Waterborne & High Solids Coatings – “Reducing Environmental Impact”

Hotel Bloom!, Brussels, Belgium
11 – 12 March, 2008

PROGRAMME

09.30 – 12.30: Tuesday, 11 March

Session 1: Introduction & Background Research

Moderator: David Sykes, PRA

1. Global Market and Technology Trends

Jonathan Bourne

PRA, UK

Waterborne and High Solids Coatings are of particular interest due to the market substitution shifts and the growth opportunities provided in otherwise maturing western markets. However, it is important to recognise the enduring drivers of change in the global coatings market and to understand what new factors are emerging that will affect developments over the next 5 – 10 years. This opening presentation will set the scene for the conference and provide some context to the desire for sustainable development in chemicals and coatings.

2. Product Stewardship: The Use of Solvents in Paintings and Coatings Applications

John Greenhough

Shell Chemicals, UK

The paper will describe the role of ESIG (European Solvents Industry Group) in promoting product stewardship throughout the solvents industry supply chain. ESIG defines product stewardship as the "responsible and ethical management of the health, afety and environmental aspects of a product throughout its total life cycle". The ESIG Product Stewardship program forms part of the wider chemical industry's Responsible Care initiative and cultivates best practice in solvent usage, health, safety and environmental protection. ESIG works closely with the users of solvents to support The Solvents Emissions Directive (SED) and Decorative Paints Directive (DPD). The Solvents Emissions Directive defines VOCs, but does not provide a test method to support this. However, ESIG has developed an on-line vapour pressure tool to help formulators classify complex hydrocarbon solvents. The paper will cover the use of solvents in various industry sectors, including automobile coatings, coatings for metal protection on bridges and pipelines, the consumer DIY market and industrial and professional paint applications.

3. Watching Paint Dry

Dr Anders Larsson

YKI Institute for Surface Chemistry, Sweden

We will in this talk discuss a few of the available techniques to study film formation or sometimes the process more literally known as "Watching paint dry". We will make a short review of the theoretical status of film formation particularly latex film formation and then show examples how that can be followed "live". We will discuss how techniques such as the Horus Film Formation analyser, confocal Raman microscopy, weight loss measurements, QCM-D and electromagnetic labels can shed ight on film drying.

4. The Use of Waterborne Epoxies for Modification of Textile Reinforced Concrete

Allessandra Keil*, Moshe Puterman & Michael Raupach

Institute of Building Materials Research of Aachen University, Germany

Textile reinforced concrete (TRC) is a new composite material, in which textiles from carbon or alkali-resistant glass fibres are used as reinforcement. One advantage of TRC is that it does not require alkaline protection against corrosion resulting in the possibility of low concrete covers and thin elements. An extensive research project SFB 532 at Aachen University financed by the German Research Foundation (DFG) comprises the investigation of this innovative composite material. Waterborne epoxies are used for reinforcement impregnation and concrete modification in order to improve the load bearing capacity as well as the durability of TRC. In this paper the effect of the epoxy addition on the properties of TRC like mechanical properties, bond behaviour and durability will be described.

5. In Silico Weathering of a Coating

Dr Jan Van der Bulcke*, Joris Van Acker & Marc Stevens

University of Ghent, Belgium

Controlled exposure is one of the key factors for putting coating systems to the test. With that in view artificial ageing is widely used to collect information on the performance of a coating system, monitoring the change of parameters such as gloss, colour, adhesion, surface roughness, etc. With the fast evolution of computing power and the increased and detailed knowledge on degradation phenomena, in silico weathering of a coating comes within reach. This offers the possibility to predict performance starting from input data from coating and substrate. Obviously this virtual ageing is a simplified version from the standard lab test, yet it can become a powerful tool for early screening of coating systems.

