Polyurethane (PU) coatings have a wide demand in industry and are used for the protection of metal, concrete and wood structures. However, PU coatings face challenges in regard to circular economy concepts. Although waterborne solvent formulation techniques as well as naturally derived monomers are compatible with a circular economy, PU coatings possess a strong barrier. In this study, a series of PU coatings were prepared using water as the main solvent, and the polyol and chain extender monomers used were prepared from natural resources. The synthesized PU coating showed UV resistance, fire retardancy and corrosion protection. The exposed PU coating was collected and used with Portland cement.
The corrosion process that causes metal degradation is natural. The metal and its structure corrode with time. The corrosion rate is usually faster in specific corrosive environments. It is common practice to use an organic coating to mitigate the corrosion process. The coating creates a barrier through which the electrolyte must pass, and thus, the corrosion process is delayed [1-3].
Organic coatings are heavily used on gas and oil pipeline external surfaces for corrosion mitigation. Many pipelines are exposed to the open atmosphere for many years during their service life. The external coating of pipelines degrades under UV sunlight and creates a window for corrosion initiation. The degradation rate is usually faster for aged coatings. This ultimately shortens the lifetime of the pipelines. Therefore, coatings possessing both UV shielding and corrosion resistance are gaining much attention in the petroleum industry [4-6].
These pipelines usually serve a large area and can be surrounded by various environments. Fire incidents are also common. If a coating possesses a fire retardant, fire incidents can be delayed; ultimately, this can save human lives as well as many resources. Thus, coatings with fire retardant properties have become important in industry [6].
