Consumables
Dow Coating Materials Improves Environmental Performance for “Any colour you like, so long as it is Green!” coatings
Friday 26. June 2009 - Sherika Anandev, a distinguished scientist with The Dow Chemical Company (NYSE:DOW) in New Germany, South Africa, recently presented a paper at the Oil and Colour Chemists Association (OCCA) symposium held in Westville, Durban. OCCA, which is supported by technical specialists in surface coatings industries throughout the world, hosts a number of technical presentations on new technologies each year, and this was attended by representatives from over 40 paint companies and raw material suppliers in South Africa.
In keeping with the theme of this event Any colour you like, so long as it is green, Sherikas presentation discussed the “Durability of Waterborne Acrylic Polymers as a Driver for Improved Environmental Performance.”
During the 1980s, waterborne acrylic resin technology gained considerable acceptance for coatings that have to offer both protective and decorative performance, even on difficult substrates. But advances in polymer design and formulation have now, in many cases, improved performance levels of waterborne maintenance coatings beyond the capabilities of solvent-borne coatings. In addition, because low odour waterborne coatings comply with increasingly stringent regulations on volatile organic compounds, their acceptance throughout the world is being accelerated.
The acrylic polymer and water component in waterborne paints makes them easier to manufacture and easier to clean. The achievement of performance levels for waterborne maintenance coatings depends on a thorough understanding of the formulating variables. Formulation ingredients, like pigments, dispersants, coalescing solvents and thickeners, and stressing corrosion resistance, significantly influence either the short or long term performance of the protective film.
So to measure the long term performance of the coatings, painting projects with waterborne acrylic coatings are carried out at different Dow Coating Materials locations and the applications are extended over a variety of surfaces and subjected to varying temperatures and humidity levels. This data gives scientists a better insight into the mechanisms that govern paint performance, which in turn facilitate the development of formulations tailored to specific exposure conditions and the creation of new paint components. Dow Coating Materials is then able to provide customers with useful assistance in their efforts to create viable paint formulations.
These in-depth studies, focus on the exterior durability of both alkyd and acrylic based coating systems for different applications and range from a period of 14 months to nine years. Waterborne paints often display superior resistance to yellowing, cracking and peeling, dirt and mould growth, as well as chalking. These results show that in a general sense, acrylic polymers are far more durable than alkyd polymers. This exceptional durability translates to less frequent re-painting, which results in reduced raw material and energy usage, as well as substantial cost benefits.
Over the last few years, Dow Coating Materials has continuously introduced technologically innovative and environmentally advanced acrylic polymers as alternatives to conventional alkyd polymers. At the OCCA seminar, Sherika highlighted the following products as examples of the Dow Coating Materials water borne portfolio:
FastrackTM Technology for water based road marking paint. This binder has superior performance and can contribute to reducing carbon emissions compared to solvent borne road marking paints.
HydrotechTM Technology for high gloss paints. This binder has improved durability and can contribute to improving the environmental impact over a 20 year life cycle.
RopaqueTM Polymer for titanium dioxide replacement. This chemistry can help to lower the embodied carbon in a paint, while reducing formulation costs.
The company has also investigated the “carbon footprint” as well as “life cycle analysis” type data of solvent and water-based coatings. Amongst the criteria analysed was energy use, gas emissions, raw material use (non renewable and recyclable), cost and waste, as well as health and safety analysis. These results indicate that water based acrylic paints can help lead to improvements towards sustainability and a lower harmful impact on the environment.
Sherika concluded the presentation by emphasising that the enhanced performance and durability of water based acrylic paints can enable significant steps in lowering overall environmental impact.