13.45 – 17.15, Tuesday 11 March

Session 2: New Technology for Meeting EU VOC Regulations

Moderator: Alex Lubnin, Lubrizol

6. New Waterborne Alkyds and PU-Alkyds for Decorative and Joinery Applications

Gerbrand Daamen* and Frank Bergman

DSM NeoResins+, The Netherlands

New developments in composition and the production processes are leading to new waterborne resins. These new alkyd resins and water borne PU-alkyd resins do offer better properties. The combination of a very low VOC content and the good application properties makes them very interesting to the decorative paint market and to the joinery industry. High gloss, improved blocking resistance and outdoor durability are key characteristics achieve by applying these new concepts.

7. A New Performance Additive in High Solids Wood Coating Formulations for Furniture

Paul Swan* & Ralf Taube

Eastman Co, UK

The implementation of EU regulations with respect to reducing the emission of volatile organic compounds (VOCs) from wood coating systems has resulted in continued development of compliant technologies such as UV cure and waterborne. In contrast to the automotive and general industrial industry segments, the high solids approach to industrial wood coatings had been largely overlooked. However, for certain applications high solids solvent borne coating systems can offer excellent attributes long valued by the coatings applicator. New performance additive Solus 2100 is an example of one of Eastman's coatings additives which can provide performance enhancements such as improved flow & levelling, dry to touch time, polishability whilst maintaining excellent non-yellowing characteristics with minimal effect on the level of volatile organic content in the coatings formulations.

8. High Solids Silicone-Alkyd Copolymers for Durable Exterior Coatings

Dr Thomas Easton* & Stuart Poultney

Dow Corning Ltd, UK

The move to high solids solvent-borne paints and coatings involves far more than simply reducing the solvent content during preparation of the binder systems. In the case of alkyd resins lowering the solvent levels without adjusting any other parameters leads to products with unacceptably high viscosities. Lowering the molecular weight can counter this but at the price of impaired exterior durability. Modification with silicone intermediates is a proven way to raise the resistance of coatings to damage from sunlight and water. In this paper we will describe the use of silicone intermediates designed for the modification of high solids alkyds, allowing paint formulators to comply with European Union VOC limits.

9. Routes to VOC Compliant Alkyd Coatings

Kent Soerensen

Perstorp Specialty Chemicals AB, Sweden

Alkyd resins are by nature based on a large share of renewable raw materials being fatty acids and oils. The main environmental problem with alkyd resins is that they are typically used in diluted form in organic solvents. Many roads to VOC compliant coatings have been suggested such as high solids resins and alkyd emulsions. Both of these application forms have a number of technical challenges such as drying performance. We will present some of our findings to improve the properties of such resins by formulating the alkyd resins in various ways such as:

10. New Waterborne Solutions for Stain Blocking Paints and Primers

Maurille Sécher

Eliokem, France

The European 'Decopaint' VOC Directive 2004/42/CE which came into force at the beginning of 2007 will enter its second phase in January 2010, with some significant reductions in VOC limits for certain product categories. Interior paints and primers for stained surfaces is a typical application where solvent based products still play today a major role (because of their performance advantages). Nevertheless the second phase of the Directive might limit the use of solvent based technologies for interior masonry paints. This paper looks at innovations proposed by Eliokem to produce performant VOC compliant waterborne stain-blocking paints and primers.

11. Formulation Factors Influencing the Open Time of Waterborne Trim Paints

Dr Jaap Akkerman*, Dirk Mestach, Wincent Pilaszek & Robert van Egmond

Nuplex Resins BV, The Netherlands

Legislation on the emission of volatile compounds in the European Union is driving the switch from solvent borne to waterborne trim paints. However, currently, the application properties of waterborne trim paints still need to improved. Especially the open time and wet edge time of the applied paint needs to be improved in order to obtain the same high quality level that was possible with conventional solvent-borne trim paints. In this paper new methods are described that can be used to study the fundamental aspects of the open time of paint films. The influence of binder and co-binder composition and morphology is studied. Also the influence of the pigment type and additive package on the application properties has been investigated. These new insights have led to the development of a new hybrid binder concept that offers significantly improved open time.

