Non-halogenated flame retardants for wood coatings
The prospective applications of wood in the furniture industries and building sector are constrained owing to its inherently flammable nature. The application of coatings with flame retardants (FRs) onto the wood substrate is a well-recommended approach to mitigate the risk of fire. Non-halogenated FRs, on the other hand, have gained popularity over halogenated FRs, as halogenated FRs are under regulatory scrutiny due to their carcinogenicity and bio-accumulation issues despite offering excellent FR performance.
Design strategies of reactive and non-halogenated FRs
Furthermore, given the green chemistry principles, it is also recommended to use solvent-free or environmentally benign solvents to make such coatings. The ultraviolet (UV)-assisted curing process is advantageous as it can in practice avoid the use of solvents. A few relevant pieces of literature were found in the bibliographic search databases from January 2015 to December 2022 on UV-curable, non-halogenated FRs for wood coating applications. The current review focuses on the design strategies of reactive and non-halogenated FRs with UV-curable functionalities adapted in recent years, and their applications in various UV-curing polymeric systems such as epoxy acrylate, polyurethane acrylate, thiol-ene systems, and oligomeric systems obtained from bio-based oils. The significant findings of several research groups, the major insights gained and perspectives are covered.
The review has been published in Progress in Organic Coatings, Volume 179, June 2023.