products belong to the eco-friendly technology of the future and address the specific needs of the metal coating industry.
4. Novel polyurethane spray elastomers with enhanced chemical resistance
Dr Christian Bruchertseifer and Gerhard Mueller, Dow Deutschland, Germany
Over the last decade polyurethane and polyurea spray elastomers and hybrids derived from them have found widespread acceptance in the protective coatings industry. However, in some industrial use scenarios like power generation, mining, refining, chemical processing, etc. the applicability of spray elastomers is limited to light to medium corrosion environments. In heavy corrosion environments where the protective coatings is exposed to severe chemical attack from strong acids or bases, hot oils or solvents, sometimes in combination with elevated temperatures, polyurethane and polyurea-based protective coatings are performing only marginally. Despite this lack in performance there is an interest by coating applicators to use a fast-set and fast-cure system which would enable them to finish a project in a much shorter timeframe than what is currently possible with incumbent protective coating technologies like epoxy, epoxy-novolac or vinylester. The objective of this study was to develop an approach to increase the chemical resistance of polyurethane hybrid spray elastomers without compromising processability or performance profile. To this end, hydrocarbon and natural oil polyol backbones were introduced to both reactive components. The incorporation produced a significant enhancement in chemical resistance. This was especially noteworthy for attack by acid medias and some solvents. It was furthermore found that varying backbones in A-(isocyanate) and/or B-(polyol resin) reactant produced an enhancing effect which surpassed the pure additive effect.
5. Developments in waterborne acrylic resins for low VOC industrial maintenance coatings
Dr Andrew Trapani, Anne M. Bacho, Gary R. Larson, Leo J. Procopio, William J. Rosano and Laura M. Vielhauer, Rohm and Haas Co., France
As environmental regulations become increasingly strict, manufacturers and end-users of both architectural and industrial coatings find themselves under increasing pressure to make and use paints with more advanced environmental profiles, such as those with lower VOC levels. Resin suppliers are challenged to design binders which not only allow lower VOC levels, but also maintain the expected high performance of traditional systems. This paper will discuss the development of several waterborne acrylic polymers for use in high performance, VOC-compliant coatings for industrial maintenance painting. These include a resin designed for corrosion-resistant, direct-to-metal coatings with VOC levels under 100 g/L, a self-crosslinking acrylic for clear coats to improve durability of pigmented basecoats, and an elastomeric acrylic designed for use in thick film (250-500 m), surface tolerant coatings for steel and concrete with VOC levels below 50 g/L. Formulations and coating properties will be described, along with comparisons to traditional, higher VOC waterborne and solventborne coatings.
6. Blistering of reactive resin coatings on concrete: causes and prevention
Lars Wolff, Professor M. Raupach and Dr Kidist Hailu, Institute of Building Materials Research, Aachen University, Germany
Epoxy resins have already been used for impregnation and coating of concrete parts since more than 40 years. The phenomenon of blistering of these coatings has been reported for the first time about 35 years ago: some weeks or months after application usually liquid filled blisters occur within or under the coating. In recent research projects the mechanisms of blistering were mainly described as osmotic transport processes in the contact zone between concrete and base coat. In an ongoing research project at the Institute of Building Materials Research of Aachen University, ibac funded by the German Research foundation DFG it could be shown that osmotic processes seem to be not involved in the effect of blistering. In the paper both the result of the latest research regarding mechanisms of blistering as well as different possibilities how to prevent blistering are represented.
7. Recent progress in the development of international standards for the surface preparation and painting of steelwork
Dr Nigel Whitehouse, PRA, UK
The performance of protective coating systems on steelwork is affected significantly by the surface cleanliness and surface roughness of the substrate immediately prior to painting. The principal factors known to influence this performance are: the presence of rust and mill scale, the presence of surface contaminants and the surface profile. Four International Standards (ISO 8501-ISO 8504) have been developed to provide methods of assessing these factors and to offer guidance on the techniques of surface preparation now available. To complement the surface preparation International Standards, ISO 12944 provides extensive information on the corrosion protection of steel structures by protective coatings. Recent developments in some of the most important parts of these five ISO Standards will be described.
