Waterborne polyurethane wood coatings based on rapeseed fatty acid methyl esters

Trends in wood coatings are driven to waterborne systems and to renewable resources. Vegetable oils are well known for wood coatings, e.g. alkyds or polyurethane dispersions. In this context fatty acid methyl ester (biodiesel) turns out to be an alternative to technical fatty acids and vegetable oils. High contents on hydrophobic oil based monomers require a sufficient understanding of the dispersion stability. This study shows the influence of hydrophobic monomers, ionic centers, degree of neutralization, and stirring procedure to the particle size distribution and dispersion stability. Furthermore, the impact of these parameters to the resulting coating film properties was investigated.