Conference Dinner

19.00 Reception
19.30 Dinner

09.00 – 12.30, Wednesday, 12 March 2008

Session 3: Developments in Polymer Technology

Moderator: Dirk Mestach, Nuplex Resins

12. Hollow Polyurethane Dispersions

Dr Alex Lubnin*, Susan Lenhard & Valerie Woodward

Lubrizol Corp, USA

Novel hollow polyurethane dispersions are made by recently developed two-prepolymer method for producing nanostructured PUDs. To achieve hollow morphology, we exploited the dramatic difference in reactivity between aliphatic and aromatic isocyanates. Thus, one prepolymer (core) was prepared with hydrophobic polyol and aromatic isocyanate. A second prepolymer (shell) was made from hydrophilic polyol and aliphatic isocyanate. After mixing the two prepolymers and dispersing the mixture in water, hydrophobic polyol pulled aromatic isocyanate groups to the center of the particle, where their hydrolysis generated CO2 gas, a blowing agent. The gas caused particles to bulge from within thus creating hollow particles. The in-situ generated CO2 is environmentally-friendly replacement for traditional blowing agents and the process is conducted in water.

13. Advances in Waterborne Road Marking Paints

Donald C. Schall

Rohm and Haas Co, USA

The technologies used to formulate road marking paints have changed dramatically. In the early 1990 s, the technology shifted from solvent based toward more environmentally friendly and higher performing waterborne acrylic systems. The binder breakthrough which allowed for the widespread use of waterborne paints was a pH triggered quick set that enabled faster dry even under high humidity and low air flow conditions. Waterborne polymers continue to advance in terms of adhesion to surfaces and retention of reflective beads for night visibility. Recent progress enables application of waterborne pavement marking paints under near freezing temperatures, virtually eliminating the need for solvent based paints. The impact of these advances will be presented and environmental, employee safety, and road safety benefits will be reviewed.

14. Water-based Radiation Curable Polyurethane Dispersions as Performance Coatings for Challenging Applications

Philippe De Groote

Cytec Surface Specialties, Belgium

Radiation curable polyurethane dispersions (called UV-PUD) have benefited over the last years from a continuous growth as high-end and innovative performance materials for several markets. These products combine the advantages of (i) polyurethane chemistry (ii) radiation curing technology and (iii) aqueous colloidal dispersions. Such a combination allows to obtain high-performance environment-friendly coatings on various types of substrates with simple formulation work and almost no viscosity limitations. Modifications of the polyurethane backbone can address challenging requirements of the different market segments: wood, PVC resilient flooring, concrete flooring, paper upgrading, plastics and even outdoor applications.

15. Influence of Surfactants on the Viscosity of Paints Thickened by Associative Polymers

Dr Leif Karlson

Akzo Nobel Functional Chemicals, Sweden

The thickening effect of a hydrophobically modified polymer (HMP) is dependent on intermolecular hydrophobic associations and if the polymer concentration is significantly above the overlap concentration also on chain entanglements. HMP interact with all surface active ingredients in the paint. Especially the interactions with surfactants in the formulation play an important role. Addition of surfactants can either increase or decrease the viscosity of a HM-polymer solution depending on the surfactant concentration and surfactant type. Tinting of the paint normally means a dramatic increase of the surfactant concentration in the formulation which has a large impact on the viscosity. The talk will try to give a general explanation of the mechanisms behind the thickening effects of associative thickeners and how they are influenced by surfactants. The influence on the viscosity is dependent on the type of thickener, type of surfactant and surfactant concentration.

