Preparation and characterization of high-solid polyurethane coating systems based on vegetable oil derived polyols

A series of bio-based polyols with high functionality and low viscosity were synthesized from 5 different vegetable oils (refined or crude). Their chemical structures and the distribution of oligomers in these polyols (known as Liprol (TM)) were characterized. Liprol structures varied due to the fatty acid profile of the starting oils and their overall degree of unsaturation, along with the extent of oligomerization during their formation. These polyols were then used as starting materials for the production of high-solid content polyurethane (PU) coatings, by reacting them with commercial petrochemical derived diisocyanate and other additives. All of the PU coatings obtained had a bio-based content of around 60% and showed good thermo-mechanical and mechanical properties. NuLin (R) flax PU, made from oil with the highest linolenic acid content, had the highest glass transition temperature, high contact angle with water, good abrasion resistance and Shore hardness, low degree of solvent swelling and formed highly cross-linked networks. (c) 2013 Elsevier B.V. All rights reserved.