An exploration of the Knoevenagel condensation to create ambient curable coating materials based on acetoacetylated castor oil.

Graphical abstract Highlights • An ambient temperature curable coating based on the Knoevenagel condensation was developed. • The coatings had a high gloss, a high transparency. • Different aromatic dicarboxaldehyde cross-linkers can be used to prepare films. • Characterized the mechanical and thermal properties of these films. Abstract Using a Knoevenagel condensation cross-linking technique, we developed new ambient curable coatings based on acetoacetylated castor oil. The acetoacetylated castor oil was synthesized via the reaction of castor oil with t -butyl acetoacetate, and the films were cured at ambient temperatures (25°C) using aromatic dicarboxaldehydes as crosslinkers. In this article, we optimized the curing conditions of the coating and found that a ratio of acetoacetylated castor oil to dicarboxaldehyde groups of 1:0.75 and a catalyst loading of 7.5 wt % provided an appropriate curing time and the coating with the best performance. Moreover, we prepared films with different aromatic dicarboxaldehyde cross-linkers and characterized the mechanical and thermal properties of these films. [ABSTRACT FROM AUTHOR]