8. Effect of soluble salt contamination of steel substrates on the performance of coatings
Paul McBain, International Paint Ltd, UK
Coatings performance can be seriously affected by the presence of soluble salts on the steel substrate that they are applied to. Coatings applied to steel surfaces that are contaminated with soluble salts would be expected to show a lower level of performance than the same coating applied to uncontaminated steel, with a high likelihood of sub-film corrosion and osmotic blistering occurring. This paper details a work program that has been carried out to attempt to rank a number of products which are usually used in immersion conditions with respect to how tolerant they are to soluble salt contamination and a comparison of their level of performance when they have been applied to soluble salt contaminated steel.
9. Soluble salt contamination on blast cleaned surfaces and the effect on the durability of subsequently, applied coatings
Peter J. Longdon and M. Bohm, Corus Group, UK
It is well known that residual water-soluble contaminants on steel surfaces, prior to protective coating application are detrimental to subsequent coating performance. Chloride/sulphate contamination levels of 0.3-0.6 micrograms cm−2 have been suggested  as the maximum that should be permitted and if levels this low are incorporated into standards documents, then this could result in expensive and unnecessary cleaning operations prior to the coating of steel surfaces. Corus R,D&T has undertaken an RFCS project (in collaboration with ProfilArbed, Max Plank Institute For Iron Research (MPIE) and CENIM) in order to assess the impact of water-soluble salt contaminants at steel/coating interfaces and to establish realistic working limits. Typical industrial coating systems incorporating elements such as zinc silicate primers, fusion bonded epoxies, glass flake epoxies, micaceous iron oxide (MIO) primers, glass flake epoxy polyamides and zinc rich systems, were evaluated. Acceptable contamination levels of 10-40 micrograms cm−2 were typically observed.
Results also show that different coating systems can tolerate different levels of residual salt and the maximum tolerable salt value, for a specific coating system, depends on the exposure conditions (immersion, splash or atmospheric environments). In general, the safe limits suggested by this work  are 1-2 orders of magnitude higher than the more conservative assessment . These results are reinforced by the observation that the artificial doping of surfaces generates a greater “aggressivity” compared to natural contamination. Thus, the limits highlighted by this study are probably conservative. Basic mechanistic studies on model systems performed by MPIE support the idea of a critical contamination level, below which little effect on durability is seen. One point of concern, however, is the impact on cathodic protection (CP), where the effect of sulphate, when either present alone or in combination with chloride, could be seen. CP is widely used (particular offshore) and this observation requires further investigation to fully understand the corrosion mechanism.
10. A multi-metal corrosion inhibitor with relevance to commercial surface preparation and coatings technologies
Dr Thomas C. Bedard, Lonza Inc., USA
A new water soluble quaternary ammonium compound, didecyldimethylammonium bicarbonate/carbonate (DDABC), has been evaluated as a corrosion inhibitor via standard electrochemical tests on steel and shown to be highly effective. At the proper dilution, the inhibitor migrates to the metal/solution interface and forms a mono-molecular film on the anodic sites. Preliminary evaluations reported here indicate that DDABC and its phosphate and glycolate anion derivates also exhibit a remarkable ability to improve the corrosion performance of several commercially relevant coatings including latex, alkyd and urethane e-coat systems when used either as a pre-treatment, sealing rinse, or formulated coatings additive. In some instances, DDABC provides corrosion performance enhancement in B117 salt spray tests of over 300 per cent and creep improvements of 60-75 per cent. Additional observations as an adhesion promoter, wetting agent and flash rust inhibitor are also reported.
