In-situ synthesis of organic-inorganic coatings via a photolatent base catalyzed Michael-addition reaction

- Photolatent amines producing the strong base DBN are used as photocatalyst.
- Michael-addition reaction and sol-gel processs occurred simultaneously.
- A general enhancement of scratch resistance was observed for the hybrid coatings.
- A more pronounced by decreasing the dimension of the inorganic domains.

Photolatent DBN derivatives were shown to be suitable catalysts for the in-situ preparation of novel organic-inorganic hybrid coatings. The formulations are based on organic resins crosslinked by a Michael reaction between acetoacetate modified oligomers and acrylic components, and an inorganic precursor undergoing a base-catalyzed sol-gel reaction. The size of the inorganic nanoparticles can be controlled by the addition of suitable coupling agents, thus allowing the design of hybrid coatings with optimized mechanical properties such as scratch resistance.