Review on <i>lignin</i> -derived syringaldehyde-based polymers and its applications

In recent years synthesis of novel bio-based aromatic polymer derived from lignin has been gaining the most attention because of its various applications and sustainability approach. Specifically, much interest has been given in creating bio-based polymers using monomers produced from lignin. Lignin is a naturally occurring phenol with a diversity of chemical derivatives that can be broken down into small phenolic compounds. Syringaldehyde is a natural organic derived monomer that belongs to the class of phenolic aldehydes, for example, vanillin, syringaldehyde, ferulic acid, or guaiacol. This review focused on lignin-derived syringaldehyde (3,5-dimethoxy-4-hydroxybenzaldehyde), which is an aromatic aldehyde derived from lignin. There is an increasing demand on sustainability development from various materials that can be recycled, biodegraded, or composted at the end of their useful lives as it is a sustainable polymer. These materials are made using mixtures of waste, recycled, and renewable carbon resources.