11. Innovative polyamide technology delivering long overcoat window
Rob Rasing, Michael I. Cook and Neil T. Hunt, Air Products & Chemicals, The Netherlands
Growth in the global coating’s market and economies coupled with ongoing VOC requirements continue to bring challenges in high-performance protective coatings. Conventional high-solid polyamide technology for two pack epoxies provides outstanding performance and has become the industry standard for application in this sector. However, a major limitation to date is their limited re-coat window after applying the initial coating; this window or the time within which a second coating can be applied to result in good adhesion, has become of mounting importance. Increased geographical separation of the coating and fabrication processes has resulted in a requirement for primers with 3-6 months re-coat window. Conventional high-solids epoxies have only limited re-coat window, leading to higher cost for surface pre-treatment and extended down times. Innovative polyamide technology presented here offers significantly increased performance to negate this issue.
12. Available worldwide, but locally milled, talc for heavy duty anti-corrosion primers
Juergen Spehn, Omya International AG, Switzerland
Many multinational paint producers face the same problem, viz. they are forced to adapt formulations to use local raw materials since transporting components too costly, especially large quantities of low-priced products like extenders. To solve this quandary, MONDO MINERALS is now able to provide high quality talc which is milled to the same specification in different locations all over the world. The production of very similar PLUSTALC grades is possible due to the cost-efficient shipment of rocks from very similar raw material sources to the place of use. To prove its suitability in anti-corrosion paints, PLUSTALC C325 was compared to three talc grades that are already known to be used successfully in both water-borne and solvent-borne two pack epoxy primers.
13. Exopolysaccharides (EPS) as anti-corrosive additives for coatings
Dr Jurgen Scheerder, Rik Breur, Ted Slaghek, Ineke van Geel, Wessel Holtman, Marco Vennik and Gabriele Ferrari, DSM NeoResins, The Netherlands
The use of heavy metals and heavy metal based anti-corrosive compounds in organic coatings has been known for decades. However, environmental reasons and health concerns have restricted and even banned the use of these compounds. Exopolysaccharides (EPS) are large sugar molecules (up to 50,000 sugar units) produced by a variety of microorganisms that exhibit anti-corrosive properties. In this contribution we report the use of EPS as anti-corrosive additives in combination with aqueous styrene-acrylic primers for anti-corrosive applications. The effect of the type and amount of EPS on the anti-corrosive properties will be discussed. The distribution of EPS in the coating is studied by Confocal Laser Scanning Microscopy and related to the anti-corrosive properties. Finally, a working mechanism will be proposed. The results indicate that EPS can improve the anti-corrosive performance of waterborne primers.
14. Outstanding metal protection in a nutshell
Dr Jean-Luc Dallons, Cardolite Corporation, Belgium
Synthesis of a unique type of epoxy curing agent known as a phenalkamine. While providing outstanding protection, tolerance to poorly prepared surfaces and low-VOC content, phenalkamines cure epoxy resins very fast and allow coatings to cure at very low temperatures. Phenalkamine-based epoxy coatings are used successfully in the shipbuilding, metallic construction and commercial vehicle manufacturing industries.
15. Siloxanes for concrete protection
Karl-Heinz Kaesler, Momentive Performance Materials, Germany
Concrete is a universal usable and used construction material. Although well known for it s long-term durability it requires protection. Humidity and chloride ions not only attack the concrete but also may lead to corrosion of the rebar steel. The paper will show and demonstrate how siloxanes repel water and humidity and stop chloride ion penetration. The life time of concrete is prolonged by treatment with siloxanes, corrosion of rebar steel will be suppressed.
