Summary
Coating materials for use in exterior applications are generally PVC- or epoxy resin/polyurethane-based, and contain heavy metal-bearing pigments and additives. These products are typically used as protective coatings for overhead line transmission towers, transformer substations and transformers.
The objective of this project was the development of the most environment-friendly coating materials possible:
- of water-based composition,
- with a low organic solvent content,
- containing no synthetic bonding agents.
These materials would be required to meet product specifications for comparable coatings of conventional composition, in terms of processing, corrosion protection and durability, and would need to be suitable for application in a thick-film system.
Results:
- The coatings developed, which are based upon natural and sustainable raw materials, have been given the name “Ökopol”.
- “Ökopol” is based upon a ricin oil/demara resin bonding agent, a natural resin, bentonite and dearomatised benzene.
- Laboratory trials and short-time tests, such as salt spray testing or testing in a sulphur dioxide atmosphere, have produced positive results.
- In tests conducted in compost heaps and under operational conditions, “Ökopol” has shown substantially inferior durability in comparison to either conventional solvent-based alkyd resin/acrylic resin coatings or water dilutable acrylate-/styrol-butyl acrylate-copolymer dispersion coatings.
