Varnish Alternative Derived from Glycerin

Filed in archive Energy, Environment and Ecology on April 9, 2009

© Elsie esq.

German researchers have developed a varnish alternative in which the majority of petrochemical components have been substituted by vegetable oils and sugars. It has identical properties to the conventional varnishes used today and is hard-wearing, scratch-proof and resistant to chemical attack.

The new varnish is based on the chemical compound 1,3-propandiol, which is derived from glycerin. Glycerin in turn is the basic substance found in all vegetable oils, and is readily available as a byproduct of manufacturing processes for fatty acids and biodiesel, for example. In the laboratory synthesis, the researchers transform 1,3-propandiol into polyurethane, which serves as a binder in hard, transparent, scratch-resistant varnishes. "The aim is to use the relatively cheap 1,3-propandiol as a substitute for one of the more expensive petrochemical synthesis components, without altering the coating properties of the varnish," explains Dr. Guido Hora, department head at the Fraunhofer WKI.

It performs equally well as petroleum-derive varnishes with the added advantage of containing no N-methyl-2-pyrrolidon (NMP), which is known to have a toxic effect on the growing embryo and is classed throughout the EU as a hazardous chemical requiring a warning symbol on all products containing a concentration higher than five percent.