16. New chemistry improves surface performance
Steven R. Block, Peter Hupfield, Eiji Kitaura, Masayuki Hayashi, Yasuo Itami, Tetsuya Masutani and Katsuhiko Imoto, Dow Corning Corp., USA
Recent developments in the chemistry of silicone and fluorine materials for exterior coating applications present exciting opportunities resulting from their synergistic effects The introduction of silicone cure fluorine resin technology for coating applications can significantly increase corrosion resistance of the underlying substrate. Flexibility, anti stain, low-dirt pick up, chemical resistance and anti-graffiti properties are other key improvements achieved with this new technology. These silicone cure fluoro polymer resins can be cured quickly at room temperature, providing significant cost savings and process application flexibility to the coating applicator. These functions must be achieved while also meeting the demands of environmentally friendly delivery systems, such as high-solids content and solvent systems which comply with strict environmental regulations.
17. New driving forces for intumescent coatings
Dr Claudio Pagella, ProCoat, Italy; R. Epifani, IRIS Vernici and G. Baldi, Politecnico di Torino
The protection of steel structures from fire by means of intumescent coatings is a well-established technology, yet still a growing business. Driven worldwide by the increasing need for safely in building and in Europe strongly influenced by the demanding new standards for fire testing and product classification (ENV 13381, EN 13501) the intumescent coating business is set for changes. While environmental issues and the VOC regulation push for waterborne systems the largest market share is still controlled by solventbornes. The need to prove durability according to meaningful predictive methods is crucial in the competition with alternative technologies (boards, plasters). Applications are widening, ranging from concrete structures to wood (transparent intumescent systems are now available), to the use of intumescent systems to reduce flammability of various materials.
18. Achieving a utopian green coating technology
Philip Hamlin, ProCoat Global Coatings Ltd, UK
Rubber has been well documented for its multiple protective properties used to combat corrosion, wear, impact, vibration, cavitation, electrical and thermal insulation and sound attenuation; characteristics that are well known to industry. This presentation sets out the development path and technical data and test results from engineering an environmental VOC free sprayable rubber coating; the initial goal at first appeared to border on organic transmodification or alchemy, yet successfully culminated in a 100 per cent binded system utilising 50 per cent cryogenically processed rubber crump of <200 μm from recycled tyres delivering an adhesion factor to metal of 6.0 MPa after 4 years atmospheric corrosion testing. Achieving this successful green coating technology and to comply with both current and future legislative and environmentally acceptable trends required an alternative development methodology focusing on life cycle analysis of materials, process and finished product. This approach required a balance against the compromise of delivering a credible cost effective and operationally acceptable system for contractors, buyers, specifiers, designers and engineers.
19. Galvanic corrosion protection of concrete rebar by metallization and paint coating
Solveig Hölzinger and Marc Arav, EMTS Quorum, France
Maintenance of civil and construction works in concrete is becoming a need all over Europe. Till now, it was mainly solved by heavy techniques. Today, it can be done by a single application of metallization thickness 250 μ of 8,515 covered by tie coat and a top coat. This technique well known in North America is rarely used elsewhere. To evaluate it, EMTS QUORUM did first, as state of the art in the USA and Canada, completed by an experimental program done at ISITV laboratory.
20. The use of optically active additives (OAAs) in the protection and preservation of structures
Howard Jess, Luminous Technologies, UK
The purpose of an OAA is to make a coating react to ultra violet light. This effect enables quick, non-invasive inspection of very large coated areas during the application process allowing the inspector to identify and concentrate on defective areas, thus reducing inspection time while assuring the probability of good application and coverage. It works by highlighting holidays and pin-holes, areas of over and under application as well as giving the opportunity for defect detection and identification of early coating deterioration through life. Improved first time coating quality improves coating performance.
21. No paper available22. New applications for coatings containing glass flakes
David Mason, NGF Europe Ltd, UK
The paper will present two recent developments illustrating how coatings containing glass flake are used in new applications based on improved protection of both the substrate and the environment. Traditionally Glass Flake coatings have been used in high performance for aggressive environments, e.g. C5 and C5M The protection of road and rail bridges in these environments has traditionally been achieved with low solids multi-coat MIO systems offering services lives of only 7-15 years. The paper uses independent laboratory (CAPCIS, Manchester UK) results to compare the performance of Glass Flake and MIO pigmented systems in terms of:
Electrical impedance spectroscopy.