16. New Waterborne Epoxy Coatings Technologies: The Next Level

Francoise Heine*, D. Vandenberghe, K.Van Poppel, M. Rans, P. Claeys-Bouuaert, J. Riviere and A. Frederix

Hexion Specialty Chemicals, Belgium

Water based epoxy binders are ne logical approach to reduce Volatile Organic Compounds in anti-corrosion epoxy primers. Thanks to the development of new binder systems, combined with adequate formulation work, waterborne epoxy technology has now proven to be able to replace solventboren technology without sacrificing final coating performance, especially on the anti-corrosion side. This paper will cover the next level of waterborne products and formulation developments, to show that even more difficult requirements could be achieved by waterborne epoxy paint formulations. More difficult cure conditions (low temperatures) and enhanced properties such as improved chemical resistance, improved flexibility and extremely low VOC conditions will be covered. The developments that will be presented are intended for market segments such as transportation, ACE, aerospace, marine and industrial coatings.

17. New PVDC Aqueous Dispersion for Anti-corrosive Paints (tbc)

Benjamin Ladent

Solvay Research & Technology, Belgium

13.45 – 16.15, Wednesday, 12 March 2008

Session 4: Characterisation and Testing

Moderator: Jonathan Bourne, PRA

18. Air Temperature, Air Humidity & Way of Finishing as Factors Affecting Emissions of Waterborne Lacquers

Dr Daniela Tesarova*, Milan Meloun & Zdenek Jergl

Mendel University, Czech Republic

This contribution investigates the influence of air temperature and relative humidity during the drying, the curing and the storing on the VOCs emission and physical and mechanical properties of the furniture parts finished by waterborne lacquers. Emissions VOC emitted by tested samples were monitored under different conditions. The changing of temperature and air humidity improved their impact on emissions' quantity. The other tested criterion was the influence of way of furniture finishing on the emissions' volume. The results were evaluated quantitatively and qualitatively. Quantitative difference of all emitted organic compound showed the measured values of TVOC. The influence of the air temperature and relative humidity increasing during the storing and the drying of the tested samples coated by waterborne lacquers was confirmed during the measurements of the physical-mechanical properties.

19. Optical Technology to Analyse Film-Formation

Helene Dihang & L. Brunel

Formulaction, France

We present in this work an optical technique to study film formation from any type of coating formulation. Our technology is based on Diffusing-Wave Spectroscopy (DWS), an extension of classical dynamic light scattering to concentrated and opaque media. This new and non invasive technique monitors the scatterers motion inside the formulation as a function of time, on the appropriate substrate. Using a laser source and a video camera as detector, the kinetics of film formation is displayed in real time by a specific software and provides a new vision of the successive steps of the mechanism taking place – evaporation, packing, interdiffusion – for an in-depth characterization of the film formation process and an objective evaluation the product performances.

20. Electrochemical Properties of a Waterborne Protective Coating

Dr Zahra Ranjbar*, Shadi Montazeri & Mojtaba Jalili

Institute for Colourants, Paint and Coatings, Iran

The main purpose of this research is formulating and optimizing a new anti-corrosive paint which is an environmentally friendly product. Waterborne Epoxy based coatings were prepared by the reaction of epoxy resins with an amine. The formulation and optimization procedure is carried out on the base of experimental design by the method of mixture in which the important paint properties are modelled by using a special cubic model. The corrosion behaviour of these coatings were investigated by the use of electrochemical impedance spectropscopy (EIS) during a period 35 days exposure to a solution of 5 wt% NaCl in distilled water. Coatings parameters such as the pore resistance and the coating's capacitance measured by ac impedance technique showed three distinct stages of mechanistic corrosion behaviour during the said exposure time.

21. The Art of Reliable Hardness Measurements on High Solids Auto-oxidisable Coatings

Dr Bart Reuvers

DSM NeoResins+, The Netherlands

The pendulum hardness tester is probably the most widely used device to quantify the hardness of coatings. But what about its reliability? In order to validate the outcome of the pendulum tester, the pendulum hardness of coating films has been compared with the hardness achieved with the Dynamic Mechanical Analyses (DMA) Technique, a scientifically founded method to quantify hardness. From the comparative study it turned out that the pendulum hardness tester gives a good impression of the actual hardness if the glass transition temperature of the coating is above room temperature. If not, which is commonly the case for high solid autoxidisable coatings, the pendulum tester turns out to give seriously misleading results. An explanation will be given.