Preparation and characterization of wood coatings fabricated from 3D interpenetrating networks of hydroxylated rosin-CO2-polyurethane and benzoxazine.

Rosin polyether polyol was synthesized through the hydroxylation of rosin and epoxy. This polyol was then used to modify CO 2 -polyols for the synthesis of rosin-CO 2 -polyurethane (RPU) as a wood coating. Simultaneously, a rosin-based benzoxazine (SBZ) was prepared using sesamol, paraformaldehyde, and dehydroabietylamine, and 3D interpenetrating network system, RPU/SBZ, was formed. The two coatings were further examined. Research has demonstrated that both RPU and the RPU/SBZ 3D interpenetrating network system exhibit excellent mechanical properties, with the latter outperforming the former. The hydrophobic angle of the RPU/SBZ coating measures 119° and remains unchanged over a short period, while the initial water contact angle of the RPU coating is 85° and decreases by 2° shortly after application. The RPU/SBZ composite system coating demonstrates superior chemical resistance, gloss, and adhesion to wood compared to the RPU coating. Additionally, RPU- and RPU/SBZ-based composite system coatings exhibit exceptional flame retardancy as wood coatings. These findings hold significant implications for the development of high-value products in the coating industry. [Display omitted] • The synthesis of green sustainable rosin-CO 2 -based polyurethane has the characteristics of good mechanical properties. • Synthesis of natural based rosin-based benzoxazines. • RPU and SBZ interpenetrating system has good hydrophobicity, flame retardancy, thermal stability, chemical resistance. [ABSTRACT FROM AUTHOR]