Reverse bend impact tests.
Actual coating systems will then be compared to highlight costs savings of up to 30 per cent in applied cost that can be achieved using appropriate glass flake systems.
Once applied high solids low-VOC glass flake coatings offer significantly longer services lives to first maintenance, systems are available offering service lives to major maintenance of 25 years These offer significant savings in the overall coat of corrosion protection over the life of the structure.
In a separate development glass flake coating has been successfully marketed as a biocide-free antifouling coating offering significant environmental benefit over traditional TBT systems, whilst improving the long-term protection of the substrate.
23. Phosphorous rich polymers and mixed intumescent polymeric salts
David Charles Aslin, Prometheus Developments Ltd
The paper will discuss phosphorus rich polymers (PRP) and the derivative technology, Mixed intumescent polymeric salts (MIPS). These provide a system of fire protection and enhancing the reaction to fire behaviour of flammable substrates and materials.
The products involve a novel chemistry that integrates the functional components of conventional intumescents at the molecular scale to produce non-flammable and intumescent polymeric materials that activate at low temperatures and produce negligible smoke.
PRP liquid oligomeric materials are used to produce fire protective paints, varnishes, elastomers, foams and composites.
MIPS is a powder, which is used as a halogen free flame retardant additive for a wide range of polymers. The progress of the commercialisation and IPR protection of the system will be discussed.
24. Disputes in on-shore coatings projects – where they arise and how to avoid them
Miles Robinson and Andrew Briggs, Mayer, Brown, Rowe & Maw LLP, UK
Disputes cost businesses both money and time. They often cannot be avoided but by taking some practical steps before, during and after a coating project, their scope and potential damage to your business can be reduced. This paper considers the various relationships and issues that arise in at typical on-shore coatings project and which can lead to disputes arising. It also provides some practical advice on how best to manage these areas to avoid disputes arising – or at least to reduce their impact on your business.
25. Coatings and risk assessment: health & product safety issues
Philippe Legros, Valérie Winne and Greet Cocquyt, Arcelor/OCAS, Belgium
Safety on the workplace and the health of employees are top priorities for any employer product and processes have to meet strict requirements to ensure that they are not dangerous. Concerning coatings OCAS has developed methods in order to lower the environmental impact and to assess hazards and risks at the earliest stage of each development of new product with an associated process. As example air samplings are performed directly on line during application and curing of new coatings: recently a lot of attention was given to formaldehyde and isocyanates. OCAS has also vast experience in welding fumes analyses using the pyrolysis technique and the characterisation of residual volaties from coated steels.
26. Liquid applied coatings for high temperature corrosive environments
Michael MeLampy and Peter Bock, Hi-Temp Coatings Technology, USA
This presentation will present the use of liquid applied coatings in providing solutions to difficult temperature related corrosion prevention issues. A historical review of technologies through new developments in modern technology products will be discussed. Issues related to corrosion under insulation will also be discussed. The presenter will also provide a prediction in future technologies that may expand functional properties of spray applied products beyond traditional corrosion prevention and aesthetic properties.
27. A new generation high temperature corrosion resistant coating
Dr Adrian Andrews, International Paint, UK
Corrosion under Insulation is a major problem in the petro-chemical and chemical industries where the corrosion rates carbon steel can be significant if operating at high temperature and subject to temperature cycling, particularly when thermally insulated. The protection of these assets thus provides some of the most demanding environments faced by coatings. This paper provides an outline of the development of “cold spray aluminium” coatings technology in comparison to traditional high-temperature coatings systems. The performance (laboratory and field) of the new generation high-temperature corrosion resistant coating together with test method development is discussed.
For further information about this conference and others please visit the PRA web site: www.pra-world.com/conferences/#conferences